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Tephrochronology of the astronomically tuned KC01B deep-sea core, Ionian Sea: insights into the explosive activity of the Central Mediterranean Sea during the last 200ka
... However, while the most powerful Late Pleistocene (e.g., post-NYT and partially post-CI) eruptions at CF have been the subject of extensive investigations (e.g., Di Vito et al., 1999;Smith et al., 2011), only recently the studies on the pre-CI eruptive history (Paterne et al., 1988;Di Vito et al., 2008;Insinga et al., 2014;Monaco et al., 2022a;Tomlinson et al., 2022 and references therein;Vineberg et al., 2023) have been carried out. Specifically, some of the most widespread Middle-Late Pleistocene Mediterranean tephra layers were recently linked to a pre-CI activity that occurred between ~60 ka and 50 ka (e.g., Vineberg et al., 2023) and between ~200 ka and 90 ka (e.g., Wulf et al., 2012;Petrosino et al., 2016;Giaccio et al., 2017b;Monaco et al., 2022aMonaco et al., , 2022b, extending back in time the eruptive history of CF. ...
... Major element glass compositional data were provided by different authors (e. g., Keller et al., 1978;Sulpizio et al., 2010;Giaccio et al., 2012;Wulf et al., 2012;Donato et al., 2016) as a first step to ascribe them to a generic 'Campanian source'. In addition, some samples were also analysed for trace elements and Sr and Nd isotope compositions, which all highlighted the affinity with CF, therefore the most probable source for these tephra layers (e.g., Insinga et al., 2014;Giaccio et al., 2012Giaccio et al., , 2017bWulf et al., 2012Wulf et al., , 2018Petrosino et al., 2019). ...
... With this regard, we collected and summarised all the available literature information on CF tephra layers related, or potentially related, to the CF volcanic activity spanning the ~110-90 ka interval and around 160 ka, recognized from proximal to distal and ultra-distal settings. Specifically, some distal sedimentary archives have been pivotal for tephrochronological purposes, i.e., the Fucino (e.g, Giaccio et al., 2017b) and Sulmona Basins (e.g., Regattieri et al., 2017), the Adriatic (e. g., Bourne et al., 2015), Tyrrhenian (e.g., Paterne et al., 2008;Petrosino et al., 2016;Sammartini et al., 2019) and Ionian Sea (e.g., Insinga et al., 2014;Vakhrameeva et al., 2021), Lago Grande di Monticchio (e.g., Wulf et al., 2004Wulf et al., , 2008Wulf et al., , 2006Wulf et al., , 2012 and Lake Ohrid (e.g., Caron et al., 2010;Leicher et al., 2016), as they are in favourable downwind positions and are valuable records for studying the past explosive activity of the Campanian area. In particular, several sediment cores have been drilled at Lago Grande di Monticchio (southern Italy), due to its strategic position, to reconstruct the eruption history of the volcanoes located in central and southern Italy (e.g., Wulf et al., 2004Wulf et al., , 2008Wulf et al., , 2012. ...
The Campi Flegrei (CF) caldera, in southern Italy, is the source of some of the most powerful Late Pleistocene eruptions of the European sub-continent (e.g., Campanian Ignimbrite, Neapolitan Yellow Tuff eruptions). Although the CF caldera has been continuously and intensively investigated for decades, relatively little is known regarding its earliest volcanic activity. In this work, integrating existing and new tephrostratigraphic data, we provide a comprehensive and updated framework for the CF volcanic activity which has occurred at ~160 ka and between ~110 ka and ~90 ka. The new tephrostratigraphic, geochemical (EMPA + LA-ICP-MS), chronological (40Ar/39Ar dating) and grain-size distribution data relate to CF tephra deposits preserved in mid-proximal (Campanian Plain), distal (Tyrrhenian Sea) and ultra-distal (Lower Danube area) sedimentary archives. Our results allowed us to recognize the presence of at least 13 CF eruptions covering the investigated time frame, with 12 eruptions occurring between 110 and 90 ka. Our high-resolution stratigraphic and chronological investigation also allowed us to recognize that the Triflisco/C-22 tephra, previously considered as a single marker layer, can be actually separated into three different events, sourced from within the CF area in the short time interval of ~93- 90 ka, suggesting a more complex and intense volcanic history than previously thought. Moreover, a Bayesian age-depth model, constrained by previous and new high precision 40Ar/39Ar ages, has led to a reliable estimate of the ages of those undated CF eruptions. Overall, the updated framework on the stratigraphy, chronology, dispersion, and geochemistry of the CF tephra of ~160 ka and between 110 ka and 90 ka consolidates the notion that the Middle-Late Pleistocene activity in theCF area represents a significant stage of its volcanic evolution, characterised by intense and frequent explosive eruptions.
... The total volume of erupted magma has been [19]). (B) Map of the central Mediterranean area; numbered red circles indicate the main distal locations where the MEGT products have been either recognised or hypothesised: 1-PRAD 1-2 bore hole, Adriatic Sea [20]; 2-KET 8218 bore hole, Adriatic Sea [3]; 3-Fucino Basin, Abruzzo, Central Italy [2]; 4-Lago Grande di Monticchio, Basilicata [4,6]; 5-San Gregorio Magno basin, Campania [7,8]; 6-Oscurusciuto [10]; 7, 8, 10, 11-KET 8022, KET 8004, KET 8003, KET 8011 bore holes, Tyrrhenian Sea [3]; 9-ODP Leg 107, Site 650, Tyrrhenian Sea [21]; 12-Stromboli, Aeolian Archipelago [22]; 13,14,, RC9-191, V10-68 bore holes, Ionian Sea [23]; 15-M25/4-11 bore hole, Ionian Sea ( [9] and references therein); 17-ODP Leg 160 Site 964 and KC01B bore holes, Ionian Sea [5,24]. ...
... In his re-evaluation of previous astronomically tuned timescales for cores from Ocean Drilling Program Leg 160 Site 964 and KC01B in the Ionian Sea (circle 17 in Figure 1B), Lourens (2004) [5] found that the tephra I4 could be correlated to both Y-7 of Keller et al. (1978) [23] and C-17 of Paterne et al. (1988) [3]. However, this correlation was questioned by Insinga et al. (2014) [24] using major oxides arguments, leaving open the possibility that I4 could have been generated from a volcanic source located either at Ischia in a time very close to the MEGT or in the Campi Flegrei area. Bourne et al. (2010) [20] investigated tephra layers recovered from core PRAD 1-2 in the central Adriatic Sea (circle 1 in Figure 1B). ...
... In his re-evaluation of previous astronomically tuned timescales for cores from Ocean Drilling Program Leg 160 Site 964 and KC01B in the Ionian Sea (circle 17 in Figure 1B), Lourens (2004) [5] found that the tephra I4 could be correlated to both Y-7 of Keller et al. (1978) [23] and C-17 of Paterne et al. (1988) [3]. However, this correlation was questioned by Insinga et al. (2014) [24] using major oxides arguments, leaving open the possibility that I4 could have been generated from a volcanic source located either at Ischia in a time very close to the MEGT or in the Campi Flegrei area. Bourne et al. (2010) [20] investigated tephra layers recovered from core PRAD 1-2 in the central Adriatic Sea (circle 1 in Figure 1B). ...
The 56 ka Monte Epomeo Green Tuff (MEGT) resulted from the largest volume explosive eruption from Ischia island (south Italy). Its tephra is one of the main stratigraphic markers of the central Mediterranean area. Despite its importance, a detailed characterisation of the petrography and mineral chemistry of MEGT is lacking. To fill this gap, we present detailed petrographic description and electron microprobe mineral chemistry data on samples collected on-land from the MEGT. Juvenile clasts include pumice, scoria, and obsidian fragments with porphyritic/glomeroporphyritic, vitrophyric, and fragmental textures. The porphyritic index is 13–40 vol.%, and phenocryst phases include alkali-feldspar, plagioclase, clinopyroxene, ferrian phlogopite, and titano-magnetite, in order of decreasing abundance; accessory phases include sphene, hydroxy-fluor-apatite, and rare edenite. Plagioclase varies from predominant andesine to subordinate oligoclase, whereas alkali-feldspar is more variable from sanidine to anorthoclase; quasi-pure sanidine commonly occurs as either rim or recrystallisation overgrowth of large phenocrysts due to hydrothermal alteration. Secondary minerals include veins and patches of carbonate minerals, Fe-Mn oxyhydroxides, clay minerals, and zeolites. Clinopyroxene is ferroan diopside (En45–29Fs7–27) and never reaches Na-rich compositions. This feature allows the discrimination of MEGT from aegirine-bearing, distal tephra layers erroneously attributed to MEGT, with implications for the areal distribution of Ischia explosive deposits.
... However, only a few records reach back to the late Middle Pleistocene Calanchi and Dinelli, 2008;Insinga et al., 2014;Munno and Petrosino, 2007;Paterne et al., 2008). For example, the interval between 200 and 400 ka lacks a tephrostratigraphic framework and studies focused on chronological and volcanological aspects (Belkin et al., 2016;Cioni, 1987;Karner and Marra, 1998;Karner et al., 2001;Marra et al., 2016Marra et al., , 2017aPalladino et al., 2010Palladino et al., , 2014Perini et al., 2004). ...
... Several long marine (e.g., KC01B, PRAD1-2; Lourens, 2004;Piva et al., 2008) and terrestrial sedimentary archives from the Mediterranean region, such as Fucino (Giaccio et al., 2015b, Ioannina (Tzedakis et al., 2003), and Tenaghi Phillipon would allow an improvement of the tephrostratigraphy back into the Early and Middle Pleistocene, but tephrostratigraphic studies of most records concentrated on the younger intervals Insinga et al., 2014;Wulf et al., 2018). For the older periods, only the existence of tephra layers was described (Lourens, 2004;Piva et al., 2008), except for first cryptotephra studies on the Tenaghi Philippon peat for the period 235 ka to 460 ka (Vakhrameeva et al., 2018(Vakhrameeva et al., , 2019, which contributed mainly to the Eastern Mediterranean tephrostratigraphy. ...
... LA-ICP-MS trace element analyses of individual glass shards were successfully applied to younger volcanic deposits of the CVZ or the Aeolian Arc (e.g., Albert et al., 2012Albert et al., , 2015Albert et al., , 2017Insinga et al., 2014;Smith et al., 2011;Tomlinson et al., 2012aTomlinson et al., , 2014Tomlinson et al., , 2015, but have rarely been applied for other Italian Middle Pleistocene volcanic deposits (Petrosino et al., 2015). Using datasets of younger deposits has to account for potential changes in the magmatic system of a volcanic district over time (e.g., Roccamonfina; Rouchon et al., 2008). ...
Lake Ohrid, located in the Central Mediterranean region downwind of the Italian volcanoes, has great potential for developing a detailed record of the explosive activity of these volcanoes. Electron microprobe and Laser Ablation Inductively Coupled Plasma Mass Spectrometry geochemical analyses of juvenile glass fragments of previously not analysed tephra layers of the DEEP site sediment record of Lake Ohrid expand the existing tephrostratigraphy for the interval Marine Isotope Stages 1–16. The geochemical signatures of all tephra layers suggest an origin exclusively from the Italian volcanism.
Eight of these tephra layers have potential equivalents in marine and terrestrial archives of the Central Mediterranean region (OH-DP-1966/SC5/A7; OH-DP-1955/CES1/A2; OH-DP-1055/S1; OH-DP-1006/S2; OH-DP-0997/S3, OH-DP-0710/S8/C-51; OH-DP-0766/ODP5/P-13; OH-DP-0505/ODP4). Nine tephra layers, which have not been described so far, help to reconstruct the late volcanic activity of Mount Vulture (OH-DP-2439) and the Paleovulsini (OH-DP-1998), the pre- and post Rio Rava activity of the Roccamonfina volcano (OH-DP-1911/-1812/-1733/-1640/-1527), the early activity of the Aeolian Arc (OH-DP-1513/-1520), and the Bracciano activity of the Monti Sabatini volcanic district (OH-DP-1175). The multi-proxy dataset and chronology of the DEEP site sediments allowed definition of the climatostratigraphic position for all tephra layers and constrain the ages of so far unknown and/or undated tephra layers. The presented data provide a crucial increase of knowledge of the Middle Pleistocene tephrostratigraphy in the Central Mediterranean back to 630 ka and allows new insights of the volcanic activity of Roccamonfina, the Roman Province, the Campanian Volcanic Zone (CVZ), the Aeolian Arc, Pantelleria, and Mount Vulture.
... This is particularly true for the central Mediterranean, a key area for tephrochronology due to the occurrence of active volcanoes during the Quaternary and the availability of long and continuous marine and continental archives (e.g. Keller et al., 1978;Paterne et al., 1988Paterne et al., , 2008Calanchi et al., 1998;Siani et al., 2004;Wulf et al., 2004;Munno and Petrosino, 2007;Sulpizio et al., 2010;Insinga et al., 2014;Matthews et al., 2015;Giaccio et al., 2017). To date, in the marine setting, tephra and cryptotephra have been analyzed in ca. ...
... Correlation of the analyzed tephra with proximal deposits or equivalents from different sites was based on a comparison of the new data with published scanning electron microscopy/energy-dispersive spectrometry (SEM-EDS) and wavelength-dispersice spectroscopy (WDS) data where available. The criteria used to infer the primary origin of the studied deposits are described in Insinga et al. (2014). ...
... This is mostly due to the insufficiency of data available on these proximal deposits in terms of single glass shard chemistry. This paucity reflects the difficulties when comparing different datasets (generally bulk versus single glass analysis) to establish proximal-distal correlations and recognize the eruptive event (Insinga et al., 2014). Moreover, the microlite-rich groundmass and the rare interstitial glass, which are typical features of these Etnean deposits (Coltelli et al., 2000), make their chemical characterization a difficult task even at proximal sites. ...
Five cores from the southern Tyrrhenian and Ionian seas were studied for their tephra and cryptotephra content in the 4.4–2.0 ka time interval. The chronological framework for each core was obtained by accelerator mass spectrometry 14C dating, the occurrence of distinct marker tephra and stratigraphic correlation with adjacent records. Tephrochronology allowed us to correlate the analyzed deposits with tephra markers associated with Somma‐Vesuvius (79 ad), Ischia Island (Cretaio), Mt Etna (FG, FL and FS) and Campi Flegrei (Astroni‐Agnano Monte Spina) events. For the first time in the marine setting, a large single glass data set is provided for the Late Holocene Etnean marker beds including the FS tephra (ca. 4.3 ka). Moreover, unknown deposits from Lipari (ca. 2.2–2.0 ka) and Vulcano (3.6–3.3 ka) are also recognized at more distal sites than previously reported. These results contribute to improve the high‐resolution tephrostratigraphic framework of the central Mediterranean Sea. They also provide new insights into the chemical composition and dispersal pattern of tephras that can be used as inter‐archive tools for regional and ‘local’ stratigraphic correlations and for addressing paleoclimate research.
... Moreover, minor eruptive episodes, mostly effusive, occurred ca. 150 ka at Roccamonfina (Rouchon et al., 2008) and Campania products from uncertain sources, older that 90 ka, are recorded on-land as widespread deeply altered ignimbrite deposits (Rolandi et al., 2003;Belkin et al., 2016). The Campania tephra marker record, on the other hand, is very rich, as testified by the finding of distal tephra layers with a chemical composition typical of Campania products both in lacustrine (Monticchio Lakes: Wulf et al., 2004Wulf et al., , 2012SGM: Munno and Petrosino, 2007;Ascione et al., 2013) and marine (Tyrrhenian Sea: Paterne et al., 1986Paterne et al., , 2008Morabito et al., 2014;Petrosino et al., 2016;Ionian Sea: Keller et al., 1978;Insinga et al., 2014;Adriatic Sea: Siani et al., 2004;Bourne et al., 2010Bourne et al., , 2015 sedimentary sequences. ...
... 109 ka (Iorio et al., 2014), although their terrestrial counterpart remains unknown. The chemical composition of most of the pre-CI Campania marker levels is alkali-trachytic with variable Na 2 O/K 2 O ratio (Paterne et al., 2008;Wulf et al., 2012;Insinga et al., 2014). ...
... The tephra was attributed to a generic pre-CI event from the Campanian Volcanic Zone by Munno and Petrosino (2007) and then dated to~240 ka by Ascione et al. (2013). Its trace element composition ( Figure 7A; Supplementary Information Figs S1, S2A and S3A) closely resembles the patterns of the distal tephra layers found in deep sea sediment core K109B from the Ionian Sea attributed to pre-CI Campania Plain explosive activity (Insinga et al., 2014). These patterns closely match those of bulk rocks and glasses from CI and pre-CI deposits cropping out on land (Pappalardo et al., 1999;Tomlinson et al., 2012 and references therein). ...
Central–southern Italy is one of the most suitable areas in the world for tephrostratigraphic studies, owing to the numerous volcanic sources with explosive activity during the Pleistocene. This work presents a systematic investigation of the chemical (trace elements) and isotopic (Sr and Nd) compositions of the main tephra markers within lacustrine sediments of the San Gregorio Magno Basin (Campania, southern Italy). This study: (i) provides full geochemical (trace elements and isotopes) characterization of eight significant Upper Pleistocene marker layers (X‐6, X‐5, C‐22, MEGT/Y‐7, CI/Y‐5, C‐10, Y‐3, NYT/C2) widely dispersed over the Mediterranean area; (ii) proposes a new tephra marker for Marine Isotope Stage 7, dated to 240 ka; and (iii) refines the correlations of tephra levels belonging to the investigated sequence. This study highlights that in most cases the Nd isotope composition of the glass and Sr isotope composition of the coexisting minerals are more reliable than 87Sr/86Sr of the glass, and hence is more helpful as a further tool for tephrostratigraphic correlations, as recently proposed in the literature. Moreover, this study is a first step towards the construction of a complete geochemical database for future tephra investigations in the Mediterranean area.
... Explosive volcanism in the Aeolian Islands is responsible for the distal dispersal of tephra (volcanic ash, b 2 mm). Distal occurrences of Aeolian Island derived tephra are reported within marine archives from across the central Mediterranean, including the Tyrrhenian (Paterne et al., 1986(Paterne et al., , 1988Di Roberto et al., 2008;Albert et al., 2012), Adriatic (Siani et al., 2004;Matthews et al., 2015) and Ionian (Clift and Blusztajn, 1999;Caron et al., 2012;Insinga et al., 2014) Seas. Furthermore, Aeolian Island tephra are also recorded in terrestrial sequences from Sicily (Morche, 1988;Narcisi, 2002). ...
... The investigated tephra deposits on Salina are associated with the Pollara activity. The sub-Plinian fall deposits of the Lower Pollara succession (26,410-27,630 cal yrs BP; Table 2) have glasses that straddle the (Paterne et al., 1988;Albert et al., 2012;Matthews et al., 2015;Insinga et al., 2014) and lacustrine (Narcisi, 2002) CA/HKCA boundary (Fig. 3a). Glass analysis of the opening scoria fall were not successfully obtained owing to the absence of matrix glass within these particularly crystal rich clasts. ...
... The glasses of samples analysed here all share a KS affinity (Fig. 3a). Geochemically, these glasses do compositionally vary spatially between different localities on the island, and these variations are largely (Paterne et al., 1988;Albert et al., 2012;Matthews et al., 2015;Insinga et al., 2014) and lacustrine (Narcisi, 2002) archives that are considered here for proximal-distal correlations. Error bars represented 2 * standard deviations of replicated analyses of the StHs6/80-G secondary standard glass. ...
Volcanic ash (<2mm) erupted from the Aeolian Islands is reported distally as layers in sedimentary archives from across the central Mediterranean region. Here we present volcanic glass geochemistry of proximal tephra deposits from explosive eruptions on the islands of Vulcano, Lipari, Salina and Stromboli spanning approximately the last 50ka using grain-specific EMPA and LA-ICP-MS. This comprehensive database of volcanic glass compositions (>1000 analyses) provides a basis for proximal-distal and distal-distal tephra correlations. Tephra deposits from the different Aeolian Islands are geochemically diverse; with some individual eruptions showing diagnostic geochemical heterogeneity recognised both stratigraphically and/or spatially. Major element glass analyses reveal that Vulcano (0-21ka) and Stromboli (4-13ka) have erupted potassic (shoshonitic and K-series) tephra with broadly overlapping compositions, but data presented here demonstrates that their eruptive products can be distinguished using either TiO2 contents or their HFSE/Th ratios. Whilst individual volcanic sources often produce successive tephra deposits with near identical major and minor element compositions through time (i.e., Lipari, Vulcano), trace element glass data can help to decipher successive eruptions. Changes in LREE and Th concentrations of volcanic glasses erupted spanning approximately the last 50ka greatly enhance the potential to discriminate successive eruptive units on Lipari. The new proximal glass database has been used to verify new (Ionian Sea; core M25/4-12) and existing distal occurrences of Aeolian Island derived tephra enabling the reassessments of past ash dispersals. Finally, proximal and distal data have been used to establish an integrated proximal-distal eruptive event stratigraphy for the Aeolian Islands.
... Over the last decades, marine tephra studies have allowed to significantly improve the reconstruction of the explosive activity of Mediterranean volcanoes (e.g. Keller et al., 1978;Paterne et al., 1986Paterne et al., , 1988Paterne et al., , 2008Margari et al., 2007;Caron et al., 2010;Insinga et al., 2014;Tomlinson et al., 2015;D'Antonio et al., 2016;Wulf et al., 2018;Giaccio et al., 2019;Friedrichs et al., 2020;Vakhrameeva et al., 2021;Monaco et al., 2022), with important outcomes in terms of recurrence estimates of high-energy events and related potential hazard. In addition, the identification of tephra layers in marine and lacustrine sediments has supplied a significant stratigraphic and chronological support to paleo-climatic, paleooceanographic and archaeological investigations in the Mediterranean basin Caron et al., 2010Caron et al., , 2012Zanchetta et al., 2018;Giaccio et al., 2012Giaccio et al., , 2019. ...
... The widespread findings of tephra layers with peralkaline signature, related to the volcanism of Pantelleria, in both marine and lacustrine successions in the central and eastern Mediterranean area demonstrate the wide dispersion of the deposits generated during the explosive events, which reached distances of up to 1200 km away from their source along a main NE-ward dispersal axis (Wolff and Wright, 1981;Narcisi and Vezzoli, 1999;Margari et al., 2007;Paterne et al., 2008;Caron et al., 2010;Vogel et al., 2010;Tamburrino et al., 2012;Damaschke et al., 2013;Insinga et al., 2014;D'Antonio et al., 2016;Zanchetta et al., 2018). Among the distal deposits, the most widespread marker horizon has been correlated with the GT eruption, which is believed to have generated the Y-6 tephra in marine sequences in the Ionian Sea and Sicily Channel (Keller et al., 1978;Narcisi and Vezzoli, 1999;Tamburrino et al., 2012), in lacustrine records in Greece and Albania (Margari et al., 2007;Vogel et al., 2010) and in the Marsili Basin, southern Tyrrhenian Sea (Tamburrino et al., 2016). ...
... Collected near volcanoes or volcanic islands, more distant tephra deposits thus provide a "history" of nearby explosive eruptions, complementing the knowledge of eruptive history determined from the study of deposits conducted in the proximal domain. Many works have demonstrated the importance of these approaches and their contribution to volcanic hazard forecasting (Watkins et al. 1978;Gehrels et al. 2006;Bertrand et al. 2008;Sulpizio et al. 2008;Insinga et al. 2014). Another use of marine and lacustrine tephra is the correlation of (distal) deposits from very large (Plinian) eruptions and relatively infrequent explosive eruptions (Pyle et al. 2006;Bazin et al. 2019). ...
... While sedimentary archives, whether marine or lacustrine, can be used in many contexts, it is probably in the Mediterranean area that the greatest number of studies is available. A chronology based on major events is now established with good accuracy, from independent sources mixing data from lake sediments (varves) and data from marine sediments (Insinga et al. 2014;Bazin et al. 2019) (Figure 1.29). Tephra layers with a wide distribution are used as a reference for further work. ...
... Collected near volcanoes or volcanic islands, more distant tephra deposits thus provide a "history" of nearby explosive eruptions, complementing the knowledge of eruptive history determined from the study of deposits conducted in the proximal domain. Many works have demonstrated the importance of these approaches and their contribution to volcanic hazard forecasting (Watkins et al. 1978;Gehrels et al. 2006;Bertrand et al. 2008;Sulpizio et al. 2008;Insinga et al. 2014). Another use of marine and lacustrine tephra is the correlation of (distal) deposits from very large (Plinian) eruptions and relatively infrequent explosive eruptions (Pyle et al. 2006;Bazin et al. 2019). ...
... While sedimentary archives, whether marine or lacustrine, can be used in many contexts, it is probably in the Mediterranean area that the greatest number of studies is available. A chronology based on major events is now established with good accuracy, from independent sources mixing data from lake sediments (varves) and data from marine sediments (Insinga et al. 2014;Bazin et al. 2019) (Figure 1.29). Tephra layers with a wide distribution are used as a reference for further work. ...
The complexity of understanding volcanic risk is partly due to the fact that it is the result of different hazards, some of which are directly linked to the eruptive activity, such as, gas, lava flows, pyroclastic flows and ash fallout, and others which are directly or indirectly induced by these hazards, such as, debris avalanches, tsunamis, mudflows or lahars. A wide range of seismic phenomena is associated with volcanic activity. The main sources of seismic signals are: magma transfers; hydrothermal activity; and volcano‐tectonic phenomena. Understanding the hazard associated with volcanic gases means first of all understanding the physico‐chemistry of the outgassing process. Volcanic explosions produce and eject tephra of various sizes and gases. Tephra are classified into three main classes: bombs, lapilli and ash. Lahars are part of a continuum of water‐rich flows, but sediment concentration, particle size distribution and density help distinguish the following two categories: hyperconcentrated flows and debris flows.
... From Lake Ohrid, OH-DP-0617 Vico B with 162 ± 6, OH-DP-0624 CF-V5 Pitigliano Tuff with 163 ± 22 ka are possible equivalent candidates (Leicher et al., 2016). From the Ionian sea, three tephra layers of similar age range are reported: I-13/KC01B (161.9 ka (Insinga et al., 2014)), P-12/KET82-22 (164 ka (Paterne et al., 2008)), and I-14bottom/KC01B (167.2 ka (Insinga et al., 2014)). Possible equivalent tephras from the Fucino Basin (Italy) could be TF-15 (Vico Ignimbrite C with an 40 Ar/ 39 Ar age of a correlated tephra of 153.5 ± 4.6 ka), TF-16 (Vico Ignimbrite B, with 160.6 ± 4.0 ka), and TF-17 stemming from the Campanian Volcanic Zone (Taurano Ignimbrite with 159 ± 1.6 ka) (Giaccio et al., 2019). ...
... From Lake Ohrid, OH-DP-0617 Vico B with 162 ± 6, OH-DP-0624 CF-V5 Pitigliano Tuff with 163 ± 22 ka are possible equivalent candidates (Leicher et al., 2016). From the Ionian sea, three tephra layers of similar age range are reported: I-13/KC01B (161.9 ka (Insinga et al., 2014)), P-12/KET82-22 (164 ka (Paterne et al., 2008)), and I-14bottom/KC01B (167.2 ka (Insinga et al., 2014)). Possible equivalent tephras from the Fucino Basin (Italy) could be TF-15 (Vico Ignimbrite C with an 40 Ar/ 39 Ar age of a correlated tephra of 153.5 ± 4.6 ka), TF-16 (Vico Ignimbrite B, with 160.6 ± 4.0 ka), and TF-17 stemming from the Campanian Volcanic Zone (Taurano Ignimbrite with 159 ± 1.6 ka) (Giaccio et al., 2019). ...
Loess-paleosol sequences (LPS) from the Lower Danube area are valuable terrestrial archives of environmental change in SE Europe during the Pleistocene. A twenty-seven meters thick sequence has been sampled in Central North Bulgaria near the city of Pleven within the Suhia Kladenetz (SK) quarry. The sedimentary sequence consists of seven loess units and six interbedded paleosol complexes covering the last 800 kyrs. The continuous 2 cm resolution sampling depth interval enabled the recovery of several cryptotephras in addition to a ~ 20 cm thick tephra deposit observed in the field within the L2 loess unit. All cryptotephras are clearly identified in laboratory analyses by their strong magnetic signal, particularly well expressed by concentration – dependent anhysteretic susceptibility (χARM), isothermal remanence (IRM), low field magnetic susceptibility (χlf) and in some cases by frequency dependent magnetic susceptibility (Δχ), coercivity of remanence (BCR), and hard isothermal remanence (HIRM2.0–0.3T). Complementary optical and scanning electron microscope analyses of single grains from the tephra deposit and cryptotephra intervals reveal the presence of volcanogenic grains with smooth glassy surfaces and vesicular internal structure; fluidal grains with bulbous surfaces and dense irregular grains. Grain size sensitive magnetic ratios χARM/χlf, ARM/IRM100mT, IRM2T/χlf are not always discriminative, suggesting that (crypto)tephras do not have a single uniform source. Preliminary correlative age models are used to estimate ages for the (crypto)tephras and propose likely associated volcanic eruptions. Finally, strong pedogenic magnetic enhancement of the younger paleosols (S4, S3, S2 and partly S1) contrasts with the smeared and low magnetic signal of the older paleosols (S6 and S5). Moreover, an enhanced content of low-coercivity hematite observed from the upper part of the S5 paleosol upwards to the present and a sharp increase in the concentration of maghemite at the expense of magnetite observed for the S3, S2 and S1 paleosols provides strong evidence for a significant paleoenvironmental change. The timing of this change, based on the SK LPS age models, is compatible with the mid-Brunhes climate transition.
... Collected near volcanoes or volcanic islands, more distant tephra deposits thus provide a "history" of nearby explosive eruptions, complementing the knowledge of eruptive history determined from the study of deposits conducted in the proximal domain. Many works have demonstrated the importance of these approaches and their contribution to volcanic hazard forecasting (Watkins et al. 1978;Gehrels et al. 2006;Bertrand et al. 2008;Sulpizio et al. 2008;Insinga et al. 2014). Another use of marine and lacustrine tephra is the correlation of (distal) deposits from very large (Plinian) eruptions and relatively infrequent explosive eruptions (Pyle et al. 2006;Bazin et al. 2019). ...
... While sedimentary archives, whether marine or lacustrine, can be used in many contexts, it is probably in the Mediterranean area that the greatest number of studies is available. A chronology based on major events is now established with good accuracy, from independent sources mixing data from lake sediments (varves) and data from marine sediments (Insinga et al. 2014;Bazin et al. 2019) (Figure 1.29). Tephra layers with a wide distribution are used as a reference for further work. ...
L’impact des catastrophes naturelles est devenu une préoccupation forte de nos sociétés modernes. Parmi celles-ci, les éruptions volcaniques sont redoutées pour leurs effets dévastateurs locaux, régionaux ou globaux. Depuis le début du XXe siècle une expertise scientifique s’est progressivement développée visant à évaluer les aléas de l’activité volcanique et à suivre et prévoir les éruptions. Les capacités scientifiques dans ce domaine ont évolué avec l’accroissement des connaissances fondamentales et les développements technologiques.Aléas et surveillance de l’activité volcanique a pour but de regrouper l’ensemble des techniques et approches disponibles afin de les rendre aisément accessibles aux enseignants, aux chercheurs et aux étudiants.Ce volume est consacré aux approches géologiques et historiques. L’évaluation des aléas et la stratégie de surveillance s’appuient prioritairement sur la connaissance du comportement passé d’un volcan ou sur celui de volcans similaires. Il décrit les types d’aléas volcaniques et les approches de leur cartographie, avant de dresser un historique des techniques de surveillance.
... The X-6 is a relatively homogenous, amphibole-bearing trachytic tephra, that forms a visible layer in several Ionian Sea cores (Keller et al. 1978). X-6 has been correlated with the C-31 tephra from the Tyrrhenian Sea Insinga et al. 2014;Iorio et al. 2014) but is mainly found in the eastern Mediterranean: in the Adriatic Sea (PRAD 2812; Bourne et al. 2015) and at Tenaghi Philippon in Greece (TP05-915; Wulf et al. 2018). The X-6 is found on the Italian mainland at LGdM (TM-27; Wulf et al. 2012) and Fucino (TF-13; Giaccio et al. 2017;Mannella et al. 2019) and Sulmona (POP-4; Giaccio et al. 2012) basins and on along the Cilento coastline (CIL2 and LeS2; Giaccio et al. 2012;Donato et al. 2016). ...
... Caron et al. 2010;Vogel et al. 2010;Golovanova et al. 2010;Lane et al. 2011Lane et al. , 2015Morley and Woodward 2011;Lowe et al. 2012;Damaschke et al. 2013;Veres et al. 2013;Fitzsimmons et al. 2013;Amato et al. 2014;Douka et al. 2014;Insinga et al. 2014;Iorio et al. 2014;Engwell et al. 2014;Matthews et al. 2015;Regattieri et al. 2015;Donato et al. 2016;Ivanova et al. 2016;Leicher et al. 2016;Di Roberto et al. 2018;Mannella et al. 2019). Tephra layer thickness indicated by bubble size (closed symbol) unless unknown or cryptotephra (open symbol). ...
Layers of volcanic ash (tephra) can be used as isochronous markers linking different sedimentary archives and allowing detailed analysis of the relative timing of climatic or evolutionary events. Conversely, high-resolution sedimentary tephra archives can shed light on the geochemical evolution of magmatic systems. The last ~110 kyrs of activity at the Campi Flegrei volcanic field is punctuated by several large eruptions, including the caldera forming Campanian Ignimbrite (~40 ka) and Neapolitan Yellow Tuff (~15 ka) eruptions and the more recent Pomici Principali (~12.1 ka) and Agnano-Monte Spina (~4.5 ka) all of which are preserved in distal settings several hundred kilometres away. In addition, there are a number of important distal Campi Flegrei caldera tephra layers for which the source eruption is not known (X-5 at ~105 ka and X-6 at ~109 ka) or only recently established (Y-3; ~29 ka), indicating the occurrence of large eruptions that are unknown or poorly constrained from proximal deposits. In this contribution we discuss the dispersal and age significance of these 7 key Campi Flegrei caldera eruptions. The value of distal tephra layers is dependent on the ability to identify a distinctive geochemical fingerprint for each layer, for example, the Campanian Ignimbrite and Neapolitan Yellow Tuff events tapped zoned magma chambers and thus produced unique and compositionally variable tephra layers. Micron-beam major and trace element analyses of distal and proximal volcanic glasses allow direct distal-distal and proximal–distal tephra comparisons. In addition, good stratigraphic and chronological control is important in order to identify and correlate tephra with confidence. Here, we discuss the distinctive geochemical compositions of each of the 7 highlighted Campi Flegrei caldera marker tephra layers.
... Indeed, the recurrent and continuous explosive activity of the peri-Tyrrhenian volcanism, fed by potassic to ultrapotassic magmas (e.g., Peccerillo, 2017), as well as the presence of numerous Quaternary tectonic basins hosting thick sedimentary successions, constitute a unique combination which has allowed the retrieval of extremely rich tephra repositories and, consequently, eruption event stratigraphies. An increasing number of studies on marine (Keller et al., 1978;Paterne et al., 2008;Bourne et al., 2010Bourne et al., , 2015Tamburrino et al., 2012;Insinga et al., 2014;Morabito et al., 2014;Matthews et al., 2015;Petrosino et al., 2015Petrosino et al., , 2016D'Antonio et al., 2016), lacustrine (Wulf et al., 2004(Wulf et al., , 2008Petrosino et al., 2014a;Giaccio et al., 2015a;Di Roberto et al., 2018;Leicher et al., 2019;Regattieri et al., 2019) and sub-aerial (Giaccio et al., 2012a;Gatta et al., 2016;Donato et al., 2016;Zanchetta et al., 2018;Bini et al., 2020) sedimentary environments of the Mediterranean region have documented this potential. However, despite these recent advances, the tephrostratigraphic framework of the central Mediterranean area is still fragmentary and unexplored, especially for the Middle Pleistocene (~780-130 ka). ...
... The deep-sea core KC01B in the Ionian Sea (Fig. 1a) spans continuously the last 1.1 Ma (Lourens, 2004), but detailed tephrostratigraphic investigations are currently available only for the last 200 kyr (Insinga et al., 2014;Fig. 16). ...
Accurately reconstructing the scale and timing of dynamic processes, such as Middle-Late Pleistocene explosive volcanism and rapid climatice change, requires rigorous and independent chronological constraints. In this framework, the study of distal volcanic ash layers, or tephra, transported and deposited over wide regions during explosive volcanic eruptions, is increasingly being recognised as a fundamental chronostratigraphic tool for addressing these challenging issues. Here we present a high-resolution distal tephra record preserved in the lacustrine sedimentary succession of the Fucino Basin, central Italy. The investigated record spans the 430-365 ka time interval, covering the entirety of Marine Isotope Stage 11 (MIS 11), and provides important insights into peri-Tyrrhenian potassic explosive volcanism from sources located in central Italy against a backdrop of Mediterranean palaeooclimate records. The succession of ash fall events of this time interval is reconstructed through a detailed lithostratigraphic, geochemical and ⁴⁰Ar/³⁹Ar geochronological characterization of the deposits preserved as discrete layers in the Fucino F4-F5 sediment core. This work is complemented by similarily detailed characterization of selected proximal pyroclastic units from the peri-Tyrrhenian potassic volcanoes. Geochemical fingerprinting of the tephra deposits by means of their major, minor and trace elements and Sr isotope compositions indicates that all the thirty-two investigated ash layers derived from the peri-Tyrrhenian potassic volcanoes. The stratigraphically continuous succession of the Fucino tephra layers allowed the development of a fully independent, ⁴⁰Ar/³⁹Ar age-constrained, Bayesian age-depth model for the investigated time interval. The age-model allows us to establish modelled ages for the tephra layers within the succession that are not directly dated. The resulting dated tephra record clearly reveals a highly time resolved and previously unparalelled chronicle of explosive activity from the Vulsini, Vico, Sabatini, Colli Albani and Roccamonfina volcanic complexes. Our study provides a benchmark and valuable geochemical and geochronological dataset to be used as a reference for any future development and application of the tephrostratigraphic methods across the central Mediterranean area both during the investigated 430-365 kyr time interval, and deeper in time. This contribution underlines the importance of integrating proximal and distal sedimentary records to more accurately establish long-term and comprehensive volcanic eruption records.
... Furthermore, establishing secure chronological constraints beyond the LGC is very challenging considering limitations in numerical dating, as indicated in this study. However, a more secure regional correlation can be achieved using a tephrostratigraphical approach (Veres et al. 2013;Insinga et al. 2014;Leicher et al. 2016). In southeastern Europe, regional correlation has been widely applied relying on the L2 tephra recorded in many LPS (e.g. ...
... TF-15, TF-16, TF-17; Giaccio et al. 2017) and dated to 150-160 ka. The Mediterranean Sea tephra data also document several major tephra layers between 140-170 ka (Insinga et al. 2014). Moreover, as seen also at Batajnica, at least two tephra layers are preserved regionally within the L2 loess; this highlights the risk in deriving ages without proper geochemical control, especially when at the limit of reliable luminescence dating (Table 1). ...
The loess–palaeosol sequence of Batajnica (Vojvodina region, Serbia) is considered as one of the most complete and thickest terrestrial palaeoclimate archives for the Middle and Late Pleistocene. In order to achieve a numerical chronology for this profile, four sets of ages were obtained on 18 individual samples. Equivalent doses were determined using the SAR protocol on fine (4–11 μm) and coarse (63–90 μm) quartz fractions, as well as on polymineral fine grains by using two elevated temperature infrared stimulation methods, pIRIR290 and pIRIR225. We show that the upper age limit of coarse quartz OSL and polymineral pIRIR290 and pIRIR225 techniques is restricted to the Last Glacial/Interglacial cycle due to the field saturation of the natural signals. Luminescence ages on coarse quartz, pIRIR225 and pIRIR290 polymineral fine grains are in general agreement. Fine quartz ages are systematically lower than the coarse quartz and pIRIR ages, the degree of underestimation increasing with age. Comparison between natural and laboratory dose response curves indicate the age range over which each protocol provides reliable ages. For fine and coarse quartz, the natural and laboratory dose response curves overlap up to ~150 and ~250 Gy, respectively, suggesting that the SAR protocol provides reliable ages up to c. 50 ka on fine quartz and c. 100 ka on coarse quartz. Using the pIRIR225 and pIRIR290 protocols, equivalent doses up to ~400 Gy can be determined, beyond which in the case of the former the natural dose response curve slightly overestimates the laboratory dose response curve. Our results suggest that the choice of the mineral and luminescence technique to be used for dating loess sediments should take into consideration the reported limited reliability.
... The tephra is dated to 37.7 ka, it occurs directly above the 39 ka Campanian Ignimbrite (CI) (De Vivo et al., 2001), and it may be a widespread marker bed. Albert et al. (2017) correlated E-11 to chemically similar tephra in marine cores from the Ionian Sea as unit T1535 (Matthews et al., 2015) and I-2 (Insinga et al., 2014). Although only major element chemistry is available for tephra from these marine core units, they are probably associated with the FPdelP volcanoes on Lipari Island (Albert et al., 2017). ...
... † T1535 (Matthews et al., 2015). ‡ I-2 (Insinga et al., 2014). § Falcone and Punta del Perciato (Albert et al., 2017). ...
Chemical characterization of cryptotephra is critical for temporally linking archaeological sites. Here, we describe cryptotephra investigations of two Middle–Upper Paleolithic sites from north‐west Italy, Arma Veirana and Riparo Bombrini. Cryptotephra are present as small (<100 µm) rhyolitic glass shards at both sites, with geochemical signatures rare for volcanoes in the Mediterranean region. Two chemically distinct shard populations are present at Arma Veirana (P1 and P2). P1 is a high silica rhyolite (>75 wt.%) with low FeO (<1 wt.%) and a K2O/Na2O > 1 and P2 is also a high silica rhyolite (>75 wt.%) but with higher FeO (2.33–2.65 wt.%). Shards at Riparo Bombrini (P3) are of the same composition as P1 shards at Arma Veirana, providing a distinct link between deposits at both sites. Geochemical characteristics suggest three possible sources for P1 and P3: eruptions from Lipari Island (56–37.7 ka) in Italy, the Acigöl volcanic field (200–20 ka) in Turkey and the Miocene Kirka‐Phrigian caldera (18 Ma) in Turkey. Eruptions from Lipari Island are the most likely source for P1,3 cryptotephra. This study highlights how cryptotephra can benefit archaeology, by providing a direct link between Arma Veirana and Riparo Bombrini as well as other deposits throughout the Mediterranean.
... Furthermore, tephrochronology has also been shown to be vital in several of the recent continental (ICDP) deep drilling projects (e.g., PASADO, Wastegård et al., 2013;PALAEOVAN, Litt and Anselmetti, 2014;SCOPSCO, Leicher et al., 2016). In spite of these efforts a satisfactory and reliable tephra framework for the Mediterranean region is available only for the 200 kyr ( Bourne et al., 2010Bourne et al., , 2015Giaccio et al., 2012bGiaccio et al., , 2017Insinga et al., 2014;Paterne et al., 2008;Petrosino et al., 2016;Smith et al., 2011;Sulpizio et al., 2010;Tamburrino et al., 2012;Tomlinson et al., 2014;Wulf et al., 2004Wulf et al., , 2012Zanchetta et al., 2008Zanchetta et al., , 2018. Extending the use of tephrochronology for extra-regional to global scale chronological purposes beyond the current relatively short temporal limits of the Upper Pleistocene has thus become an urgent need. ...
... The instrument was set at an accelerating voltage of 15 kV, a 10 nA beam current, and a 3e10 mm beam with count times of 20 s for the elements Mg, P, Cl, Ti, Mn, and Fe, and 10 s for F, Na, Al, Si, K, and Ca. A range of MPI-DING reference glasses including GOR128-G (komatiite), ATHO-G (rhyolite) and StHs6/80 (andesite) ( Jochum et al., 2006) as well as natural Lipari obsidian (Hunt and Hill, 1996;Kuehn et al., 2011) were employed as secondary glass standards in order to maintain inter-laboratory consistency of analytical data. ...
Here we present the first tephrostratigraphic, palaeomagnetic, and multiproxy data from a new ~98 m-deep sediment core retrieved from the Fucino Basin, central Italy, spanning the last ~430 kyr. Palae-oenvironmental proxy data (Ca-XRF, gamma ray and magnetic susceptibility) show a cyclical variability related to interglacial-glacial cycles since the Marine Isotope Stage (MIS) 12-MIS 11 transition. More than 130 tephra layers are visible to the naked eye, 11 of which were analysed (glass-WDS) and successfully correlated to known eruptions and/or other equivalent tephra. In addition to tephra already recognised in the previously investigated cores spanning the last 190 kyr, we identified for the first time tephra from the eruptions of: Tufo Giallo di Sacrofano, Sabatini (288.0 ± 2.0 ka); Villa Senni, Colli Albani (367.5 ± 1.6 ka); Pozzolane Nere and its precursor, Colli Albani (405.0 ± 2.0 ka, and 407.1 ± 4.2 ka, respectively) and Castel Broco, Vulsini (419e490 ka). The latter occurs at the bottom of the core and has been 40 Ar/ 39 Ar dated at 424.3 ± 3.2 ka, thus providing a robust chronological constrain for both the eruption itself and the base of the investigated succession. Direct 40 Ar/ 39 Ar dating and tephra geochemical fingerprinting provide a preliminary radioisotopic-based chronological framework for the MIS 11-MIS 7 interval, which Quaternary Science Reviews 225 (2019) 106003 represent a foundation for the forthcoming multiproxy studies and for investigating the remaining ~110 tephra layers that are recorded within this interval. Such future developments will contribute towards an improved MIS 11-MIS 7 Mediterranean tephrostratigraphy, which is still poorly explored and exploited.
... Mediterranean deep-sea records, on the other hand, have rarely been examined for their (crypto)tephra content so far. The only marine records in the Central Mediterranean with detailed tephrostratigraphies spanning the MIS1 to MIS 5 time period are cores PRAD 1-2 from the Adriatic Sea (Bourne et al., 2010 and KC01B from the Ionian Sea (Insinga et al., 2014;Lourens, 2004); these cores register a number of tephra layers in common with TP (e.g. Y-3, CI, TM-23-11, and X-6; Fig. 13) but lack high-resolution proxy data. ...
... Green and blue columns indicate archives from terrestrial and marine environments, respectively. The archives included are (from west to east): Fucino (Giaccio et al., 2017b); Sulmona ; core PRAD 1-2, Adriatic Sea (Bourne et al., 2010; Lago Grande di Monticchio ; core KC01B, Ionian Sea (Insinga et al., 2014); Lake Ohrid (Leicher et al., 2016); Tenaghi Philippon (core TP-2005; Albert et al., 2015;Müller et al., 2011;Pross et al., 2015; this study); core LC21, South Aegean Sea (Satow et al., 2015). (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.) ...
The iconic climate archive of Tenaghi Philippon (TP), NE Greece, allows the study of short-term palaeoclimatic and environmental change throughout the past 1.3 Ma. To provide high-quality age control for detailed palaeoclimate reconstructions based on the TP archive, (crypto)tephra studies of a peat core ‘TP-2005’ have been carried out for the 0–130 ka interval. The results show that the TP basin is ideally positioned to receive tephra fall from both the Italian and Aegean Arc volcanic provinces. Two visible tephra layers, the Santorini Cape Riva/Y-2 (c. 22 ka) and the Campanian Ignimbrite (CI)/Y-5 (c. 39.8 ka) tephras, and six primary cryptotephra layers, namely the early Holocene E1 tephra from the Aeolian Islands (c. 8.3 ka), the Campanian Y-3 (c. 29 ka) and X-6 tephras (c. 109.5 ka), as well as counterpart tephras TM-18-1d (c. 40.4 ka), TM-23-11 (c. 92.4 ka) and TM-33-1a (c. 116.7 ka) from the Lago Grande di Monticchio sequence (southern Italy), were identified along with repeatedly redeposited Y-2 and CI tephra material. Bayesian modelling of the ages of seven of the primary tephra layers, 60 radiocarbon measurements and 20 palynological control points have been applied to markedly improve the chronology of the TP archive. This revised chronology constrains the age of tephra TM-18-1d to 40.90–41.66 cal ka BP (95.4% range). Several tephra layers identified in the TP record form important isochrons for correlating this archive with other terrestrial (e.g., Lago Grande di Monticchio, Sulmona Basin and Lake Ohrid) and marine (e.g., Adriatic Sea core PRAD 1-2 and Aegean Sea core LC21) palaeoclimate records in the Mediterranean region.
... This has raised issues surrounding the correlation of distal counterparts retrieved in marine and lacustrine sediments in different sectors of the Mediterranean region, e.g. Lago di Mezzano (central Italy; Ramrath et al. 1999;Wulf et al. 2008), Lago Grande di Monticchio (southern Italy; Wulf et al. 2004Wulf et al. , 2008, Tyrrhenian Sea (Paterne et al. 1988;Tamburrino et al. 2016), Adriatic Sea (Siani et al. 2001(Siani et al. , 2004, Ionian Sea (Insinga et al. 2014), Bannock Basin (Mediterranean Sea; Vezzoli 1991) and Haua Fteah (northern Libya; Douka et al. 2014) which are either labelled as Y-1 or Et-1 (Keller et al. 1978;Vezzoli 1991;Calanchi et al. 1998;Ramrath et al. 1999;Siani et al. 2001Siani et al. , 2004Wulf et al. 2004Wulf et al. , 2008Insinga et al. 2014). Proximal-distal and distaldistal glass geochemical correlations and chronological constraints indicate a complex range of tephra dispersals from Etna volcano during the Last Glacial-Interglacial transition. ...
... This has raised issues surrounding the correlation of distal counterparts retrieved in marine and lacustrine sediments in different sectors of the Mediterranean region, e.g. Lago di Mezzano (central Italy; Ramrath et al. 1999;Wulf et al. 2008), Lago Grande di Monticchio (southern Italy; Wulf et al. 2004Wulf et al. , 2008, Tyrrhenian Sea (Paterne et al. 1988;Tamburrino et al. 2016), Adriatic Sea (Siani et al. 2001(Siani et al. , 2004, Ionian Sea (Insinga et al. 2014), Bannock Basin (Mediterranean Sea; Vezzoli 1991) and Haua Fteah (northern Libya; Douka et al. 2014) which are either labelled as Y-1 or Et-1 (Keller et al. 1978;Vezzoli 1991;Calanchi et al. 1998;Ramrath et al. 1999;Siani et al. 2001Siani et al. , 2004Wulf et al. 2004Wulf et al. , 2008Insinga et al. 2014). Proximal-distal and distaldistal glass geochemical correlations and chronological constraints indicate a complex range of tephra dispersals from Etna volcano during the Last Glacial-Interglacial transition. ...
Pumice fall deposits found in the Nebrodi Mountains and along the Alcantara River, close to the town of Randazzo (NE Sicily), have been studied to derive information about their volcanic source and age. The geochemical Na-alkaline affinity of juvenile products, benmoreite to trachyte, clearly indicates they originated from Etna volcano (Sicily). Major (EMPA) and trace (LA-ICP-MS) element compositional data on matrix glasses indicate that the investigated deposits have a compositional affinity consistent with the tephra deposits of unit D produced by the Ellittico caldera-forming eruptions between ca. 17 and 19 cal ka BP. Furthermore, their compositions correspond to the distal tephra equivalent found in some lacustrine and marine cores in Central Italy (Y-1, TM-11), Tyrrhenian Sea (Et-1; MD10α) and Adriatic Sea (Pal94-66-358; Pal94-8-353). We applied the principal components analysis (PCA), a statistical tool able to reduce the variability of a complex system, to compare the compositions of the proximal samples with the possible distal counterparts found in drill cores of the Mediterranean area. On the basis of northward dispersal of the studied deposits and their geochemical features, we suggest they represent a previously unreported sub-Plinian/Plinian eruption of Ellittico volcano producing medial-distal pumice fall deposits in the Nebrodi Mountains and close to Randazzo, named here the D1c layer. The discovery of these deposits helps solve the problem of distal correlations of the northerly dispersed tephra from Etna related to unit D, for which no definitive attribution with proximal units was given in previous studies. The results presented here add to the knowledge of the eruptive history of the volcano and contribute to expanding the proximal geochemical glass dataset for distal tephra correlation in the Mediterranean region during the Late Glacial period.
... The Y-5 layer, a distal ash layer in the eastern Mediterranean, extensively studied and identified in marine cores, rockshelters, and lake and peat basins, is an important datum and is correlated with the 39.3 ka Campanian Ignimbrite (St. Seymour et al., 2004;Pyle et al., 2006;Di Vito et al., 2008;Morley and Woodward, 2011;Insinga et al., 2014;Morabito et al., 2014). The last 20 years have seen an almost exponential increase in tephrochronology publications (e.g., Munno and Petrosino, 2007;Paterne et al., 2008;Lane et al., 2011;Riede and Thastrup, 2013;Insinga et al., 2014), especially related to Eastern Mediterranean volcanism. ...
... Seymour et al., 2004;Pyle et al., 2006;Di Vito et al., 2008;Morley and Woodward, 2011;Insinga et al., 2014;Morabito et al., 2014). The last 20 years have seen an almost exponential increase in tephrochronology publications (e.g., Munno and Petrosino, 2007;Paterne et al., 2008;Lane et al., 2011;Riede and Thastrup, 2013;Insinga et al., 2014), especially related to Eastern Mediterranean volcanism. While beyond the scope of this paper to attempt to correlate, the age range and number of tephra layers linked to the Campanian Plain is relevant as further information on the approximate number of eruptions and how far back they extend. ...
The Campanian Plain in southern Italy has been volcanically active for at least the last 300 ka. The Campanian Ig-nimbrite (CI) erupted at 39.3 ka, has a volume of ≥310 km 3 and a great areal extent. However, significant, but scattered deposits of older ignimbrites underlie the CI and document a long history of volcanism. We examined the mineralogy and geochemistry of 11 older ignimbrite strata by optical petrography, electron microprobe, scanning electron microscope, X-ray diffraction, and various whole-rock geochemical techniques. We have analyzed strata at Durazzano (116.1 ka), Moschiano (184.7 ka), Seiano Valley (245.9 and 289.6 ka), and Taurano — Acqua Feconia (157.4, 183.8, 205.6, and 210.4 ka) that have been previously dated on unaltered sanidine. The older ig-nimbrites are highly altered with loss on ignition (LOI) that ranges from 17 to 8 wt%. Whole-rock compositions reflect variable element mobility during weathering; e.g., CaO is enriched and Na 2 O depleted relative to hydra-tion. X-ray diffraction identified major chabazite, kaolinite, and illite alteration products in some samples. Rhabdophane-(Nd), usually intergrown with chabazite and Mn-carbonate, indicates that some LREE were also mobilized during weathering. The phenocryst mineralogy is typical for Campanian Plain (CP) magmas and consists of plagioclase (, biotite (TiO 2 = ~4–7 wt%, BaO = up to 2 wt%, F = up to 2 wt%), diopside (Ca 47 Mg 47 Fe 6 to Ca 48 Mg 29 Fe 23), and titanifer-ous magnetite. Relatively immobile trace elements Zr, Hf, Th, Ta, V, and Nb were used to investigate element abundance and ratio compared to the Campanian Ignimbrite and other CP magmas. Zr/Hf of the older ignimbrites is similar to that of the CI, but Ta is depleted relative to Th and V is enriched compared to CI. Th/Ta and Nb/V distributions for most of the older ignimbrites are similar to those in the Neapolitan Yellow Tuff with the exception of the sample MS-1 from Moschiano that is more evolved and similar to Campanian Ignimbrite. All older ignim-brite Zr/Hf (w/w) and many Nb/Ta (w/w) ratios are superchondritic that suggests that the older ignimbrites represent fractional crystallization products of parental magmas generated from enriched mantle without significant addition of continental crust.
... knowledge of the explosive volcanic history of a region and a comprehensive volcanic glass geochemical data set of the different eruptions are both needed. The Mediterranean region offers suitable conditions for tephrostratigraphy and tephrochronology, which has led to the development of a comprehensive and continuously expanding tephrostratigraphic framework (Keller et al. 1978;Paterne et al. 2008;Zanchetta et al. 2011;Wulf et al. 2012;Insinga et al. 2014;Petrosino et al. 2015;Giaccio et al. 2015aGiaccio et al. , 2017bVakhrameeva et al. 2018Vakhrameeva et al. , 2021Leicher et al. 2019Leicher et al. , 2021McGuire et al. 2022;Monaco et al. 2022b). However, the tephrostratigraphic framework >100 ka is still fragmentary. ...
In the lacustrine succession F4‐F5 of the Fucino Basin, central Italy, 20 visible tephra layers were identified in the time interval 250–315 ka (Marine Isotope Stages 8–9). Fifteen of them contained suitable material to explore their volcanic sources. Among these tephra some well‐known eruptions and eruptive sequences of the Roman and Roccamonfina volcanoes were identified, such as the Tufo Giallo di Sacrofano and the Lower White Trachytic Tuff, respectively. Furthermore, the sediment succession documents a more complex eruptive history of the Sabatini, Vulsini, Colli Albani and Roccamonfina volcanic complexes during the investigated period, as inferred from previously undescribed tephra deposits. Single‐crystal‐fusion ⁴⁰ Ar/ ³⁹ Ar dating of two of the inspected tephra layers combined with two already published tephra ages provided the basis for a Bayesian age‐depth model. The modelled tephra ages allow chronological constraining of so‐far undefined eruptions of the Sabatini (272.5±4.7, 281.8±4.7, 308.5±2.8, 312.8±2.1 ka), the Vulsini (311.7±2.3, 311.9±2.3 ka) and the Colli Albani (301.0±3.6 ka) volcanic districts. Two tephra layers of an undefined volcanic source from the Roman volcanoes have modelled ages of 309.5±2.7 and 310.5±2.6 ka. The new ⁴⁰ Ar/ ³⁹ Ar and modelled ages were further used for a reassessment of the timing of already known and dated eruptive units, such as the Tufo Giallo di Sacrofano ( ⁴⁰ Ar/ ³⁹ Ar: 289.3±4.8 ka). Tephra tentatively correlated with the Valle Santa Maria, Case Pisello and the White Trachytic Tuff Unit E3 or Unit F offer modelled ages for these eruptions of 296.6±3.9, 301.8±3.5 and 303.6±3.4 ka, respectively. The results complete the tephrostratigraphical investigations of the c. 425 ka old F4‐F5 record, extend the Mediterranean tephrostratigraphical framework and provide a significant contribution for improving knowledge on Italian volcanic explosive activity.
... The first detailed tephrostratigraphical framework based on marine sediment successions was established in the Mediterranean region in the 1970s (Keller et al. 1978) and has been continuously refined since then by including terrestrial sequences (e.g. Paterne et al. 1988Paterne et al. , 2008Narcisi & Vezzoli 1999;Wulf et al. 2004Wulf et al. , 2008Wulf et al. , 2012Calanchi & Dinelli 2008;Albert et al. 2012;Tamburrino et al. 2012Tamburrino et al. , 2016Giaccio et al. 2013a;Insinga et al. 2014;Petrosino et al. 2014Petrosino et al. , 2019Bourne et al. 2015;Zanchetta et al. 2019). Tephrostratigraphical and tephrochronological studies in the Mediterranean are often applied for chronological purposes within the scope of palaeoenvironmental, palaeoclimatic and/or archaeological investigations (e.g. ...
Thirty‐two tephra layers were identified in the time‐interval 313–366 ka (Marine Isotope Stages 9–10) of the Quaternary lacustrine succession of the Fucino Basin, central Italy. Twenty‐seven of these tephra layers yielded suitable geochemical material to explore their volcanic origins. Investigations also included the acquisition of geochemical data of some relevant, chronologically compatible proximal units from Italian volcanoes. The record contains tephra from some well‐known eruptions and eruptive sequences of Roman and Roccamonfina volcanoes, such as the Magliano Romano Plinian Fall, the Orvieto–Bagnoregio Ignimbrite, the Lower White Trachytic Tuff and the Brown Leucitic Tuff. In addition, the record documents eruptions currently undescribed in proximal (i.e. near‐vent) sections, suggesting a more complex history of the major eruptions of the Colli Albani, Sabatini, Vulsini and Roccamonfina volcanoes between 313 and 366 ka. Six of the investigated tephra layers were directly dated by single‐crystal‐fusion 40Ar/39Ar dating, providing the basis for a Bayesian age–depth model and a reassessment of the chronologies for both already known and dated eruptive units and for so far undated eruptions. The results provide a significant contribution for improving knowledge on the peri‐Tyrrhenian explosive activity as well as for extending the Mediterranean tephrostratigraphical framework, which was previously based on limited proximal and distal archives for that time interval.
... In the earlier studies, these tephra were thought be generated in a poorly defined Neapolitan-Campanian volcanic area (e.g., Keller et al., 1978;Paterne et al., 1986), but recently they have been attributed to previously unknown 92-109 ka Campi Flegrei activity (Monaco et al., 2022). These tephra are widely spread in the central Mediterranean area and represent important tephrochronological markers for marine isotope stage 5 in both terrestrial (Donato et al., 2016;Giaccio et al., 2012Giaccio et al., , 2017Giaccio et al., , 2012Leicher et al., 2016;Marciano et al., 2008;Petrosino et al., 2019;Regattieri et al., 2015;Sulpizio et al., 2010;Wulf et al., 2012Wulf et al., , 2018) and marine settings (; Bourne et al., 2010, 2015Bourne et al., 2015Insinga et al., 2014;Iorio et al., 2014;Paterne et al., 1988Paterne et al., , 2008. With a conventional approach such as the use of a TAS diagram and binary scatterplots of element oxides, the discrimination between the products of Somma-Vesuvius, Campi Flegrei, and Ischia and the correlation with studied tephra is not unambiguous, owing to the large compositional heterogeneity of Somma-Vesuvius products ( Fig. 4A and B). ...
Tephrostratigraphic correlations commonly rely on geochemical composition supported by additional constraints (e.g., multiple stratigraphically ordered tephra, geochronological-stratigraphical constraints, and isotopic determinations), which provide key clues to restrict the number of possible candidates and disambiguate the correlation of a specific tephra among compositionally similar volcanic sources/tephra. However, such additional data may not be available or acquirable, leaving the geochemical data as sole, but challenging viable approach. In this study, two geochronologically poorly constrained late Pleistocene tephra from the eastern Adriatic –from a sand profile on Mljet Island (M-53/2) and from a marine sediment core from Pirovac Bay (PROS 721)– were correlated to known eruptions using only geochemical data (major and trace elements of glass shards), which were treated using both log ratio transformed and raw data. After the statistical treatment of the geochemical data using bivariate plots, linear discrimination analyses and selbal algorithm, the tephra M-53/2 and PROS 721 were suitably correlated with the widespread tephra generated during the Campi Flegrei eruptions of Massereia del Monte (Y-3 marine tephra, 29.0 ± 0.8 ka) and Neapolitan Yellow Tuff (14.5 ± 0.4 ka), respectively. This study showed that the correlation was hardly tenable when using the raw data, as opposed to compositional approach, which yielded satisfactory results. As a consequence, the distribution of Massereia del Monte/Y-3 tephra extended far toward the northeast, while a better chronological model, for reconstructing the paleoenvironmental changes at the Pirovac Bay location and the Holocene sea-level dynamics, could be obtained.
... The NYT deposits were identified in the Gulf of Pozzuoli and in the northern Phlegraean Fields offshore [12,14,20,58,[78][79][80]. Pyroclastic deposits represent main stratigraphic markers in the marine sedimentary record [81][82][83] and were documented on the Campania continental margin [84][85][86][87][88]. A continuous seismic reflector mapped in the northern Phlegraean offshore was correlated with the NYT deposits [21]. ...
The submarine stratigraphy of the eastern Bay of Naples is studied through seismo�stratigraphic data correlated with borehole data. Multichannel seismic profiles are interpreted in order to reconstruct the stratigraphic relationships between the Quaternary marine seismic units and the volcanic acoustic substratum. Seven seismic units are recognized based on the geological interpretation of seismic profiles and using seismo-stratigraphic criteria. The top of the lowest seismic unit was correlated with the Campanian Ignimbrite (Southern Campania Volcanic Zone). The stratigraphic setting of the eastern Bay of Naples is characterized by NE-SW trending seismic structures, probably corresponding with tuff rings. These tuff rings can be compared with the Porto Miseno, the Archiaverno and Averno, and the Astroni tuff rings (Campi Flegrei). Offshore, the Somma-Vesuvius a seismic unit was interpreted as the fallout deposits representing the base of the AD 79 eruption. However, since a branch of the isopach of 5 m of the “Pomici di Avellino” pyroclastic deposits is very close to the Tyrrhenian coastline and near our GRNA01 and GRNA03 seismic profiles, we cannot exclude that the seismic unit could be also correlated with the deposits of this eruption.
... Simplified summary diagram of key tephra horizons within the Mediterranean tephrostratigraphic framework for the past 50 ka. Archives included here are: Tyrrhenian Sea (Paterne et al., 1988;Albert et al., 2012), Lago Grande di Monticchio (Wulf et al., 2004, Adriatic Sea (Bourne et al., 2010;Matthews et al., 2015), Ionian Sea (Keller et al., 1978;Albert et al., 2012;Insinga et al., 2014), Lake Ohrid (Wagner et al., 2008;Vogel et al., 2010;Sulpizio et al., 2010;Leicher et al., 2016), Lake Ioannina (this study), Tenaghi Philippon (Wulf et al., 2018), the Aegean Sea (Satow et al., 2015), and Megali Limni (Margari et al., 2007). Eruption ages from Bronk Ramsey et al. (2015) other than Agnano Mt Spina (Smith et al., 2011), Vallone del Gabellotto (E-1) (Albert et al., 2019), Mercato (Santacroce et al., 2008) and Pantelleria Green Tuff (Y-6) . ...
Terrestrial archives from the Mediterranean have been crucial to expanding our understanding of past environmental variability on a range of timescales. Dating Quaternary sequences in the Mediterranean is, however, often challenging, and age models often have large chronological uncertainties. Tephra deposits can provide crucial age control for detailed environmental reconstructions on sub‐centennial timescales. Here, tephra analysis is undertaken for the first time on a sediment core (I‐08) from Lake Ioannina, northwest Greece, for the interval spanning 46–4 ka bp. Detailed visible and ‘crypto‐’ tephra analysis identifies deposits associated with explosive volcanism at Italian volcanic sources, including Campi Flegrei, Pantelleria, and the Aeolian Islands. We identify two visible tephra layers, the Campanian Ignimbrite (CI/Y‐5; ca. 39.8 ka bp) and Pantelleria Green Tuff (PGT/Y‐6; ca. 45.7 ka), as well as the Holocene Vallone del Gabellotto cryptotephra marker (VG/E‐1; ca. 8.3 ka bp). Evidence for repeated remobilisation and redeposition of CI tephra material is outlined, and the potential mechanisms and effects of sediment reworking in lake environments are examined. Bayesian modelling, which incorporates the new tephra ages with earlier radiocarbon dates, extends the I‐08 core chronology back to ca. 46 ka bp, facilitating direct correlation of the Ioannina sequence to others in the Mediterranean region.
... tephrostratigraphic framework in the Mediterranean region of the last ca. 200 ka [13][14][15][16][17][18][19] . To extend this framework, 57 tephra layers of the DEEP site ( Fig. 1) were characterized by their morphological and glass geochemical properties 2,14,[20][21][22][23] . ...
Tephrochronology relies on the availability of the stratigraphical, geochemical and geochronological datasets of volcanic deposits, three preconditions which are both often only fragmentary accessible. This study presents the tephrochronological dataset from the Lake Ohrid (Balkans) sediment succession continuously reaching back to 1.36 Ma. 57 tephra layers were investigated for their morphological appearance, geochemical fingerprint, and (chrono-)stratigraphic position. Glass fragments of tephra layers were analyzed for their major element composition using Energy-Dispersive-Spectroscopy and Wavelength-Dispersive Spectroscopy and for their trace element composition by Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry. Radiometric dated equivalents of 16 tephra layers and orbital tuning of geochemical proxy data provided the basis for the age-depth model of the Lake Ohrid sediment succession. The age-depth model, in turn, provides ages for unknown or undated tephra layers. This dataset forms the basis for a regional stratigraphic framework and provides insights into the central Mediterranean explosive volcanic activity during the last 1.36 Ma.
... Somma-Vesuvius, Campi Flegrei and Ischia Island (Santacroce et al. 2008;Smith et al. 2011;Tomlinson et al. 2012, among others). Moreover, the rich dataset of Upper Pleistocene-Holocene distal tephra has been used for comparison (Wulf et al. 2004;Munno and Petrosino 2007;Insinga et al. 2014). Average composition of glasses extracted from the investigated samples has been reported in Table 4 together with the composition of possible correlatives. ...
Two boreholes, both about 16 m-deep, have been drilled in the Garigliano Plain, a coastal-alluvial plain located at the boundary between southern Latium and northern Campania, Italy. The drill holes have been planned and carried out in the southern part of the plain, near to the bordering ridge of Mount Massico. The multidisciplinary analyses performed on sediment samples from both cores revealed the presence of several marine and continental sedimentation environments, transitional facies and volcanic rocks. All these data, together with the stratigraphic correlation between the two logs, allowed the reconstruction of the sedimentary and morphological evolution of the plain during the Late Quaternary. Further, such an evolutionary sequence has been used as a comparison scheme with regard to other coastal plains of the Tyrrhenian side of central and southern Italy to stress similar or different behaviours among them on a distance of about 400 km of coastal belt. Some remarkable differences have been actually enlighten, with particular reference to the MIS 5.5 and the Holocene.
The occurrence in both cores of products of the Campanian Ignimbrite – a ~ 40 ka pyroclastic unit – and associated reworked deposits (about five metres-thick in both cases), has been here reported for the first time in the subsurface of the southern part of the Garigliano Plain. In addition, a tephra layer has been detected at −14.50 m of depth (i.e. 13.50 m a.s.l.) in the northernmost core. This layer has been ⁴⁰Ar/³⁹Ar dated at 124.5 ± 0.5 ka. In the upper part of the same drill core, deposits interpreted as lagoonal-swamp facies have been recognized. On the basis of ¹⁴C dating, we can attribute the starting stage of such a sedimentation to the effects induced by the Post-glacial sea-level rise at about 8000 yr BP. These chronological constraints permitted us to obtain from the paleoecological, palynological, and granulometric analyses of the sampled successions helpful and precise information about sea-level changes along that coastal belt.
... Considering the U/Th chronology and archaeological constraints, the tephra Inf-1 in LU-7 should be younger than~115 ka and likely older than~40 ka (late Marine Isotope Stage 3, MIS 3), which is the uppermost limit of the Mousterian (Higham et al., 2014). The tephra could thus be associated with a number of Campi Flegrei, or Campi Flegrei-like, tephras known from the 115e40 ka interval, among which the Campanian Ignimbrite (CI), C-22, X-5 and X-6 are the most widespread (e.g., Bourne et al., 2010;2015;Wulf et al., 2012;Giaccio et al., 2012;Insinga et al., 2014;Sulpizio et al., 2010;Tomlinson et al., 2015;Leicher et al., 2016). ...
The timing, duration and evolution of sea level during the Marine Isotope Stage 5e (MIS 5e) highstand is a subject of intense debate. A major problem in resolving this debate is the difficulty of chronologically constraining the sea level fall that followed the peak of the highstand. This was mainly controlled by ice-sheet dynamics, the understanding of which is relevant for assessing future sea-level behavior due to global warming. Here we use stratigraphical and geochoronological (U/Th dating and tephra fingerprinting) evidence from the Infreschi archaeological cave (Marina di Camerota, Southern Italy) to constrain relative sea level (RSL) evolution during the MIS 5e highstand and younger stages. Uranium-thorium dating of speleothem deposition phases places the maximum highstand RSL at 8.90 ± 0.6 m a.s.l., as indicated by the near-horizontal upper limit of Lithophaga boreholes measured for along ã 3.5 km coastal cliff section. Geochronological data show that RSL fell more than 6 m before~120 ka, suggesting a duration of the Last Interglacial highstand significantly shorter than proposed in some previous studies. Modelling shows that the RSL trend predicted by the ICE-5G and ICE-6G ice-sheet simulations is consistent with our data, but requires an additional significant reduction of both Greenland and Antarctic ice sheets to match the height of the local maximum highstand if no correction for tectonics is applied. Reconciling field data and models requires an earlier and likely shorter duration of the MIS 5e highstand. This suggests that our new data can constrain global ice-volume variations during the penultimate deglaciation, as well as glacial inception at the end of the Last Interglacial. According to our chronology, there is no local evidence of higher-than-present-day sea levels after 120 ka.
... Through radioisotope dating and geochemical fingerprinting of tephra layers interbedded within sedimentary archives, tephrochronology allows the correlation of palaeoenvironmental records and their integration in a coherent chronological framework, independent of orbital tuning approaches (e.g., Giaccio et al., 2015;Mannella et al., 2017Regattieri et al., 2014;Wulf et al., 2018;Zanchetta et al., 2011. Equally significant are the applications of the distal tephrostratigraphy for volcanological purposes, which, through the integration of the data collected in near-source areas, allows to improve the knowledge of the eruptive history and dynamics of adjoining volcanoes (e.g., Paterne et al., 2008;Costa et al., 2012;Insinga et al., 2014;Petrosino et al., 2014;Bourne et al., 2015;Albert et al., 2019;Wulf et al., 2012Wulf et al., , 2020. ...
Through a systematic integrated approach, which combined lithostratigraphic, geochronological and geochemical analyses of tephra from near-source sections of the peri-Tyrrhenian volcanoes and mid to distal settings, here we provide an improved tephrochronological framework for the Marine Isotope Stage 11c interglacial (MIS 11c, ∼425–395 ka) in the Central Mediterranean area. Specifically, we present the complete geochemical dataset and new high-precision ⁴⁰Ar/³⁹Ar ages of the previously poorly characterized earliest pyroclastic products of the Vico volcano (420–400 ka), including the Plinian eruptions of Vico α and Vico β and the immediately post-dating lower magnitude explosive events. Furthermore, we also provide new geochronological and geochemical data for the distal tephra layers preserved in the aggradational succession of the Tiber delta (San Paolo Formation), Roman area, which records sea level rise relating to the MIS 12 (glacial) to MIS 11 (interglacial) transition. Five pyroclastic units were recognized in Vico volcanic area, four out of which, Vico α, Vico β, Vico βtop (a minor eruption immediately following Vico β and temporally very close to it) and Vico δ were directly dated at 414.8 ± 2.2 ka, 406.5 ± 2.4 ka, 406.4 ± 2.0 ka and 399.7 ± 3.2 ka respectively (2σ analytical uncertainties). These new data allow a critical reappraisal of the previously claimed identifications of Vico tephra from mid-distal to ultra-distal successions (i.e., Vico-Sabatini volcanic districts, Roman San Paolo Formation and Castel di Guido archaeological site, Sulmona Basin, Valdarno and Lake Ohrid), which were unavoidably biased by the poor and incomplete geochemical and geochronological reference datasets previously available. Such an improvement of the tephrochronological framework brings great benefits to any future investigations (e.g., paleoclimatology, archaeology, active tectonic, volcanology) in the dispersal areas of the studied eruptions at the key point in time that is MIS 11.
... figure 1 for position of sites. Core and tephra data derive from: Fucino palaeolake, central Italy [90]; Sulmona palaeolake, central Italy [92]; PRAD 1-2, central Adriatic Sea [5,30]; Lago Grande di Monticchio, southern Italy [4]; KC01B, Ionian Sea [46]; Lake Ohrid, Albany/Macedonia [93]; Tenaghi Philippon, northeastern Greece [32]; LC21, KL51 and ODP967B (this study). Positions of sapropels S3-S5 are included for comparison. ...
The Eemian was the last interglacial period (~130 to 115 ka BP) to precede the current interglacial. In Eastern Mediterranean marine sediments, it is marked by a well-developed and organic-rich “sapropel” layer (S5), which is thought to reflect an intensification and northward migration of the African monsoon rain belt over orbital timescales. However, despite the importance of these sediments, very little proxy-independent stratigraphic information is available to enable rigorous correlation of these sediments across the region. This paper presents the first detailed study of visible and non-visible (cryptotephra) layers found within these sediments at three marine coring sites: ODP Site 967B (Levantine Basin), KL51 (South East of Crete) and LC21 (Southern Aegean Sea). Major element analyses of the glass component were used to distinguish four distinct tephra events of Santorini (e.g., Vourvoulos eruption) and possible Anatolian provenance occurring during the formation of S5. Interpolation of core chronologies provides provisional eruption ages for the uppermost tephra (unknown Santorini, 121.8 ± 2.9 ka) and lowermost tephra (Anatolia or Kos/Yali/Nisyros, 126.4 ± 2.9 ka). These newly characterised tephra deposits have also been set into the regional tephrostratigraphy to illustrate the potential to precisely synchronise marine proxy records with their terrestrial counterparts, and also contribute to the establishment of a more detailed volcanic history of the Eastern Mediterranean.
... Ideally, these tephrostratigraphies encompass complete sequences of past eruptive events in stratigraphic order, high-precision dating, and comprehensive glass geochemical datasets of erupted tephras from proximal (i.e., near-vent) settings that enable detailed correlations with distal deposits. In Europe, such tephrostratigraphies are well established for Holocene and Lateglacial Icelandic volcanoes (e.g., Larsen and Eiriksson, 2008;Lawson et al., 2012;Davies et al., 2014;Gudmundsdóttir et al., 2016;Wastegård et al., 2018) and for the Italian volcanic peninsula dating back to ∼800 ka (e.g., Narcisi and Vezzoli, 1999;Wulf et al., 2004;Santacroce et al., 2008;Zanchetta et al., 2011;Wulf et al., 2012;Insinga et al., 2014;Albert et al., 2017;Giaccio et al., 2017a). In contrast, tephrostratigraphies are still fragmentary for the Eastern Mediterranean region. ...
The island of Santorini in the Aegean Sea is one of the world’s most violent active volcanoes. Santorini has produced numerous highly explosive eruptions over at least the past ∼360 kyrs that are documented by the island’s unique proximal tephra record. However, the lack of precise eruption ages and comprehensive glass geochemical datasets for proximal tephras has long hindered the development of a detailed distal tephrostratigraphy for Santorini eruptions. In light of these requirements, this study develops a distal tephrostratigraphy for Santorini covering the past ∼360 kyrs, which represents a major step forward towards the establishment of a tephrostratigraphic framework for the Eastern Mediterranean region. We present new EPMA glass geochemical data of proximal tephra deposits from twelve Plinian and numerous Inter-Plinian Santorini eruptions and use this dataset to establish assignments of 28 distal marine tephras from three Aegean Sea cores (KL49, KL51 and LC21) to specific volcanic events. Based on interpolation of sapropel core chronologies we provide new eruption age estimates for correlated Santorini tephras, including dates for major Plinian eruptions, Upper Scoriae 1 (80.8 ± 2.9 ka), Vourvoulos (126.5 ± 2.9 ka), Middle Pumice (141.0 ± 2.6 ka), Cape Thera (156.9 ± 2.3 ka), Lower Pumice 2 (176.7 ± 0.6 ka), Lower Pumice 1 (185.7 ± 0.7 ka), and Cape Therma 3 (200.2 ± 0.9 ka), but also for 17 Inter-Plinian events. Older Plinian and Inter-Plinian activity between ∼310 ka and 370 ka, documented in the distal terrestrial setting of Tenaghi Philippon (NE Greece), is independently dated by palynostratigraphy and complements the distal Santorini tephrostratigraphic record.
... The present-day shape of the caldera has been conventionally interpreted as the result of two large collapses related to the eruptions of the Campanian Ignimbrite (CI, ∼ 39 ka; Giaccio et al., 2017) and the Neapolitan Yellow Tuff (NYT, ∼ 15 ka; Deino et al., 2004) (Fig. 2) with respective volumes of 200 km 3 DRE (dense-rock equivalent) (Rolandi et al., 2003) and 40 km 3 DRE (Scarpati et al., 1993). Evidence of older ignimbrites has been reported in the Campanian Plain (De Vivo et al., 2001) and in the distal marine archives (e.g., Insinga et al., 2014). The locations of these eruptions remain poorly constrained around Campi Flegrei. ...
Active calderas are the major volcanic features of the Earth's. They are associated with large magma reservoirs and are characterized by elevated geothermal gradients. Unrest episodes, often documented through historical times, are not always followed by an eruption; however, every eruption is preceded by unrest. Explosive caldera-forming eruptions are 30 among the most catastrophic events on our planet. These eruptions result from the withdrawal and collapse of huge magma chambers and produce large volumes of pyroclastic deposits and later-stage deformations related to post-caldera resurgence and volcanism. Campi Flegrei caldera (CFc), located along the eastern Tyrrhenian coastline, is close to the densely populated area of Naples. It is one of the most dangerous volcanoes on Earth and represents a key example of an active, resurgent caldera, as proven by 35 ongoing unrest involving ground deformation, seismicity, and hydrothermal activity. Campi Flegrei has been traditionally interpreted as a nested caldera formed by collapses associated with two main eruptions: the 100-200 km 3 Campania 2 Ignimbrite (CI), ~ 39 ka BP, which is regarded as Europe's largest and most devastating eruption of the past 200 kyrs (Barberi et al., 1978; Lirer et al., 1987; Rosi and Sbrana, 1987; Orsi et al, 1996; De Vivo et al., 2001; Deino et al., 2004), and the 40 km 3 eruption of the Neapolitan Yellow Tuff (NYT) at ~ 15 ka BP (Deino et al., 2004). Recent studies have suggested 40 that the CI may instead have been fed by fissural eruption(s) from the Campania Plain, north of Campi Flegrei (e.g. Rolandi et al., 2003). In order to discuss the potential of the CFc as target for an amphibious drilling project within the IODP-ICDP Programs, a MagellanPlus workshop was held in Naples, Italy on 25-28 February 2017. The main result of the workshop has been a general consensus on the representativeness of the CFc as target of active, resurgent calderas worldwide. Campi Flegrei is 45 the ideal site to investigate the mechanisms of caldera formation and post-caldera dynamics and analyze the still poorly known interplay between hydrothermal and magmatic processes and the role of such processes on the mechanisms of unrest. We develop a coordinated onshore-offshore drilling strategy to reconstruct the structure and evolution of the Campi Flegrei volcanic system and to investigate the precursors of volcanic activity by examining a) the succession of volcanic and hydrothermal products and related processes, b) the inner structure of the caldera resurgence, c) the physical, chemical and 50 biological characters of the hydrothermal system and offshore sediments and d) the geological expression of the phreato-and hydro-magmatic eruptions, hydrothermal degassing, and the sedimentary structures and record of these phenomena. The deployment of a multiparametric in-situ monitoring system at depth will allow us to track changes in the magma reservoir, and/or hydrothermal system in near real-time.
... Recently, the application of 40 Ar/ 39 Ar dating, combined with geochemical analysis of tephra from proximal volcanic succession and distal Middle Pleistocene sedimentary successions of this region, has increased significantly. Consequently, tephra can be confidently correlated to specific volcanic successions and sometimes to individual eruptive events of Italian volcanoes (Giaccio et al., 2013aInsinga et al., 2014;Marra et al., 2014;Petrosino et al., 2014a). Furthermore, Middle Pleistocene palaeoclimate records from various Apennine basins can be correlated using tephra as synchronous markers, regardless of the local climatic signals and of the accuracy of the related chronology. ...
... In the last 40 years, many studies on distal tephras from marine and lacustrine archives in the central Mediterranean (e.g. Keller et al., 1978;Paterne et al., 1988Paterne et al., , 2008Calanchi et al., 1998;Siani et al., 2004;Lowe et al., 2007;De Rosa et al., 2008;Bourne et al., 2010;Caron et al., 2010Caron et al., , 2012Sulpizio et al., 2010aSulpizio et al., , 2010bAlbert et al., 2012Albert et al., , 2013Insinga et al., 2014;Matthews et al., 2015;Donato et al., 2016), coupled with enhancements on proximal stratigraphy (e.g. Coltelli et al., 2000;Di Vito et al., 2008;Santacroce et al., 2008;Smith et al., 2011;Tomlinson et al., 2012Tomlinson et al., , 2015Albert et al., 2012Albert et al., , 2015Albert et al., , 2017, allowed improvements to be made in the reconstruction of ash dispersal from major explosive eruptions of Italian volcanoes. ...
New tephrostratigraphic data from three marine cores sampled in different depositional settings around southern Italy's coastline allowed correlating each of them with the regional tephrostratigraphy and to gain insights on ash dispersal from explosive eruptions of various intensities. Volume magnetic susceptibility curves, lithological analysis and geochemistry allowed the recognition of 38 tephras or cryptotephras in the three cores. The lithology of each tephra/cryptotephra was described, and the major element composition of volcanic glasses determined. Major element compositions of mineral phases and trace element compositions of bulk rock and volcanic glasses were also determined for selected samples. The majority of tephras/cryptotephras were correlated with the activity of Neapolitan volcanoes (16 from Somma-Vesuvius, 13 from Campi Flegrei, 1 from Ischia Island), whereas the others were correlated with deposits from to the volcanic activity of Lipari Island (6) and Mount Etna (1). The different tephras/cryptotephras were correlated to nine Plinian/Subplinian eruptions that occurred in the central Mediterranean region in the last 15,000 years. In addition, correlation with proximal counterparts highlighted the occurrence in marine core successions of several tephra layers related with moderately explosive eruptions from Neapolitan volcanoes that, in some cases, show dispersal areas comparable to those of Subplinian products. This finding means that the amount of fine-grained particles produced during explosive eruptions is independent with respect to the intensity of the eruption itself.
... Tephra SAOS2R-bottom can be correlated with the main marker tephra X-6 (108.9 ± 1.8 ka: Iorio et al. 2014) which occurs in terrestrial and marine archives of the Central Mediterranean area (Insinga et al. 2014 and references therein), and is characterized by an homogenous silica value (61-62 wt%) and distinctive K 2 O/Na 2 O value ranging from ≤1 to ≥2. ...
The southern Tyrrhenian continental margin is the product of Pliocene–Recent back-arc extension. An area of approximately 30 km ² of gentle (about 1.5°) lower slope of the last glacial outer shelf sedimentary wedge in water depths of between 200 and 300 m failed between 14 and 11 ka BP. We approached the landslide by multibeam and sub-bottom profiler surveying, high-resolution multichannel seismics, and coring for stratigraphic and geotechnical purposes. With regard to a slope-stability analysis, we carried out an assessment of the stratigraphic and structural setting of the area of the Licosa landslide. This analysis revealed that the landslide detached along a marker bed that was composed of the tephra layer Y-5 ( c. 39 ka). Several previously unknown geological characteristics of the area are likely to have affected the slope stability. These are the basal erosion of the slope in the Licosa Channel, a high sedimentation rate in the sedimentary wedge, earthquake shaking, the volcanic ash nature of the detachment surface, subsurface gas/fluid migration, and lateral porewater flow from the depocentre of wedge to the base of the slope along the high-permeability ash layers. A newly discovered prominent structural discontinuity is identified as the fault whose activity may have triggered the landslide.
... Glasses extracted from other tephra layers, handpicked within alluvial fan deposits, are much more weathered and difficult to analyse. Their composition is generally comparable with that of the tephras belonging to the Campanian Volcanic Zone of Rolandi et al. (2003), which have been already found both in deep-sea sediments of the Tyrrhenian and the Ionian Seas (Insinga et al., 2014), in some lacustrine sequences in the Southern Apennines (Munno and Petrosino, 2007), and in several outcrops in distal areas of the Campania Region (Marciano et al., 2008;Giaccio et al., 2012). One layer in particular, labelled S11 PAUP, displays a trachy-phonolitic composition with an Al 2 O 3 content higher than 19 wt% and has been tentatively associated with the preignimbritic tephra SEP 5 found in the Volturno Plain, whose age had been stratigraphically constrained between 105 and 130 ka (Santangelo et al., 2010). ...
The present study focuses on the morphotectonic evolution of the axial portion of the southern Apennine chain between the lower Calore River valley and the northern Camposauro mountain front (Campania Region). A multidisciplinary approach was used, including geomorphological, field‐geology, stratigraphical, morphotectonic, structural, ⁴⁰Ar/³⁹Ar and tephrostratigraphical data. Results indicate that from the Lower Pleistocene this sector of the chain was affected by extensional tectonics responsible for the onset of the sedimentation of Quaternary fluvial, alluvial fan and slope deposits. Fault systems are mainly composed of NW‐SE, NE‐SW and W‐E trending strike‐slip and normal faults, associated to NW‐SE and NE‐SW oriented extensions. Fault scarps, stratigraphical and structural data and morphotectonic indicators suggest that these faults affected the wide piedmont area of the northern Camposauro mountain front in the Lower Pleistocene ‐ Upper Pleistocene time span. Faults affected both the oldest Quaternary slope deposits (Laiano Synthem, Lower Pleistocene), and the overlying alluvial fan system deposits constrained between the late Middle Pleistocene and the Holocene. The latter are geomorphologically and chrono‐stratigraphically grouped into four generations, I generation: late Middle Pleistocene‐early Upper Pleistocene, with tephra layers ⁴⁰Ar/³⁹Ar dated to 158±6 and 113±7 ka; II generation: Upper Pleistocene, with tephra layers correlated to Campanian Ignimbrite (39 ka) and to the slightly older Campi Flegrei activity (⁴⁰Ar/³⁹Ar age 48±7 ka); III generation: late Upper Pleistocene‐early Holocene, with tephra layers correlated to the Neapolitan Yellow Tuff (15 ka); IV generation: Holocene in age. The evolution of the first three generations was controlled by Middle Pleistocene extensional tectonics, while Holocene fans do not show evidence of tectonic activity. Nevertheless, considering the moderate to high magnitude historical seismicity of the study area, we cannot rule out that some of the recognized faults may still be active.
... There are several eruptions which have been produced by Campanian volcanoes during this interval and which may overlap in composition with layer G, among which the Y-7, C-22, X-5 and X-6 are the most widespread (e.g. Bourne et al., 2010Bourne et al., , 2015Wulf et al., 2012;Giaccio et al., 2012Giaccio et al., , 2017aInsinga et al., 2014;Sulpizio et al., 2010;Tomlinson et al., 2015a,b;Leicher et al., 2016). However, when comparing altogether, the layer G appears unequivocally correlates to X-6, which in turn is clearly distinct by the other marker tephra (Fig. 5a). ...
The Grotta del Cavallo contains one of the most important stratification of Mousterian, Uluzzian and Final Epigravettian tecnocomplexes; its chronology is of paramount importance for understanding the timing of the transition between Middle and Upper Palaeolithic in the Mediterranean region as well as the demise of the Neanderthal and the dispersal of the first anatomically modern humans through Europe. Within the stratigraphy of the cave three different volcanic ash layers occur (layer G, Fa and C-II). They are located in the middle section of the Mousterian (layer G), in between the Mousterian and Uluzzian layers (layer Fa) and on top of the Uluzzian horizons (layer C-II). The three tephra layers were chemically fingerprinted and correlated to well-known and precisely dated widespread Late Pleistocene tephra markers. Specifically, layer G, Fa and C-II were correlated to the X-6 (108.7 ± 0.9 ka), Y-6 (45.5 ± 1.0 ka) and Campanian Ignimbrite (39.85 ± 0.14 ka), respectively. These findings provide robust chronological points allowing to conclude that: (i) the Mousterian occupation of the cave took place after the fall of the sea level following the MIS 5e high-stand; (ii) the Mousterian-Uluzzian boundary can be dated to 45.5 ± 1.0 ka and climatostratigraphically firmly placed at the transition between the Greenland Inter-stadial 12 (GI12)-Greenland Stadial 12 (GS12); (iii) the Uluzzian lasted for at least five millennial spanning the GS12-GI9 period and ended at beginning of the Heinrich Event 4.
... The abyssal plain is the deep basin located between the Mediterranean Ridge and Calabrian accretionary wedges, in the southern Ionian Sea. It is roughly defined by the 4000 m contour depth (IOC, 1981). The Ionian Abyssal Plain constitutes one of the forelands of the Mediterranean Ridge . ...
La paléosismologie sous-marine est une discipline basée sur la reconnaissance et l’étude des séismes passés à partir d’archives sous-marines tels que les dépôts turbiditiques. Cette discipline, mise en place à partir des années 1990 au niveau de la zone des Cascades (côte Nord-Ouest des Etats-Unis) a, par la suite, été développée dans d’autres mers, océans et lacs.La mer Ionienne est un petit bassin étroit et profond localisé au centre de la mer Méditerranée bordé par deux prismes d’accrétions, la ride Méditerranéenne à l’Est et le prisme Calabrais à l’Ouest. L’Est de la Sicile et la région Calabre ont été soumises à plusieurs reprises, à des séismes historiques destructeurs, parfois suivit de tsunamis, comme par exemple le séisme de 1693 AD à Catane (magnitude 7,4) ou celui de 1908 à Messine (de magnitude 7,1). Ce dernier séisme a déclenché des glissements sous-marins et des courants de turbidités qui sont à l’origine de rupture de câbles sous-marins. Au niveau de la plaine abyssale Ionienne, un autre type de dépôt est décrit à partir des données sismiques, caractérisées par une couche transparente. Ces méga-dépôts de plusieurs mètres d'épaisseur, sont associés à de grands évènements extrêmes (séismes, tsunamis, éruptions volcaniques) et sont appelés mégaturbidites ou homogénites.Les études réalisées durant cette thèse, se focalisent sur l’interprétation des turbidites et des méga-dépôts observés grâce à un nouveau jeu de données localisé dans la partie Ouest du prisme Calabrais et récolté durant la mission CIRCEE en octobre 2013. La compréhension des sources et des origines de ces dépôts est primordiale pour l’interprétation de l’enregistrement paléosismologique de la région. L’objectif général étant d'améliorer notre compréhension de la chronologie et l'origine des grands événements catastrophiques qui ont affecté la région.Ces nouvelles données, qui incluent des carottes sédimentaires, de la bathymétrie et des profils sismiques (Chirp et HR), ont permis dans un premier temps de revisiter l’interprétation des processus sédimentaires et l’origine des mégadépôts et en particulier, du dépôt le plus récent appelé « dépôt d’Augias ». Ce dernier, dont l’épaisseur atteint les douze mètres en plaine abyssale Ionienne, serait lié au séisme et tsunami de Crête en 365 AD. A partir de sa description sédimentologique et des diverses mesures réalisées, trois types de faciès ont été identifiés (faciès « mégaturbidite », « homogénite » et « turbidite sableuse épaisse ») et qui sont les résultats de différents processus sédimentaires. La deuxième partie de cette thèse représente une étude paléosismologique des derniers 25 ka en mer Ionienne basée sur des modèles d’âges. La période de temps recouverte par les carottes englobe la fin de la dernière période glaciaire, la remontée du niveau marin et la période historique. Cela a permis de différencier les dépôts de la période historique où l’évènement déclencheur principal des courants de turbidités est le séisme. Par contre pour les dépôts antérieurs il a pu être démontré que les variations eustatiques et climatiques ont un fort impact sur la fréquence de turbidites.
... Tephras are usually detected as glass shard concentrations within deep-sea sediments, where shards are not usually dissolved by weathering and where their original chemical properties are generally preserved. Therefore, marine tephrostratigraphy and cryptotephrostratigraphy have been established on the basis of glass shard chemistry (e.g., Westgate et al., 1998;Buhring and Sarnthein, 2000;Shane, 2000;Song et al., 2000;Shane et al., 2006;Aoki, 2008;Brendryen et al., 2010;Abbott et al., 2011;Lowe et al., 2012;Albert et al., 2012;Davies et al., 2012;Gorbarenko et al., 2014;Insinga et al., 2014;Satow et al., 2015). Tephras have also been used for linking deep-sea sediments with ice cores containing high-time-resolution records of d 18 O stratigraphy ( Davies et al., 2014), and they have been further applied to establish the chronologies of late Quaternary marine terrace deposits, which are deposits corresponding to past interglacial periods ( Koike and Machida, 2001;Machida and Arai, 2003;Matsu'ura et al., 2014a). ...
Using amphibole crystals, we detected tephras in deep-sea sequences (Chikyu C9001C cores) and correlated marine and terrestrial tephras in NE Japan; then we reconsidered some previously reported tephra ages by using the age model of the cores. We identified 50 spikes in amphibole grains (numbered A1-A50 from top to bottom). Among these, 12 spikes (A38-49) corresponded to a thick, non-tephric sand layer. We selected 20 spikes containing amphibole grains with glass coatings as likely primary tephras and analyzed their chemistry for tephra characterization. On the basis of its amphibole chemistry, we correlated spike A34 with the Tn-Cii-Ciii layers of the Tanabu-C tephra (Tn-C), which erupted from Osore volcano on Shimokita Peninsula. We then showed that spike A34 represents primary tephra deposition, not secondary deposition through bioturbation or bottom current reworking, because amphibole grains with homogeneous chemistry were accumulated only in sediment near the spike (within 10 cm). We also showed that the chemical variation within each amphibole grain was not as great as the variation between grains, which further supports the correlation between spike A34 and Tn-Cii-Ciii. These findings show that amphibole grains, which are resistant to weathering, can be used for characterization and correlation of weathered tephras from which glass shards have been removed by dissolution. The glass shard chemistry of the 16H6A 60-80 tephra at 4.58 m below spike A34 (which does not correspond to an amphibole spike) suggests that this tephra likely correlates with the amphibole-free Tn-Ci layer. In the terrestrial sequences, non-tephric sediments (marine sand and lahar deposits) occur between Tn-Ci and Tn-Cii-Ciii, suggesting that some time elapsed after the deposition of Tn-Ci before Tn-Cii-Ciii were deposited. By using the stratigraphic information of the 16H6A 60-80 tephra and spike A34 together with the δ¹⁸O stratigraphy of the deep-sea sequence, we re-assigned the eruptive age of Tn-C from the previously reported zircon fission-track age of 180 ± 40 ka to MIS 8 (257-263 ka).
... Here, we present a new 40 Ar/ 39 Ar age for tephra POP4, which chemically matches the X-6 tephra (Regattieri et al., 2015) of the marine tephrostratigraphic schemes of Keller et al. (1978). This tephra shows a large dispersal area covering the central Mediterranean and the Balkans (Bourne et al., 2015;Donato et al., 2016, Insinga et al., 2014, Iorio et al., 2014Leicher et al., 2016;Lézine et al., 2010;Petrosino et al., 2016;Sulpizio et al., 2010;Vogel et al., 2010). ...
Here we present a multiproxy record (δ13C, δ18O, major and minor element composition, mineralogy, and low-resolution biogenic silica content) from a lacustrine succession in the Sulmona Basin, central Italy. Based on previous tephrochronological constraints and a new 40Ar/39Ar dating of a tephra matching the widespread X-6 tephra, the record spans the ca. 129–92 ka period and documents at sub-orbital scale the climatic and environmental changes over the Last Interglacial and its transition to the Last Glacial period. The δ18O composition is interpreted as a proxy for the amount and seasonality of local precipitation, whereas variations in elemental and mineralogical composition are inferred to reflect climatic-driven changes in clastic sediment input. The observed variations are consistent among the different proxies, and indicate that periods of reduced precipitation were marked by enhanced catchment erosion, probably due to a reduction in vegetation cover. The first part of the Last Interglacial shows the most negative δ18O values. Comparison with pollen records from the Mediterranean suggests a greater seasonality of the precipitation at this time. At millennial-to-centennial time scales, comparison of the Sulmona record with speleothem δ18O records from central Italy highlights a highly coherent pattern of hydrological evolution, with enhanced variability and similar events of reduced precipitation consistently recorded by each isotope record. The observed intra-interglacial variability can potentially be linked, within the uncertainties associated with each age model, to similar variations observed in sea-surface temperature records from the Mediterranean and the North Atlantic, suggesting a link between Mediterranean hydrology and North Atlantic temperature and circulation patterns that persists during periods of low ice volume.
This chapter presents approaches to understanding the eruptive history of a volcano, both in the near and distant past, in order to establish scenarios for future eruptions and a monitoring strategy. It shows how improving the knowledge of eruption history, eruption types and timescales is fundamental to improve the prediction and management of eruptions in the short and long term. The chapter emphasizes the importance of hazard mapping derived from the work of Crandell and Mullineaux at Mount St. Helens, and inferred from their work on the eruptive history of that volcano. The time factor is a key element in the behavior of a volcano. The chapter highlights three prominent figures who have each marked the history of volcanology: Professor Alfred Lacroix, the naturalist Jean‐Baptiste Bory de Saint‐Vincent and the ambassador William Hamilton. The use of old maps provides a lot of information on the transformations that volcanoes have undergone over time.
Explosive activity preceding the ~40 ka Campanian Ignimbrite (CI) eruption in the Neapolitan volcanic area, Southern Italy, has long been speculated based on the occurrences of widespread tephra layers, with a Campanian geochemical signature, such as the C-22, X-5, and X-6, preserved in Mediterranean Marine Isotope Stage (MIS) 5 sedimentary records. However, previous studies of pre-CI pyroclastic units occurring in close proximity of the Neapolitan volcanoes, including Campi Flegrei, Somma-Vesuvius, Ischia and Procida islands, did not allow a conclusive identification of the near-source equivalents of these tephra markers. Here we present a comprehensive characterization of four pyroclastic units from the Campanian Plain, comprising major and trace element glass compositions, Srsingle bondNd isotopes and 40Ar/39Ar dating. Our data allowed the identification of the medial equivalents of the MIS 5 tephra markers, including the widespread C-22, X-5, and X-6 tephra, and their assignment to previously undocumented Campi Flegrei activity between 109 and 92 ka. In addition to substantially extending Campi Flegrei explosive activity deeper in time, and thus providing the basis for a revaluation of its history, our findings provide new precise radioisotopic dating to better constrain the chronology of the millennial scale climatic oscillations of the MIS 5c-d in the Mediterranean area and possibly on a larger scale.
This chapter reviews the current state of knowledge on the volcanic and deformation history of the Campi Flegrei caldera. This caldera, a nested and resurgent collapse structure in a current state of unrest, is the world’s best example of a restless volcano in a densely populated area. It formed through two major collapses related to the Campanian Ignimbrite (~39 ka) and the Neapolitan Yellow Tuff (~15 ka) eruptions. Each caldera collapse mostly occurred through activation of portions of northeast-southwest and northwest-southeast regional faults. The younger caldera is the currently active portion of the entire structure and has been the site of intense volcanism and an ongoing deformation. This volcanism produced not less than 70 eruptions, largely explosive with very few effusive events, concentrated in three clusters of activity, called epochs, and separated by two periods of quiescence during which two widespread paleosols formed. During each epoch, the eruptions occurred at mean time intervals of tens of years. The last event produced the Monte Nuovo tuff cone in AD 1538, after ~3,000 years of quiescence. Deformation mostly consists of a resurgence process that has generated a net uplift of about 90 m mainly through portions of regional faults probably active also during caldera collapses. Within this process, a deformation lasting since the caldera collapse called “long-term deformation” and one that takes place over years or decades called “short-term deformation” can be distinguished. Vent locations through time provide a good tracer of the long-term deformation. The vents of both epochs 1 and 2 were located along the structural boundary of the Neapolitan Yellow Tuff caldera, while those of epoch 3 were mostly concentrated in the north-eastern sector of the resurgent portion of the caldera floor. Short-term ground deformation episodes, also known as bradyseism, are transient events within the long-term resurgence process and can be reconstructed over the past 2,000 years. In particular, levelling data available since 1905 highlight a general subsidence interrupted by three major and many minor uplifts, with the ongoing one beginning in late 2004. Some geological and volcanological aspects of the Campi Flegrei caldera are still under debate within the scientific community. One of these aspects concerns the Campanian Ignimbrite eruption and related caldera collapse, namely the relations among architecture of the magmatic feeding system, timing and dynamics of the eruption, type (central, fissure) and areal distribution of the eruption vents, and volume of caldera collapse versus volume of erupted magma. A very preliminary hypothesis aimed at providing a still missing unifying explanation for all the mentioned aspects of the Campanian Ignimbrite eruption is proposed. This hypothesis argues that the eruption was fed by vents located on a network of regional faults that controlled the collapse of a caldera in the Neapolitan-Phlegraean area. Further crucial scientific points that need to be addressed in order to increase our knowledge of the volcano are summarised in conclusions.
A tephrochronological investigation was carried out at site ND14Q (1013 m of water depth), located in the southern Adriatic Sea, offshore the Gargano promontory. It was drilled in the frame of The NextData Project (www.nextdataproject.it), focused on paleoclimate research. To obtain a composite and well preserved deep marine record, three cores were raised at the study site. Twelve primary cryptotephra and one tephra were analysed in terms of major-element content and correlated with a total of sixteen eruptive events. The studied materials display K-alkaline and subalkaline features pointing to a correlation with the Somma-Vesuvius, Campi Flegrei and Lipari Island (Aeolian Arc) volcanic activity occurred during the Late Pleistocene-Holocene. In detail, major marker tephra of the central Mediterranean have been recognized, among which the phlegraean Neapolitan Yellow Tuff (ca. 15 ka), Pomici Principali (ca. 12 ka BP) and Astroni-Agnano-Monte Spina (ca. 4.2 ka - 4.4 ka BP) eruptions and, for the first time in this area, the Vesuvian 79 CE event. The very well preserved Mercato (ca. 9 ka BP) and Fiumebianco-Gabellotto (ca. 8.4 ka BP) cryptotephra have also been found in the sapropel S1 interval of the succession, which definitely records the last ca. 22 kyr (Pomici di Base tephra). A number of other Plinian and sub-Plinian events also occur and the availability of multiple cores provided new insights into their temporal relation such as between AP2 and Astroni 6 eruptions. The identification of tephra sourced by well-dated volcanic events, along with several AMS ¹⁴C age results, allowed an accurate chronological framework for the composite tephrostratigraphic record, thus providing accurate ages for those deposits with an uncertain correlative event. In addition, stratigraphic evidences in the core replicates at ND14Q site showed that several intervening factors affect preservation and traceability of cryptotephra deposits in the marine realm posing main critical issues on volcanological and paleoclimate research.
Direct correlations between terrestrial and marine climate-proxy records are essential in order to determine potential lead/lag relationships in the response of the terrestrial and marine realms to climate forcing. In the Eastern Mediterranean region, such land-sea correlations have not yet been established beyond c. 200 ka. To explore the potential of tephra layers for Late and Middle Pleistocene land-sea correlations in the Eastern Mediterranean region, we have revisited yet unconfirmed tephra layers previously reported from Ocean Drilling Program (ODP) Site 964 (Ionian Basin) for the past c. 800 kyr in order to identify their origin and examine potential terrestrial counterparts. Using major-and trace-element glass analyses, we confirmed the presence of seven visible tephra layers with ages from 623 to 38 ka. These tephra layers represent known tephra isochrons from Italian volcanic centers (Y-5, Y-7, X-6, and V-0) and three yet unknown eruptions from Etna (623 ka), the Campanian Volcanic Zone (CVZ; 238 ka), and Pantelleria (238 ka). Because the majority of the previously reported tephra layers from ODP Site 964 were identified as clastic layers of non-volcanic origin, cryptotephra analyses were carried out for cores spanning Marine Isotope Stages (MIS) 13 to 9 (500–320 ka). This effort yielded 19 cryptotephra layers originating from Santorini volcano, the CVZ, possibly Roccamonfina volcano, and an undefined source in either the Aeolian Islands or the South Aegean Volcanic Arc. Two tephra layers are correlated with potential equivalents from terrestrial archives on the Italian and Balkan Peninsulas, including tephra isochrons SC5/A7/OH-DP-1966 (c. 493 ka; Mercure basin, Acerno basin, and Lake Ohrid) and TP09-65.95 (c. 359 ka; Tenaghi Philippon) that represent an unknown eruption of Roccamonfina and the Cape Therma 1 eruption of Santorini, respectively. Direct linking of the marine record from ODP Site 964 with the terrestrial records from Tenaghi Philippon, Lake Ohrid, and the Acerno basin via tephra tie points allowed us to circumvent shortcomings of the individual age models, and to obtain a comprehensive picture of climate variability in the greater Eastern Mediterranean region for the MIS 13–9 interval.
The Brown Tuffs (BT) are widespread reddish-brown to grey, ash-rich pyroclastic deposits recognized in the stratigraphic sequences of the Aeolian Islands and Capo Millazzo peninsula (Sicily) that span the last 80 ky. They have very homogeneous lithological, textural and sedimentological features which make it difficult to reliably correlate units on the islands to proximal units in the source areas. Here we carefully re-interpret the stratigraphic profiles of the BT on Vulcano and Lipari where the deposits are thickest and present the most complete succession. The investigation is based on a large dataset of major and minor element geochemistry of juvenile glass components for the majority of the recognized BT depositional units, whilst also providing new radiocarbon ages. The distinctive chemical groupings observed within the glass analyses, both temporally and spatially, allow us to fingerprint the three main stratigraphically defined macro-units in which the BT succession can be sub-divided using prominent tephra marker beds, the Ischia Tephra (Monte Epomeo Green Tuff; 56 ky) and Monte Guardia pyroclastics from Lipari (herein radiocarbon dated to 27–26 ky). The Lower (80–56 ky; LBT), Intermediate (56–27 ky; IBT) and Upper BT (here dated at 24–6 ky; UBT) macro-units display K-series volcanic glasses ranging from basaltic trachy-andesites, through trachy-andesites, to more evolved trachytes, all consistent with an origin on Vulcano. The UBT are clearly distinguished from the lower macro units by their higher-SiO2 trachy-andesite to trachytic glasses, which extend to noticeably lower TiO2, CaO and MgO contents. These features make it possible to re-define the geochemical-evolutionary boundary between IBT and UBT as corresponding to the 24 ky Spiaggia Lunga scoria bed on Vulcano, which is stratigraphically higher (and younger) than the previous boundary marker (Monte Guardia). The glass compositions of the LBT, IBT and UBT are used to: (1) assess links to known proximal eruption units outcropping on Vulcano; (2) validate medial-distal BT occurrences across the Aeolian archipelago (Salina, Filicudi and Panarea) and on Capo Millazzo; (3) confirm that the BT are responsible for distal volcanic ash layers preserved in Central Mediterranean marine sedimentary archives. Interestingly, the glass compositions of the UBT are very similar to those of the Punte Nere unit, the earliest pyroclastic products erupted from the currently active La Fossa cone on Vulcano, indicating the corresponding magmatic system has likely erupted similar melts and products over the last 24 ky and thus extending its life cycle. Such information is crucial for evaluating the long-term eruption scenarios underpinning hazard assessment of the La Fossa caldera magmatic system.
The Oscurusciuto rock shelter (southern Italy) is crucial for the understanding of Neanderthals’ subsistence and settlement strategies as it contains a ~ 6-m-thick reliable deposit made up of several Middle Palaeolithic levels. This paper focuses on level SU 14, a 60-cm-thick deposit of volcanic tephra containing traces of human occupation only in the few upper centimetres.
Geochemical and mineralogical features of SU 14 deposits allowed their correlation to the ‘Mount Epomeo Green Tuff’ eruption, which came from Ischia volcano and dated to ~ 55,000 years bp. The pyroclastic materials injected into the atmosphere caused an ash fall-out over a large part of southern Italy, resulting in the alteration of ecosystems.
Sedimentological data demonstrate that the formation of SU 14 is attributable to a short-term event. Moreover, the lithic behaviour indicates that Neanderthals used the shelter mainly to perform specific activities related to the first phases of the reduction sequence (i.e. selection and import of pebbles into the site, initialisation and production of the first generation of debitage objectives, and introduction of already finished tools). Consequently, the layer SU 14 raises questions regarding the impact of deposition of volcanic ash on human communities, offering the opportunity to investigate the settlement and technological choices made by Neanderthals who were constrained by such an adverse environmental event.
Very high-resolution, single channel (IKB-Seistec™) reflection profiles acquired offshore the Napoli Bay, complemented with geological and geophysical data from the literature, provide unprecedented, superb seismic imaging of the Latest Pleistocene-Holocene stratigraphic architecture of the submerged sectors Campi Flegrei and Somma-Vesuvius volcanic districts. Seismic profiles were calibrated by gravity core data and document a range of depositional systems, volcanic structures and hydrothermal features that evolved after the onset of the Last Glacial Maximum (ca. 18 ka BP) over the continental shelf on the Campania coastal zone.Seistec profiles from the Pozzuoli Bay yield high-resolution images of the shallow structure of the collapse caldera-ring fault - resurgent dome system associated with the eruption of the Neapolitan Yellow Tuff (NYT) (ca 15 ka BP) and support a working hypothesis to assess the timing and the styles of deformation of the NYT resurgent structure throughout the Latest Quaternary. Seismic images also revealed the nature of the fragile deformation of strata along the NYT ring fault system and the occurrence of hydrothermal fluids and volcanic/sub-volcanic intrusions ascending along the ring fault zone. Seismic data acquired over the continental shelf off the Somma-Vesuvius stratovolcano, display evidence of gravitational instability of sand wave deposits originated by the underwater modification of pyroclastic flows that entered the seawater after destroying the Roman city of Herculaneum during the 79 CE eruption of Vesuvius.At the Banco della Montagna, a hummocky seafloor knoll located between the Somma-Vesuvius and the Pozzuoli Bay, seismic profiles and gravity core data revealed the occurrence of a field of volcaniclastic diapirs formed by the dragging and rising up of unconsolidated pumice, as a consequence of fluid overpressure at depth associated with active degassing and fluid venting at the seafloor.
In the Ionian Sea, the subduction of the Nubia plate underneath the Eurasia plate leads to an important sediment remobilisation on the Calabrian Arc and the Mediterranean Ridge. These events are often associated with earthquakes and tsunamis. In this study, we analyse gravity-driven deposits in order to establish their recurrence time on the Calabrian Arc and the western Mediterranean Ridge. Four gravity cores collected on ridges and slope basins of accretionary prisms record turbidites, megaturbidites, slumping and micro-faults over the last 330,000 years. These turbidites were dated by correlation with a hemipelagic core with a multi-proxy approach: radiometric dating, δ18O, b* colour curve, sapropels and tephrochronology. The origin of the gravity-driven deposits was studied with a sedimentary approach: grain-size, lithology, thin section, geochemistry of volcanic glass. The results suggest three periods of presence/absence of gravity-driven deposits: a first on the western lobe of the Calabrian Arc between 330 000 and 250 000 years, a second between 120 000 years and present day on the eastern lobe of the Calabrian Arc and over the last 60 000 years on the western lobe, and a third on the Mediterranean Ridge over the last 37 000 years. Return times for gravity-driven deposits are around 1000 years during the most important record periods. The turbidite activity also highlights the presence of volcaniclastic turbidites that seems to be link to the Etna changing morphology over the last 320 000 years.
A main volcanic marker has been identified for the first time on the continental shelf of the northernPhlegraean Fields in the Gulf of Gaeta (Campania region, eastern Tyrrhenian margin, Italy) bymeans of Subbottom Chirp profile grid and stratigraphic analysis of a core collected on the slope. Inthe seismic sections, the core bottom corresponds to the top of a continuous and parallel reflector(V) interbedded within the transgressive deposits of the Late Quaternary-Holocene depositionalsequence. The Transgressive System Tract deposits are particularly thick compared to the majorityof the transgressive deposits of other shelf settings. This might be due to the input of pyroclasticand volcaniclastic deposits related to the intense eruptive activity of the Campania Plain during theLate Pleistocene-Holocene time span. Undulations and pockmarks are the main morphologicalfeatures of the sea floor and they might be linked to gas uprising, widely detected in the study area.The V reflector is located on the shelf from northeast to southwest at different depths, ranging from10 ms (about 8 m) to 30 ms (about 25 m) below sea floor and it can be mapped down to thecontinental slope. The tephrostratigraphic analysis of this continuous reflector allowed to correlateit with the Neapolitan Yellow Tuff deposits emplaced at Phlegraean Fields at ca. 15 ka
Marked changes in human dispersal and development during the Middle to Upper Paleolithic transition have been attributed to massive volcanic eruption and/or severe climatic deterioration. We test this concept using new records of volcanic ash layers of the Campanian Ignimbrite (CI) eruption, dated to c. 40,000 years ago (40 ka BP). The distribution of the CI has been enhanced by the discovery of ‘cryptotephra’ deposits, volcanic ash layers that are not visible to the naked eye, in archaeological cave sequences. They enable us to synchronise archaeological and paleoclimatic records through the period of transition from Neanderthal to earliest anatomically modern human populations in Europe. Our results confirm that the combined effects of a major volcanic eruption and severe climatic cooling failed to have lasting impacts on Neanderthals or early modern humans in Europe. We infer that modern humans proved a greater competitive threat to indigenous populations than natural disasters.
SUMMARY: Trace-element data for mid-ocean ridge basalts (MORBs) and ocean island basalts (OIB) are used to formulate chemical systematics for oceanic basalts. The data suggest that the order of trace-element incompatibility in oceanic basalts is Cs ≈ Rb ≈ (≈Tl) ≈ Ba(≈ W) > Th > U ≈ Nb = Ta ≈ K > La > Ce ≈ Pb > Pr (≈ Mo) ≈ Sr > P ≈ Nd (> F) > Zr = Hf ≈ Sm > Eu ≈ Sn (≈ Sb) ≈ Ti > Dy ≈ (Li) > Ho = Y > Yb. This rule works in general and suggests that the overall fractionation processes operating during magma generation and evolution are relatively simple, involving no significant change in the environment of formation for MORBs and OIBs.
In detail, minor differences in element ratios correlate with the isotopic characteristics of different types of OIB components (HIMU, EM, MORB). These systematics are interpreted in terms of partial-melting conditions, variations in residual mineralogy, involvement of subducted sediment, recycling of oceanic lithosphere and processes within the low velocity zone. Niobium data indicate that the mantle sources of MORB and OIB are not exact complementary reservoirs to the continental crust. Subduction of oceanic crust or separation of refractory eclogite material from the former oceanic crust into the lower mantle appears to be required. The negative europium anomalies observed in some EM-type OIBs and the systematics of their key element ratios suggest the addition of a small amount (≤1% or less) of subducted sediment to their mantle sources. However, a general lack of a crustal signature in OIBs indicates that sediment recycling has not been an important process in the convecting mantle, at least not in more recent times (≤2 Ga). Upward migration of silica-undersaturated melts from the low velocity zone can generate an enriched reservoir in the continental and oceanic lithospheric mantle. We propose that the HIMU type (eg St Helena) OIB component can be generated in this way. This enriched mantle can be re-introduced into the convective mantle by thermal erosion of the continental lithosphere and by
The new geological map of Etna volcano at 1:50,000 scale represents a significant progress in the geological studies of this volcano over the last 30 years, coming after Waltershausen's map published around the mid of 19(th) century, the first geological map of a large active volcano, and the ROMANO et alii (1979) map published about a century later, both at 1:50,000 scale. Lithostratigraphy was used for mapping volcanic units and then Unconformity Bounded Units were applied to group lithostratigraphic units into synthems. In addition, lithosomes were exploited to better represent the spatial localization of different eruptive centres according to their morphology. On the whole, we identified 27 lithostratigraphic units, grouped into 8 synthems, and 9 volcanoes. In detail, effusive and explosive deposits generated by each eruption of Mongibello and, partially, Ellittico volcanoes were mapped as flow rank. This stratigraphic framework represents the best synthesis of the geological evolution of Etna volcano using the main unconformities recognized within its complex volcanic succession. In addition, we constrain the Etna volcanic succession and its lithostratigraphic units chronologically by radioisotope age determinations. On the basis of the outlined synthemic units, it was possible to divide Etna's volcanic succession into 4 supersynthems, which correspond to 4 well-defined and spatially localized phases. The detailed reconstruction of the past eruptive activity allowed compiling the most accurate dataset in particular of the Holocene eruptions of Etna volcano, which will enable significantly improving the volcanic hazard assessment, together with petrological interpretation of erupted magmas and geophysical modelling of the volcano plumbing system.
Since the 1970's, about 50 radio-isotopic ages have been determined on Etna volcanics using different techniques: Th-U and K/Ar. Unfortunately, these ages cannot be readily used to constrain the new stratigraphic setting of the volcano, because of the uncertainty in sample locations or, sometimes, the large errors affecting the calculated ages. For this reason a program of radio-isotopic dating applying the Ar-40/Ar-39 incremental heating technique to date the groundmass of basaltic samples has been carried out from 2002. Forty samples (22 of which are of new publication) were collected from key outcrops on Etna volcano, selected on the basis of their stratigraphic position, while one sample was collected from the Hyblean plateau volcanics. We have obtained reliable results from all volcanics analysed from 542 ka up to 10 ka with the MSWD's (Mean Square of Weighted Deviates) ranging from 0.03 up to 1.7 excluding IS sample (MSWD = 6.28). These new results allow us to: i) assign an age to 19 of the 25 lithostratigraphic units defined in the new geological map of Etna volcano; ii) clarify the uncertain stratigraphic position of isolated volcanic units; iii) constraint the temporal hiatus that matches the main unconformities; iv) outline the lapse of time between the end of the Hyblean volcanism and the beginning of eruptive activity in the Etna region.
The main purpose of the paper is the reconstruction of the paleoclimatic record of the longest (37.04 m) deep-sea core so far recorded in the eastern Mediterranea sea. Core KC01B was raised from the Calabrian Ridge in the framework of the European MAST-Marflux Project. Quantitative calcium carbonate, grain size, planktonic foraminifer and calcareous nannofossil investigations were carried out on 337 samples (about 1 sample/10 cm) taken throughout the core (with the exception of the disturbed 231 uppermost cm). The core bottom has been dated at about 1100 ka, on the basis of the recognition of the Jaramillo magnetic event and the small Gephyrocapsa nannofossil Zone. The upward decreasing calcium carbonate content and average grain size, combined with the upward increasing sedimentation rate, witness the much higher clay mineral supply characterizing the upper 10-12 m of the core. The study of planktonic foraminifer assemblages allowed the reconstruction of climatic fluctuations which affected the Mediterranean area during early to late Pleistocene times. In the upper part of the core, the well known climatic stages recorded in several other Mediterranean core have been clearly recognized. Below about 22.7 m from core top, corresponding to climatic stage 14, the short term trend of the climatic curve changes from lower to higher frequency climatic cycles. At the same level, the long term trend of the curve leads from a mean value of -15.3 (above 22.7 m) to +3.3 (below that level). Correlation of sapropel layers with respect to the climatic curve allowed to recognize the presence of sapropels S11 and S12, to demonstrate the lack of sapropel S10 and to correlate three pre-S12 sapropel layers with relatively cold climatic intervals. The study of calcareous nannofossils resulted in the following calibrations: the top of the small Gephyrocapsa Zone with the first warm fluctuations following the top of the Jaramillo magnetic event; the LAD of Gephyrocapsa sp. 3 with climatic stage 15; the LAD of P. lacunosa with the higher part of climatic stage 13; an abundance increase of small with respect to medium sized Gephyrocapsa with climatic stage 8; the base of the E. huxleyi Acme Zone with the boundary between climatic stages 4 and 3.
A signifi cant uncertainty exists in the definition of both surface pattern and subsurface continuity (i.e., coupling vs. decoupling) of active normal faults in the Apennines. In this study, we investigated the epicentral area of the MS = 6.9, 1980 Irpinia earthquake —one of the most destructive historical earthquakes in Italy—based on detailed topography analyses, morphostratigraphic and structural data, and new age constraints from Quaternary deposits. The active tectonic behavior of the study area is controlled by a series of subparallel, mainly WNW-ESE– to NW-SE–trending, dominantly extensional faults spanning over the southern Apennines axial belt. A large part of the active fault strands is characterized by a subdued topographic expression, as a result of the young age of extensional faulting initiation, and of relatively low mean slip rates. In addition, as already known from long historical seismicity records elsewhere, long-lasting quiescence might alternate with clusters of closely spaced, strong earthquakes. The long-term morphostratigraphic record confi rms that long-lasting quiescence may punctuate fault activity, with major implications for seismic hazard assessment. The relatively smallsized cumulative fault throws estimated by surface evidence contrast with subsurface information provided by crustal-scale cross sections and seismological evidence, which both suggest the occurrence at depth of large displacement, mature fault zones capable of nucleating large earthquakes. Furthermore, although the surface distribution of active fault strands overlaps the belt affected by present-day low-magnitude seismicity and by large historical earthquakes, a mismatch in the attitude and kinematics of shallow versus deep faults is unraveled by a comparison of surface geological versus seismological data sets. This feature suggests a decoupling between surface and deep fault zones, and that outcropping fault planes cannot always be straightforwardly traced down to hypocentral depths, particularly in fold-andthrust belts characterized by strong rheological contrasts. On the other hand, stress inversion from outcropping active faults and from earthquake focal mechanisms indicates a general consistency of the stress fi eld, thus suggesting that a homogeneous late Quaternary extensional regime produces complex reactivation of the inherited, articulated fault network affecting different structural levels of the southern Apennines.
We measured apparent marine radiocarbon ages for the Mediterranean Sea, Black Sea, and Red Sea by accelerator mass spectrometry radiocarbon analyses of 26 modern, pre-bomb mollusk shells collected living between AD 1837 and 1950. The marine reservoir (R(t)) ages were estimated at some 390 ± 85 yr BP, 415 ± 90 yr BP and 440 ± 40 yr BP, respectively. R(t) ages in the Mediterranean Sea and Black Sea are comparable to those for the North Atlantic Ocean (<65°N), in accordance with the modern oceanic circulation pattern. The DR values of about 35 ± 70 yr and 75 ± 60 yr in the Mediterranean area show that the global box-diffusion carbon model, used to calculate R(t) ages, reproduces the measured marine 14C R(t) ages in these oceanic areas. Nevertheless, high values of standard deviations, larger than measurement uncertainties are obtained and express decadal R(t) changes. Such large standard deviations are indeed related to a decrease of the apparent marine ages of some 220 yr from 1900 AD to 1930 AD in both the Mediterranean Sea and the western North Atlantic Ocean.
The identification and characterisation of high-frequency climatic changes during the Holocene requires natural archives with precise and accurate chronological control, which is usually difficult to achieve using only 14C chronologies. The presence of time-spaced tephra beds in Quaternary Mediterranean successions represents an additional, independent tool for dating and correlating different sedimentary archives. These tephra layers are potentially useful for resolving long-standing issues in paleoclimatology and can help towards correlating terrestrial and marine paleoclimate archives. Known major tephras of regional extent derive from central and southern Italy, the Hellenic Arc, and from Anatolia. A striking feature of major Holocene tephra deposition events in the Mediterranean is that they are clustered rather than randomly distributed in time. Several tephra layers occurred at the time of the S1 sapropel formation between c. 8.4 and 9.0 ka BP (Mercato, Gabellotto-Fiumebianco/E1, Cappadocia) and other important tephra layers (Avellino, Agnano Monte Spina, ‘Khabur’ and Santorini/Thera) occurred during the second and third millennia BC, marking an important and complex phase of environmental changes during the mid- to late-Holocene climatic transition. There is great potential in using cryptotephra to overlap geographically Italian volcanic ashes with those originating from the Aegean and Anatolia, in order to connect regional tephrochronologies between the central and eastern Mediterranean.
A high-resolution integrated stratigraphy is presented for the Late Quaternary in the southern-eastern Tyrrhenian Sea. It is based on calcareous plankton taxa (planktonic foraminifera and nannoplankton) distribution, δ¹⁸OGlobigerinoidesruber record, tephrostratigraphy and radiometric dating methods (²¹⁰Pb and ¹³⁷Cs, AMS ¹⁴C) for a composite sediment core (from the top to the bottom, C90-1m, C90 and C836) from the continental shelf of the Salerno Gulf. High sedimentation rates from ca 1 cm/100 y for the early Holocene, to 3.45 cm/100 y for the middle Holocene to 8.78 cm/100 y from late Holocene and to 20 cm/100 y for the last 600 AD, make this area an ideal marine archive of secular paleoclimate changes. Quantitative distributional trend in planktonic foraminifera identify seven known (1F–7F) eco-biozones, and several auxiliary bioevents of high potential for Mediterranean biostratigraphic correlation. Recognised were: the acme distribution of Neogloboquadrina pachyderma r.c. between 10.800 ± 0.400 ka BP and 5.500 ± 0.347 ka BP, a strong increase in abundance of Globorotalia truncatulinoides r.c. and l.c. at 5.500 ± 0.347 ka BP and at 4.571 ± 0.96 ka BP, respectively, an acme interval of Globigerinoides quadrilobatus (between 3.702 ± 0.048 ka BP and 2.70 ± 0.048 ka BP) and the acme/paracme intervals of T. quinqueloba (acme between 3.350 ± 0.054 ka BP and 1.492 ± 0.016 ka BP; paracme between 1.492 ± 0.016 ka BP and 0.657 ± 0.025 ka BP; acme beginning 0.657 ± 0.025 ka BP).
A detailed tephrostratigraphic study supported by stable isotope (δ18O) analyses and AMS 14C dating was carried out on a high sedimentation rate deep-sea core recovered in the northern Ionian Sea. Eight tephra layers were recognised, all originated from explosive eruptions of southern Italian volcanoes. These tephra layers are correlated with terrestrial proximal counterparts and with both marine and lacustrine tephra already known in the central Mediterranean area. The oldest tephra (dated at ca. 19.4 ka cal BP) is tentatively correlated to the Monte Guardia eruption from Lipari Island. Two other rhyolitic tephra layers were correlated with the explosive volcanic activity of Lipari Island: Gabellotto-Fiumebianco/E-1 (8.3 ka cal BP) located close to the interruption of Sapropel S1 deposit, and Monte Pilato (ca. AD 1335) in the uppermost part of the core. The Na-phonolitic composition of the other five recognised tephra layers indicates the Somma-Vesuvius as the source. The composition is quite homogeneous among the five tephra layers, and fits that of the Mercato proximal deposits. Beyond the striking chemical similarity with the Mercato eruption, these tephra layers span over ca. 2000 years, preventing correlation with the single well known Plinian eruption of the Somma-Vesuvius. Therefore, at least two of these tephra layers were assigned to an interplinian activity of the Somma-Vesuvius between the eruptions of Mercato and Avellino, even though these eruptions remains poorly constrained in the proximal area. By contrast, the most prominent tephra layer (2 mm white tephra visible at naked eyes) was found within the S1a Sapropel interval. Despite the possible complication for the presence of similar eruption with different ages we argue that Mercato is probably a very good marker for the onset of sapropelic condition in the Ionian Sea and can be used for land-sea correlations for this important climatic event. More in general, these data allow a significant update of the knowledge of the volcanic ash dispersal from Lipari and Somma-Vesuvius volcanoes.
At Pantelleria, peralkaline silicic magmas were erupted across a range of eruptive typologies and magnitudes: pyroclastic flows, Plinian to strombolian pumice fallout and lava flows. In this paper we focus on the intermediate cycle of eruptive activity which is bracketed by ignimbrite units slightly older than the two caldera collapses which marked the volcanological activity of the island. This age interval (180–85 ka) was punctuated by six ignimbrite-forming eruptions (silicic and variably peralkaline) for a cumulative erupted magma volume of approximately 6 km3 dense rock equivalent. Based on new 40Ar/39Ar (Na,K)-feldspar ages and petrographic data, we propose an updated volcanostratigraphic scheme for these welded and rheomorphic ignimbrites that can be summarised as follows: (i) the age of the old (‘La Vecchia’) caldera collapse is now tightly constrained between 140 and 146 ka and the caldera-forming eruption can be traced to a lithic-rich welded tuff breccia that outcrops in two opposite sectors of the island (south-west and north-east); (ii) four ignimbrite units previously considered unrelated are now merged in two distinct eruptive paroxysmal events at 107 and 85 ka. In particular, the 85 ka eruptive event is comparable in magnitude to the younger (caldera forming) Green Tuff Plinian eruption; (iii) the recurrence patterns of the 107 and 85 ka eruptions, compared to the Green Tuff, allow us to qualitatively assess that the climax in production of low-temperature silicic and peralkaline melt was focused in the age interval 85–45 ka.
The central-western Mediterranean area is a key region for understanding the complex interaction between igneous activity and tectonics. In this review, the specific geochemical character of several ‘subduction-related’ Cenozoic igneous provinces are described with a view to identifying the processes responsible for the modifications of their sources. Different petrogenetic models are reviewed in the light of competing geological and geodynamic scenarios proposed in the literature.Plutonic rocks occur almost exclusively in the Eocene–Oligocene Periadriatic Province of the Alps while relatively minor plutonic bodies (mostly Miocene in age) crop out in N Morocco, S Spain and N Algeria. Igneous activity is otherwise confined to lava flows and dykes accompanied by relatively greater volumes of pyroclastic (often ignimbritic) products. Overall, the igneous activity spanned a wide temporal range, from middle Eocene (such as the Periadriatic Province) to the present (as in the Neapolitan of southern Italy). The magmatic products are mostly SiO2-oversaturated, showing calcalkaline to high-K calcalcaline affinity, except in some areas (as in peninsular Italy) where potassic to ultrapotassic compositions prevail. The ultrapotassic magmas (which include leucitites to leucite-phonolites) are dominantly SiO2-undersaturated, although rare, SiO2-saturated (i.e., leucite-free lamproites) appear over much of this region, examples being in the Betics (southeast Spain), the northwest Alps, northeast Corsica (France), Tuscany (northwest Italy), southeast Tyrrhenian Sea (Cornacya Seamount) and possibly in the Tell region (northeast Algeria).Excepted for the Alpine case, subduction-related igneous activity is strictly linked to the formation of the Mediterranean Sea. This Sea, at least in its central and western sectors, is made up of several young (
Two major rhyolitic tephra units (Lower and Upper Acigol Tuffs) have been erupted from the Acigol Complex. The Lower Acigol Tuff (>13 km(3) uncompacted volume) was erupted more than c. 180 ka ago, forming an extensive Plinian pumice-fall deposit with associated ashfall and ignimbrite. Well-developed ignimbrite veneer facies are preserved where the pyroclastic flows passed over hilly topography. Following the eruption, a thick rhyolite coulee (Bogazkoy obsidian) was extruded. The Upper Acigol Tuff eruption (age 70<t<150 ka) generated a second major Plinian deposit, an ignimbrite preserved up to 24 km from the vent, and an 80 m thick proximal succession of surge and fallout deposits; it resulted in collapse of the 6x5 km Acigol caldera. The two major tuffs are chemically similar but can be distinguished on the basis of lithic populations. Subsequent rhyolitic activity formed the c. 0.25 km(3) dome of Kocadag Tepe (c. 70 ka) and five dome/maar clusters (c. 20 ka). Late Quaternary and/or Holocene basalts and andesites surround the Acigol caldera, which developed in a zone of sinistral shear associated with approximate N-S compression. Vent distribution patterns, the eruption of young basalts, and the crystal-poor nature of the c. 20 ka rhyolites are consistent with basaltic stoking of a sizeable silicic magma chamber beneath the Acigol Complex.
High-resolution color reflectance records of KC01 and KC01B (Calabrian Ridge, Ionian Sea) are presented
and compared with a modified spliced high-resolution color reflectance record of Ocean Drilling Program
(ODP) Site 964. This comparison revealed that KC01B is characterized by intensive deformation between ∼27
and 28.5 m piston depth and that some sapropels are tectonically reduced in thickness. Moreover, the piston
coring has caused considerable stretching in the top of KC01 and KC01B. Using a new splice of ODP Site 964
as guide, previous astronomical tuned timescales of KC01B and ODP Site 964 were evaluated. This evaluation
resulted in a new sapropel-based astronomical timescale for the last 1.1 Myr. The new timescale implies a much
more uniform change in sedimentation rate for the Ionian Sea cores. Two prominent excursions to lighter values
in the δ¹⁸O record of the planktonic foraminiferal species Globigerinoides ruber occur during marine isotopic
stages 12 and 16 applying the new timescale. These shifts correspond with maxima in obliquity and are
punctuated by minima in the precession cycle. They are absent in global ice volume records and are interpreted
as reflecting a (summer) low-salinity surface water lens that floats on top of extremely saline intermediate and
deep waters at times of the very low sea levels during these glacial periods. All biostratigraphic and
magnetostratigraphic events found in KC01B and ODP Site 964 were re-dated according to the new timescale,
and the ages of 33 tephra layers were reviewed. The new ages for the Calabrian Ridge 2 and 3 magnetic events
in the Brunhes are concordant with minima in the global Sint800 composite record, derived from worldwide
deep-sea records of relative paleointensity and have been attributed to the Big Lost and La Palma excursions,
respectively.
Two alternative age models are presented for the Pleistocene part of the
Pliocene-Pleistocene boundary stratotype section at Vrica (Calabria,
southern Italy). Both age models, or chronologies, are based on the
correlation of the characteristic sapropel pattern to the summer
insolation time series of astronomical solution La90. The first age
model is based on the assumption that the succession is continuous,
whereas a global near synchroneity of the base of large-sized
Gephyrocapsa in oxygen isotope stages 48-49 is assumed in the second
model. This model implies that a major hiatus with exactly the same age
and duration is present in both the Vrica and Singa sections.
Cross-spectral analysis between sea surface temperature and
δ18O time series and the summer insolation target
yields highly significant coherencies in the precession and obliquity
frequency bands of the spectrum in cases where the continuous age model
is applied but results in less significant coherencies in cases where
the alternative age model is applied. According to the continuous model,
the position of almost all calcareous plankton datum planes relative to
the isotope stages is consistent with that found in the adjacent
northern Atlantic. The only marked exception is the base of large
Gephyrocapsa, which is found in stage 55 in the Mediterranean, whereas
it occurs in stage 48 (or top 49) in the open ocean. The alternative age
model solves the large Gephyrocapsa discrepancy but leads to significant
discrepancies in the position of other calcareous plankton events. On
the basis of these data sets, it is not justified to conclude which age
model is correct, although most arguments are in favor of the continuous
age model. This model is also supported by shipboard results from Ocean
Drilling Program Legs 154 and 160 sites.
During the Cenozoic widespread anorogenic magmatism, unrelated to recent supra-subduction zone modification of its mantle source, developed within the Mediterranean and surrounding regions; this is referred to collectively as the CiMACI (Circum-Mediterranean Anorogenic Cenozoic Igneous) province. On the basis of a comprehensive review of published and new major and trace element and Sr–Nd–Pb isotopic data (more than 7800 samples) for the magmatic rocks, a common sub-lithospheric mantle source component is identified for most of the region. This has geochemical affinities to the source of HIMU oceanic island basalts and to the European Asthenospheric Reservoir (EAR) and the Low Velocity Component (LVC) of previous workers; we refer to this as the Common Mantle Reservoir (CMR).
Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has been applied to the chemical analysis of fine-grained (125–250 μm) volcanic glass shards separated from tephra deposits. This has been used both for bulk sample analysis and for the analysis of individual shards. Initial work concentrated on the use of an infra-red (IR) laser operating at 1064 nm, which gave craters of the order of 200 μm and was suitable for the analysis of bulk samples. This technique requires of the order of 80 μg of sample to determine a full suite of trace elements. Modification of the laser optics to enable operation in the ultra-violet (UV, at 266 nm) enables craters between 5 and 50 μm diameter to be produced, and the UV laser couples better with glass than the IR laser. We have applied this UV laser system to the analysis of single shards from Miocene tephra deposits from the Ruby Range in south-west Montana. Detection limits are below 1 ppm for a wide range of petrogenetically significant elements, but are critically dependent upon operating conditions. Calibration is achieved using synthetic multi-element glasses, with internal standardisation provided from electron probe analyses. Analysis of single shards provides a wide range of data from a single sample, enabling (i) magmatic evolution to be discerned within one eruption and (ii) the identification of separate populations of shards within one deposit which may not be apparent from the electron probe data. In this paper we will present a summary of the techniques used for both bulk sample and single shard analysis and compare some new bulk analyses with analyses of glass derived from other analytical methods.
Tephra layers from archaeological sites in southern Italy and eastern Europe stratigraphically associated with cultural levels containing Early Upper Palaeolithic industry were analysed. The results confirm the occurrence of the Campanian Ignimbrite tephra (CI; ca. 40 cal ka BP) at Castelcivita Cave (southern Italy), Temnata Cave (Bulgaria) and in the Kostenki–Borshchevo area of the Russian Plain. This tephra, originated from the largest eruption of the Phlegrean Field caldera, represents the widest volcanic deposit and one of the most important temporal/stratigraphic markers of western Eurasia. At Paglicci Cave and lesser sites in the Apulia region we recognise a chemically and texturally different tephra, which lithologically, chronologically and chemically matches the physical and chemical characteristics of the Plinian eruption of Codola; a poorly known Late Pleistocene explosive event from the Neapolitan volcanoes, likely Somma–Vesuvius. For this latter, we propose a preliminary age estimate of ca. 33 cal ka BP and a correlation to the widespread C-10 marine tephra of the central Mediterranean. The stratigraphic position of both CI and Codola tephra layers at Castelcivita and Paglicci help date the first and the last documented appearance of Early Upper Palaeolithic industries of southern Italy to ca. 41–40 and 33 cal ka BP, respectively, or between two interstadial oscillations of the Monticchio pollen record – to which the CI and Codola tephras are physically correlated – corresponding to the Greenland interstadials 10–9 and 5. In eastern Europe, the stratigraphic and chronometric data seem to indicate an earlier appearance of the Early Upper Palaeolithic industries, which would predate of two millennia at least the overlying CI tephra. The tephrostratigraphic correlation indicates that in both regions the innovations connected with the so-called Early Upper Palaeolithic – encompassing subsistence strategy and stone tool technology – appeared and evolved during one of the most unstable climatic phases of the Last Glacial period. On this basis, the marked environmental unpredictability characterising this time-span is seen as a potential ecological factor involved in the cultural changes observed.
We present in this work a tephrostratigraphic record from a sediment piston core (JO 2004) from Lake Ohrid. Five tephra layers were recognised, all from explosive eruptions of southern Italy volcanoes. A multidisciplinary study was carried out, including stratigraphy, AMS 14C chronology and geochemistry. The five tephra layers were correlated with terrestrial proximal counterparts and with both marine and lacustrine tephra layers already known in the central Mediterranean area. The oldest is from Pantelleria Island (P11, 131ka BP). Other three tephra layers are from Campanian volcanoes: X6, Campanian Ignimbrite-Y5 and SMP1-Y3 (107, 39 and 31ka BP respectively). The youngest tephra layer corresponds to the FL eruption from Etna Volcano (3.4ka BP). In three cases these recognitions confirm previous findings in the Balkans, while two of them were for the first time recognised in the area, with a significant enlargement of the previous assessed dispersal areas.
The cyclic occurrence of sapropels appears to be associated with maxima in the 65°N summer insolation target curve. Studies of the most recent sapropel have revealed extensive oxidation of organic matter or even the complete removal of this unit. Geochemical and magnetic signals allow for the detection of such a “missing” sapropel. In older sediments, these signals are altered by ongoing diagenetic processes. An important parameter to reveal missing sapropels is Ba. Elevated concentrations of Ba are always found in visible sapropels, and even after oxidation of part of the sapropel, the initial Ba profile remains visible. We use this tool to trace down missing sapropels in KC01B, a 37-m Kullenberg core from the Calabrian Ridge, eastern Mediterranean. At least 8 of 11 sampled intervals around insolation maxima contain evidence of a completely oxidized sapropel: Ba, trace metal distributions, and magnetic parameters are similar to those observed around visible sapropels.
As many as 20 air-borne tephra layers have been identified in the upper Quaternary sequence of deep-sea cores from the eastern Mediterranean. Petrographical examination based on refractive index, phenocryst content, and chemical composition of the volcanic glass distinguishes the parent magma types: (1) tephritic, (2) alkalic-trachytic, (3) peralkalic-pantelleritic, and (4) calc-alkalic andesitic to rhyodacitic and alkali-basaltic. Tephra layers could be correlated with the following source volcanoes: Somma-Vesuvius, Roman district, Phlegraean Fields and Ischia, Pantelleria, Aeolian Islands, Mount Etna, and Aegean arc. The distribution for single layers has been traced over more than 2,000 km.
This work discusses the results of the characterisation study of two Lateglacial air-fall tephra layers found in long palaeoclimatic records from the volcanic lakes of Vico and Mezzano, in the northern Lazio region. Both tephra layers are about 0.5 cm thick; they are mostly made up of vesicular pumice pyroclasts and contain feldspar and black pyroxene. From the chemical point of view, both can be classified as benmoreites (sodic trachy-andesites). The available radiocarbon datings on the bracketing sediments indicate that both tephra layers were deposited about 14 ka BP. Because of the similarity of their macroscopic, microscopic and geochemical features and of the same chronological framework, the two layers can be correlated to each other. They are attributed to the tephra marker from Etna that has been found in marine and continental sediments of the Central Mediterranean. It formed during the final polyphasic eruption of the Eliittico volcano, that occurred 15-14 ka BP and represents a major explosive event in the evolution of Etna. This work enables to confirm the chronological framework of the two studied lacustrine sequences and allows to correlate them with other palaeoclimatic records, for more complete Late Quaternary climatic and environmental recontructions. The recovery of the Etnean Lateglacial tephra in the northern Lazio region extends its areal distribution towards the NNW and may contribute towards revised estimations of the volume of ejecta produced during the Etnean eruption. By integrating the available findings a distribution map has been constructed according which this tephra was deposited in two main fans so far recognized up to 600 km from the source: One extending to the SE and another extending to the N.
A study of calcareous nannofossils was carried out, using an optical microscope, on a set of eastern Mediterranean deep-sea cores. These cores were mainly colleced during cruise MD69, organized within the framework of the MAST-Marflux project. The main purposes of this paper are the assessment of a preliminary stratigraphy of "old" sapropels (i.e. never recovered in piston cores prior ro cruise MD69), the quantitative recognition of biostratigraphic events and their calibration with respect to magnetostratigraphy and isotope/faunal stages. Nannofossil biostratigraphy demonstrates that sapropels are present in the Pseudoemiliania lacunosa and in the underlying small Gephyrocapsa nannofossil zones. These findings are of key importance to link the deep- sea record to that of land sections (Calabria and Sicily, Southern Italy), where sapropelitic layers are present up to the large Gephyrocapsa/small Gephyocapsa zonal boundary. The beginning of the E. huxleyi Acme is calibrated with isotope/faunal stage 4. Based on astronomical dating of sapropels S1 (8 ka) and S3 (79 ka), this event is estimated to 51 +/- 2 ka (core Ban88-11GC) or 54 +/- 5ka (core Ban82-15PC). The E. huxleyi FAD cannot be confidently detected using the optical microscope technique. The LAD of P. lacunosa is estimated to 468 ka, based on interpolation between the Brunhes/Matuyama magnetic boundary (780 ka) and sapropel S9 (238 ka). With the same procedure the disappearance of Gephyrocapsa sp.3 (sensu Rio, 1982) from the Mediterranean is estimated to 584 ka. The FAD of Gephyocapsa sp. 3 and the "re-entrance" of medium sized Gephyrocapsa define the top of the small Gephyocapsa Zone, which is demonstrated to occur shortly after the end of the Jaramillo magnetic event in the Mediterranean area, with an interpolated age of 944 ka. An "acme" event of small Gephyrocapsa, beginning close to sapropel S9, is correlated with isotope stage 8 and dated as 265 ka.
After a discussion on the condensation of elements from the solar nebula, the REE abundances in Ca,Al-rich inclusions in carbonaceous chondrites are described and interpreted. The normalization values for REE in chondrites are examined at some length and the values of REE in other differentiated meteorites are reported.-R.A.H.
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Ash samples from tephra layers correlated with the Pomici di Avellino (Avellino Pumice) eruption of Somma-Vesuvius were collected in distal archives and their composition and particle morphology investigated in order to infer their behaviour of transportation and deposition. Differences in composition and particle morphologies were recognised for ash particles belonging to the magmatic Plinian and final phreatomagmatic phases of the eruption. The ash particles were dispersed in opposite directions during the two different phases of the eruption, and these directions are also different from that of coarse-grained fallout deposits. In particular, ash generated during magmatic phase and injected in the atmosphere to form a sustained column shows a prevailing SE dispersion, while ash particles generated during the final phreatomagmatic phase and carried by pyroclastic density currents show a general NW dispersion. These opposite dispersions indicate an ash dispersal influenced by both high and low atmosphere dynamics. In particular, the magmatic ash dispersal was first driven by stratospheric wind towards NE and then the falling particles encountered a variable wind field during their settling, which produced the observed preferential SE dispersal. The wind field encountered by the rising ash clouds that accompanied the pyroclastic density currents of the final phreatomagmatic phase was different with respect to that encountered by the magmatic ash, and produced a NW dispersal. These data demonstrate how ash transportation and deposition are greatly influenced by both high and low atmosphere dynamics. In particular, fine-grained particles transported in ash clouds of small-scale pyroclastic density currents may be dispersed over distances and cover areas comparable with those injected into the stratosphere by Plinian, sustained columns. This is a point not completely addressed by present day mitigation plans in case of renewal of activity at Somma-Vesuvius, and can yield important information also for other volcanoes potentially characterised by explosive activity.
We present new stratigraphic, palaeomagnetic, 87Sr/86Sr and 40Ar/39Ar data from a lacustrine
succession of the Sulmona basin, central Italy, which, according to an early study, included six unconformity bounded lacustrine units (from SUL6, oldest, to SUL1, youngest) spanning the interval >600 to 2 ka. The results of the present study, on the one hand confirm some of the previous conclusions, but by contrast reveal that units SUL2 and SUL1, previously attributed to the Holocene, are actually equivalent to the older SUL6 and SUL5 units – here dated to �814–>530 ka and �530–<457 ka, respectively – and that the U-series dates previously published for both former SUL2 and SUL1 units yielded abnormally young ages. In light of the present results, a reassessment of the chronology of the Sulmona basin succession and a revision of the tephrostratigraphy of the SUL2/SUL6 and SUL1/SUL5 units is in order.
A 37 m long piston core (KC-01B) was collected from the Calabrian Ridge in the Ionian Sea. Astronomical calibration of sapropels and sapropelic signals—based on rock-magnetic and geochemical properties—yields a very accurate time-frame for the last 1.1 Myr, with the exception of the interval (650–850 ka) straddling the Brunhes/Matuyama boundary. We used the oxygen isotope data as an additional constraint on our age model.
We arrive at an age of 812 ka for the Brunhes/Matuyama boundary, which indicates that its position is determined by delayed acquisition of NRM by some 40 kyr. The age of the top of Jaramillo subchron (100 ± 3 ka) is slightly older than that of Shackleton, Berger & Peltier (1990); that of its bottom (1072 ± 5 ka) concurs with their estimate.
In the Brunhes Chron, four short reversal excursions (CR0-3) were found and dated (CR0 261 ± 3 ka, CR1 318 ± 3 ka, CR2 515 ± 3 ka, CR3 573 ± 3 ka). In all cases, a highcoercivity reversed component is overlapped to a varying degree with a low-coercivity normal component. Three of the reversal excursions (CR1-3) occur in zones where diagenetic processes were shown to be minimal. The fourth (CR0), in which a very large coercivity overlap occurs, is not well expressed and is found in a zone where some dissolution of magnetic minerals has occurred.
The existing literature on reversal excursions is reviewed, and some of the older records with an oxygen isotope or sapropel record have been redated. CR0 could correspond to one of the Fram Strait excursions (Nowaczyk et al. 1994). CR3 corresponds to the Emperor, which is shown to be equivalent to the Big Lost reversal excursion. For CR1 and CR2 we propose the names Calabrian Ridge 1 and Calabrian Ridge 2, since correlation with existing reversal excursions is uncertain. The Blake was not detected because extensive diagenesis has occurred in the corresponding interval. All reversal excursions observed in KC-01B correspond to periods of minimal (relative) palaeointensity in the independently dated record of Valet & Meynadier (1993). This seems to imply that reversal excursions are more likely to occur in periods with a relatively large non-dipole field contribution
The influence of early diagenesis on the natural remanent magnetisation (NRM) in sediments from the Calabrian ridge (Central Mediterranean) is analysed with the help of fuzzy c-means (FCM) cluster analysis and non-linear mapping (NLM). The sediments are variably coloured: white, beige, purplish, greenish and grey layers occur with occasionally intercalated sapropels. The NRM acquired depends on both depositional conditions and diagenetic processes. To describe these, FCM was performed with chiin, ARM, CaCO3, Ba, Mn and S as variables. An eight-cluster model was derived with the clusters belonging to two categories: one expressing mainly diagenetic processes, i.e. dissolution and precipitation, and the other expressing mainly depositional conditions. The impact of diagenesis on NRM acquisition is profound and not restricted to the close vicinity of the anoxic sapropelitic layers. As a consequence, the influence of diagenetic processes on the NRM should be thoroughly assessed when selecting samples, e.g. for the determination of the relative palaeointensity of the geomagnetic field. Application of multivariate classification techniques appears to be useful because it links rock magnetic parameters to the geochemical environment. In the present piston core, three short reversed geomagnetic events in the Brunhes chron are preserved and, indeed, occur in clusters expressing no or minor diagenesis. The recording of the Blake event, however, has been prevented by later precipitation of magnetite in the corresponding interval.
Munno R. & Petrosino P., New constraints on the occurrence of Y-3 Upper Pleistocene tephra layer in the Tyrrhenian Sea. (IT ISSN 0394 - 3356, 2004). A widespread tephra layer, other than the well known Y-5, has been identified in the Upper Pleistocene marine succession in the Tyrrhenian Sea. Two investigated gravity cores showed, in fact, the presence of two companion pyroclastic tephra layers, separated by a varying thickness of pelagic sediments. The pyroclastic layers are mainly made up of pumice fragments and glass shards together with few K-feldspars and clino-pyroxene crystals. Both layers are alcali-trachytic in composition, even though a sharp difference emer- ges in the K/Na ratio that characterizes the two glasses. 14C dating of foraminiferous shells embedded in the clay layers directly underlying the most recent tephra gave an age of about 26 ka. An accurate review of literature regarding tephrostratigraphy in the Mediterranean area made it possible to correlate the older one to the Y-5 marker layer, joined to the Campanian Ignimbrite eruption, a paroxystic event in the Campi Flegrei area. The younger layer has been correlated with the Y-3 marker layer and probably represents another huge pyroclastic flow event from the Campanian area, whose products have not yet been distinguished in the field from those of typical Campanian Ignimbrite. This work clearly identifies the layer Y-3, firstly recorded by Keller et al. (1978), as the result of a speci- fic volcanic event different from the Campanian Ignimbrite (marker layer Y-5), defines its mineralogical and chemical composition together with its relative age offering an useful support for paleoclimatic and paleoenvinromental reconstruction of the sedimentation in the Tyrrhenian area.
With the aim of defining the chronological framework of the 51 m deep sedimentary sequence (core D) from Lago Grande di Monticchio (Mt Vulture volcano), macroscopic, microscopic and geochemical investigations have been carried out on the 14 thickest (at least 3 cm) tephra layers recorded in the core. The results indicate that the tephras are related to the main late Quaternary explosive events from Ischia, Vesuvius and the Phlegrean Fields districts of the Campanian area. Following these results, a usable time scale has been obtained, according to which the sequence spans the last 70 ka.Beyond the chronological information, this investigation has made it possible: (a) to identify widespread time-parallel markers for reliable correlations in the Central Mediterranean; (b) to collect useful data about past powerful eruptions, particularly from Vesuvius, for a better assessment of volcanic hazards in Central and Southern Italy.
A core drilled within the northern part of the city of Napoli has offered the unique opportunity to observe in one single sequence the superposition of the four pyroclastic flow units emplaced during the Campanian Ignimbrite (CI) eruption. Such a stratigraphic succession has never been encountered before in natural or in man made exposures. Therefore the CI sequence was reconstructed only on the basis of stratigraphic correlations and compositional data (in literature). The occurrence of four superposed CI flows, together with all the data available (in literature) allowed us to better constrain the chemical stratigraphy of the deposit and the compositional structure of the CI magma chamber. The CI magma chamber includes two cogenetic magma layers, separated by a compositional gap. The upper magma layer was contaminated by interaction with radiogenic fluids. The two magma layers were extruded either individually or simultaneously during the course of the eruption. In the latter case they produced a hybrid magma. But no evidence of input of new geochemically and isotopically distinct magma batches just prior or during the eruption has been found. Comparison with the exposed CI deposits has permitted reconstruction of variable eruption phases and related magma withdrawal and caldera collapse episodes. The eruption was likely to have began with phreatomagmatic explosions followed by the formation of a sustained plinian eruption column fed by the simultaneous extraction from both magma layers. Towards the end of this phase the upward migration of the fragmentation surface and the decrease in magma eruption rate and/or activation of fractures formed an unstable pulsating column that was fed only by the most-evolved magma layer. This plinian phase was followed by the collapse of the eruption column and the beginning of caldera formation. At this stage expanded pyroclastic flows fed by the upper magma layer in the chamber generated. During the following major caldera collapse episode, the maximum mass discharge rate was reached and both magma layers were tapped, generating expanded pyroclastic flows. Towards the end of the eruption, only the deeper and less differentiated magma layer was tapped producing more concentrated pyroclastic flows that traveled short distances.
During the Quaternary period, organic-rich black layers called sapropels
were intermittently deposited in the deep eastern Mediterranean Sea,
following high flood periods of the Nile River. During the past 250kyr,
timing of sapropel formation coincides with astronomically driven
maximum summer insolation in the northern tropics. The insolation
variations - described by a monsoon index - modulate the intensity of
the African monsoon feeding the Nile flood. Here, we report the
observation of a thick sapropel in eastern Mediterranean sediments that
conspicuously deviates from the usual pattern. The sapropel, dated at
528-525kyr by astronomical tuning of the stratigraphic oxygen-isotopic
record, is anomalous because the tropical summer insolation, while at a
peak at this time, was much lower than during the deposition of the more
recent sapropels. The Mediterranean climate was cold and dry, at least
at sea level. At the same time, in the equatorial Indian Ocean there was
an extreme event of low surface-water salinity caused by heavy monsoonal
fluvial discharge. The simultaneity, within dating uncertainties, of
unusually heavy monsoon rainfall over Africa and Asia while summer
insolation (and the monsoon index) was relatively low indicates a large,
regional-scale monsoon anomaly that cannot be explained in terms of
current understanding of astronomical forcing.
A 207-m-long core was taken from the deposits of a paleolake formed in the Vallo di Diano tectonic basin of the southern Apennines, Italy. Fourteen major tephra beds were identified and distributed into three groups based on stratigraphic position, and chemical and mineralogical compositions. In a pilot dating program, glass ages were determined for three of these layers using the 40Ar/39Ar method; two of those layers produced discordant step-heating spectra and provided anomalously old ages. A third layer produced a well-defined plateau age of 0.596±0.006 Ma (2σ) and from its stratigraphic position, is correlated to oxygen isotope (δ18O) stage 15 of the deep-sea record. The climatic history of the paleolake can be interpreted from down-core pollen and δ18O variations, which show a succession of two glacial–interglacial cycles. Extrapolation of ages from the astronomically tuned deep-sea δ18O record to that of the paleolake indicates that the lake existed for almost 0.2 Ma. Potential eruptive source regions for the tephra layers include the Roman Volcanic Province, Roccamonfina and perhaps Mt. Vulture. While further dating is needed, the Vallo di Diano section provides valuable information on Middle Pleistocene climate history for the central Mediterranean region and offers a comparison of terrestrial environmental history to those preserved in marine records.
The R1R2 chemical variation diagram, which includes all of the major cations, a mineralogical network, the degree of silica saturation, and the combined changes in and ratios in igneous rocks, is proposed where:R1 and R2 are parameters calculated either from chemical analyses (oxide percentages converted to millications) or modal data.Statistical distributions of “current rock names” are given for three large geochemical files: CLAIR, PETROS and RKFNSYS. A single classification grid, applicable to both volcanic and plutonic rocks, is proposed which is consistent with basic petrology. Successive belts spread from two fields, “peridotic” and “granitic or rhyolitic”, respectively, with a poorly-defined intersection in the region of intermediate rock compositions. The radial subdivisions crossing the successive belts are consistent with igneous differentiation suites. On the grid, isovalue lines of silica contents clearly cut across the boundaries between successive natural belts, except for the calc-alkaline series. Classifications based on silica contents are thus inconsistent with the current use of nomenclature. The grid has been applied to redefine the mean chemical compositions of 46 principal igneous rock types.
The paper reviews the existing data on the Y-3 tephra layer, first recognised in the Ionian Sea (Mediterranean basin). The collection and collation of old and new data on distal tephra occurrences in terrestrial, marine and lacustrine successions indicate that the Y-3 layer is dispersed over a wide area of the central Mediterranean basin. The peculiar homogeneous chemical composition of this layer makes its recognition rather straightforward and permits it being distinguished from other stratigraphically adjacent tephras. The best age estimate for the Y-3 layer of ca 30–31 cal ka BP, its peculiar stratigraphic position close to the Marine Isotope Stage 3/2 transition or Heinrich Event 3 onset, as well as its wide dispersion makes this layer an important marker to link and date late Pleistocene terrestrial and marine archives of the central Mediterranean basin.
a b s t r a c t Volcanic ash (tephra) erupted from the frequently active Campi Flegrei volcano forms layers in many palaeoenvironmental archives across Italy and the Mediterranean. Proximal deposits of 50 of the post-15 ka eruptions have been thoroughly sampled and analysed to produce a complete database of glass compositions (>1900 analyses) to aid identification of these units. The deposits of individual eruptions are compositionally diverse and this variability is often greater than that observed between different units. Many of the tephra units do not have a unique glass chemistry, with compositionally similar tephra often erupted over long periods of time (1000s years). Thus, glass chemistry alone is not enough to robustly correlate most of the tephra from Campi Flegrei, especially in the last 10 kyrs. In order to reliably correlate the eruption units it is important to take into account the stratigraphy, chronology, magnitude, and dispersal of the eruptions, which has been collated to aid identification. An updated chronology is also presented, which was constrained using Bayesian analysis (OxCal) of published radiocarbon dates and 40 Ar/ 39 Ar ages. All the data presented can be employed to help correlate post-15 ka tephra units preserved in archaeological and Holocene palaeoenvironmental archives. The new database of proximal glass compositions has been used to correlate proximal volcanic deposits through to distal tephra layers in the Lago di Monticchio record (Wulf et al., 2004, 2008) and these correlations provide information on eruption stratigraphy and the tempo of volcanism at Campi Flegrei.