Michael M. Joachimski

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• Prof. Dr.
• Professor (Associate) at Friedrich-Alexander-University Erlangen-Nürnberg

Our knowledge about climate change is based on the availability of climate data from both the present and the past. Accurate reference data are essential for improving Earth System Models, which help us to analyse and predict climatic developments with greater accuracy. In this context, subfossil landsnail shells and their stable isotope compositio...

Stable oxygen isotopes (δ18O) are routinely used to reconstruct sea-surface temperatures (SSTs) in the geological past, with mineral δ18O values reflecting a combination of the temperature and oxygen isotope composition of seawater (δ18Osw). Temporal variation of mean-ocean δ18Osw is usually accounted for following estimates of land-ice volume. Spa...

The development of terrestrial vegetation and its impact on silicate weathering is hypothesized to have driven multiple cooling events throughout the Paleozoic. One such event is the 8 to 10˚C cooling observed from the late Silurian through early Devonian (c.a. 420 to 385 Ma). Chemical weathering of Ca- and Mg-bearing silicate minerals and the subs...

The ultimate driver of the end-Permian mass extinction is a topic of much debate. Here, we used a multiproxy and paleoclimate modeling approach to establish a unifying theory elucidating the heightened susceptibility of the Pangean world to the prolonged and intensified El Niño events leading to an extinction state. As atmospheric partial pressure...

We present sequential oxygen isotope records (δ18Ophosphate vs. VSMOW) of horse tooth enamel phosphate of six individuals from two adjacent Palaeolithic sites in Lower Austria. Three molars from the site Krems-Wachtberg date to 33-31k cal a BP, and three molars from Kammern-Grubgraben to 24-20k cal a BP. All teeth show seasonal isotope variations,...

This study adopts a new approach describing palaeohydrology and palaeoclimates based on the interpretation of stable oxygen isotopes (δ18Op) recorded in fossil crocodilian teeth. They represent an archive of prime interest for tracking freshwater palaeoenvironmental change, applicable to many palaeontological localities in the world: crocodilian te...

Two Upper Devonian stratigraphic sections Pramosio A (PRA) and Freikofel T (FRKT) in the Carnic Alps of Italy and adjacent southern Austria representing continuous, entirely calcareous oxic sedimentation spanning the Frasnian-Famennian (Fr-Fm) boundary, were analysed for conodont biostratigraphy, facies and geochemistry. Lithologies are mainly pack...

Farabegoli et al., 2023 Supplementary Online Material BSPI 62(2) - 2023 https://www.paleoitalia.it/bollettino-spi/bspi-vol-622/

The Drewer quarry located in the Rhenish Massif is a well-studied outcrop that comprises Upper Devonian (Famennian) to Lower Carboniferous (Viséan) strata. Within the Drewer deposits two black shale intervals have been described that are linked to two global oceanic anoxic events, the Hangenberg Event and the Lower Alum Shale Event. The black shale...

This study adopts a new approach describing paleohydrology and paleoclimates based on the interpretation of stable oxygen isotopes (δ18Op) recorded in fossil crocodilian teeth. They represent an archive of prime interest for tracking freshwater paleoenvironmental change, applicable for many paleontological localities in the world: crocodilian teeth...

Ocean anoxia was one of the key killing mechanisms responsible for the end-Permian mass extinction (∼252 Ma). However, the temporal evolution and the triggering mechanisms of the end-Permian anoxia are controversial, with the current view being that the water column deoxygenation was a spatially and temporally heterogeneous event. Here, we use ceri...

The global climate of the Ordovician Period (486.9 to 443.1 Ma) is characterized by cooling that culminated in the Hirnantian glaciation. Chemical weathering of Ca- and Mg-bearing silicate minerals and the subsequent trapping of carbon in marine carbonates act as a sink for atmospheric CO2 on multi-million-year time scales, with basaltic rocks cons...

The Carnian Humid Episode (CHE) represents a dramatic dry to wet climate transition in the Late Triassic. Manifestations of this climate shift and its associated biological and environmental responses are not fully understood. Here, we carried out carbonate carbon isotope, trace metal, and pyrite framboid analyses at Wolonggang in southwest China t...

The oxygen isotope compositions of carbonate and phosphatic fossils hold the key to understanding Earth-system evolution during the last 500 million years. Unfortunately, the validity and interpretation of this record remain unsettled. Our comprehensive compilation of Phanerozoic δ¹⁸O data for carbonate and phosphate fossils and microfossils (total...

The sedimentary record of the Pahrump Group in Death Valley comprises well‐exposed successions of mixed carbonate and siliciclastic deposits. Despite the abundance of studies focussing on the depositional dynamics of mixed carbonate – siliciclastic deposition in the Phanerozoic, the record of similar Proterozoic examples is comparatively sparse. Us...

The Florida Canyon Zn deposit in the Bongará Province of northern Peru consists of sulfide and nonsulfide mineralizations within dolomitized strata of the Triassic Chambará Formation, a member of the Triassic-Jurassic Pucará Group. The nonsulfide mineralization, which represents one third of the total resource, formed by supergene alteration of Mis...

The end-Permian mass extinction, the largest biological crisis in Earth history, is currently understood in the context of Siberian Traps volcanism introducing large quantities of greenhouse gases to the atmosphere, culminating in the Early Triassic hothouse. In our study, the late Permian and Early Triassic atmospheric CO2 history was reconstructe...

The order Heterocorallia is an enigmatic, anatomically distinct group of calcifying Palaeozoic corals with unclear affinities to other, either extinct or modern cnidarian lineages. Here, we present results of microstructure and stable isotope studies on exceptionally well-preserved skeletons of two species of the heterocoral Oligophylloides from th...

The ultimate cause(s) of the end-Permian mass extinction (∼252 Ma ago) has been disputed. A complex interplay of various effects, rather than a single, universal killing mechanism, were most likely involved. Climate warming as consequence of greenhouse gas emissions by contemporaneous Siberian Traps volcanism is widely accepted as an initial trigge...

The link between the Permian–Triassic mass extinction (252 million years ago) and the emplacement of the Siberian Traps Large Igneous Province (STLIP) was first proposed in the 1990s. However, the complex cascade of volcanically driven environmental and biological events that led to the largest known extinction remains challenging to reconstruct. I...

Here we report on the oxygen isotope compositions of four proposed apatite reference materials (chlorapatite MGMH#133648 and fluorapatite specimens MGMH#128441A, MZ-TH, and ES-MM). The samples were initially screened for 18O/16O homogeneity using secondary ion mass spectrometry (SIMS) followed by δ18O determinations in six gas source isotope ratio...

The Cristal Zn prospect is located in the northernmost part of a wide mining district corresponding to the "Charlotte Bongará Zinc Project", which covers an area of approximately 110 km 2 in the Amazonas region in northern Peru. The mineralized area consists of many Zn occurrences that contain mixed sulfide and nonsulfide mineralizations. The nonsu...

A new Devonian oxygen isotope record based on 180 measurements of conodont apatite is reported from South China. The comparison with published Devonian δ¹⁸Oapatite data shows a considerable offset between records from different paleocontinents. This difference can be interpreted by regional variations in salinity, with the epicontinental seas havin...

The largest mass extinction since the advent of animals occurred during the Permian-Triassic (P-Tr) transition, ca. 252 Ma, and is commonly attributed to the eruption of the Siberian Traps large igneous province. However, the direct killing mechanism is still debated. In this study, we investigated marine redox conditions of the intermediate water...

The Eocene ´greenhouse´ climate represents the warmest period within the Cenozoic and has therefore become especially interesting as an analogue for estimated future climate scenarios. For paleo-climate reconstructions, bivalves represent valuable proxy archives with a high temporal resolution, due to their distinct, periodic layering (growth incre...

The Middle Devonian Epoch, ~ 393–383 million years ago, is known for a peak in diversity and highest latitudinal distribution of coral and stromatoporoid reefs. About 388 million years ago, during the late Eifelian and earliest Givetian, climax conditions were interrupted by the polyphased Kačák Episode, a short-lived period of marine dys-/anoxia a...

Horacek et al. (2021) commented on our publication arguing that we used an incorrect biochronology to define the Permian-Triassic (PT) boundary and that this inaccurate definition resulted in an erroneous interpretation of the oxygen isotope record in the studied Chanakhchi (former Sovestashen) section. Their comment gives us the opportunity to dis...

We present a δ 13 C carb chemostratigraphy for the Late Ordovician Hirnantian Stage based on 208 whole-rock samples from six outcrops in the Oslo-Asker district, southern Norway. Our data include the Norwegian type section for the Hirnantian Stage and Ordovician-Silurian boundary at Hovedøya Island. The most complete record of the Hirnantian Isotop...

The expansion of land plants is considered to have played a key role in triggering the Late Paleozoic Ice Age (LPIA), but evidence linking climatic events to terrestrial floral changes is limited. Here, we generated bulk carbonate δ13C, conodont δ18O and 87Sr/86Sr profiles from the lowermost Carboniferous of South China and Vietnam in order to inve...

The ore deposits of Bou Caïd (Ouarsenis, Algeria) occur in Jurassic and Cretaceous sedimentary rocks. The barite and Pb-Zn (Fe, Cu, and F) ore deposits of Bou Caïd belong to vein- and karst-type. The mineralization is represented in the whole area by a mixture of barite (currently still exploited) and nonsulfides consisting of hemimorphite, smithso...

SUPPLEMENT S1.-Response of organophosphatic brachiopods to environmental changes during the Lau/Kozlowskii Bioevent and the Mid-Ludfordian glaciation Mergl et al. (2018) described the stratigraphical distribution of organophosphatic brachiopods from the uppermost part of the Neocucullograptus inexpectatus to the lower part of Monograptus parultimus...

Focusing on the Shuixiakou Section (Xikou area, Zhen’an County, Shaanxi Province, southeastern Qinling region, China), the Roadian-Wordian conodonts are investigated. More than 2 000 conodont elements including 6 genera and 14 species have been obtained. Based on these materials, the Guadalupian Jinogondolella nankingensis and J. aserrata zones hav...

The Late Devonian is considered as a crucial climatic transition from the Devonian greenhouse to Carboniferous icehouse. Published Late Devonian marine palaeotemperature records are mainly based on conodont δ¹⁸Oapatite data from the Rheic Ocean. In order to reconstruct palaeotemperature variations in the eastern Palaeotethys, oxygen isotopes were m...

The present study reviews the main geochemical, sedimentological, and paleontological events associated with one of the largest perturbations in the Phanerozoic carbon cycle, the Mid-Ludfordian Carbon Isotope Excursion (MLCIE), which is globally documented in Late Silurian marine successions. Climate changes associated with the MLCIE are not yet we...

Results of conodont-based δ¹⁸Ophos studies from two core sections in Estonia (Mehikoorma-421 and Valga-10) indicate that the pre-Hirnantian Late Ordovician was characterized by a general cooling trend: a rapid climate cooling in the early Sandbian and a less intense cooling in the late Sandbian through Katian. During this time interval, sea-surface...

Middle to Late Ordovician carbonates were collected in South China (Anhui Province) from the Kuniutan, Datianba, and Pagoda formations in the Dingxiang and Daling sections and analysed for high‐resolution carbon isotope chemostratigraphy. An increase by 0.4‰ in δ¹³Ccarb is observed in the upper part of the Kuniutan Formation (Eoplacognathus pseudop...

Conodont ecology of the Early Triassic Smithian–Spathian transition is still poorly understood. Here we use oxygen isotope ratios of monogeneric conodonts from Omani samples to reveal the differences of oxygen isotopic composition between different taxa. Oxygen isotope analyses from Oman reveal that Neogondolella inhabited a deeper part of the wate...

The Cambrian succession of the Tingskullen drill core from northern Öland comprises Cambrian Series 2 and Miaolingian (Wuliuan Stage) siliciclastic strata. The major portion of the succession is represented by the Miaolingian Borgholm Formation, which, in ascending order, is subdivided into the Mossberga, Bårstad and Äleklinta members. The Äleklint...

The Hangenberg crisis represents a mass extinction marked by a biodiversity turnover at the Devonian–Carboniferous boundary. However, the last million years before this dramatic event have been poorly investigated. Here we report new data on the size and abundances of vertebrate remains as well as carbon isotope data from the latest Famennian in th...

In this paper we study the Lilang Super Group in the Spiti area, Indian Himalaya to understand environmental changes in the aftermath of the end-Permian mass extinction. We focus on the Mikin and Kaga Formations, which span the Induan to Ladinian stages of the Lower and Middle Triassic. These strata formed on the southern mid-palaeolatitude margin...

The 6th volume of the MAAO series details the results of two seasons of excavation carried out on Karacamirli Tepe 5, a small hill near the southern bank of the river Kura in Shamkir District, Azerbaijan. The site was first occupied in the 5th millennium BC, from which several pits containing pottery and obsidian could be studied. After the mid-2nd...

Chemical weathering of Ca- and Mg-bearing silicate minerals and the subsequent trapping of carbon in marine carbonates act as a sink for atmospheric CO2, driving shifts in global climate on geologic time scales. However, the role of silicate weathering in the fluctuating paleoclimate of the Devonian Period (419 to 359 Ma) is poorly understood. Alth...

Climate changes close to the Lochkovian-Pragian Event are still widely discussed. Carbonate δ18O and δ13C and conodont apatite δ18O from medial to distal carbonate ramp sediments were analysed to provide further stable isotope data from the stratotype area in the Prague Basin. The uppermost Silurian to lower Emsian δ18O trends are put into an updat...

The largely covered Middle Ordovician succession in the classic geological Röstånga area in northwestern Scania has not been studied for some 80 years. A new drill core through a succession ranging from the lower–middle Darriwilian to the lower Sandbian has provided a unique opportunity to investigate the graptolite biostratigraphy and the δ13Corg...

Recent exploration of the Gorno Zn-Pb-Ag deposit in northern Italy identified 3.3 Mt of sulfides at 4.9% Zn, 1.3% Pb, and 27.2 g/t Ag (indicated+inferred resources), and a further mineralized nucleus of mixed sulfides-nonsulfides in the Val Vedra area, currently under evaluation. The ores are hosted in Triassic limestone and shale. Sulfides (sphale...

Metacarbonate assemblages in high-grade metamorphic terranes often pose challenges when trying to distinguish between mantle-derived carbonatite and sedimentary carbonate protoliths. We present a study of granulite-facies metacarbonate samples of the putative Munnar carbonatite described as decimeter-thick dikes and veins, and layers of a meter-thi...

Minerals of the apatite group, especially hydroxylapatite Ca5(PO4)3OH, are valuable archives for reconstructing environmental conditions occurring throughout the Earth's history (e.g., Joachimski et al. 2009). Apatite oxygen isotope compositions have proved useful in studies of conodonts as well as fish and mammalian teeth and bones. Secondary ion...

The Cenozoic genus Terebratula seems to be an exception to the post-Permian trend in brachiopod retreat to offshore habitats, because it was species rich and numerically abundant in warm-temperate shallow-water environments in the Mediterranean and the Paratethys realms. This was so despite the general dominance of bivalves and the pervasive biotur...

The Carnian-Norian (C-N) transition (Late Triassic) has long been postulated as an interval of major climatic changes, though the nature of such changes and their ecological impact remains largely unexplored. We use oxygen isotopes measured on monogeneric conodont assemblages (δ 18 O PO4) from the Canadian Cordillera to trace seawater temperature e...

Stable isotope measurements of carbonate and phosphate fossils provide the foundation for quantitative study of deep-time climate change and its link to the carbon cycle. Despite this, such data have only been organized in spreadsheets until now. To facilitate application of isotope data to studies of the Earth system, we have created a relational...

Variations in the ¹⁸O/¹⁶O ratio of marine fossils and microfossils record changes in seawater ¹⁸O/¹⁶O and temperature and provide the basis for global correlation. Based on more than 64,000 measurements, this chapter presents oxygen isotope curves for Phanerozoic foraminifera, mollusks, brachiopods, and conodonts, as well as for Precambrian limesto...

In order to understand the processes of stone formation, compositional, spectroscopic, mineralogical and crystallographic characteristics of human urinary stones collected from patients in Sri Lanka were investigated in detail. The data showed that the majority of urinary calculi were calcium oxalate, either whewellite or weddellite. Other solid ph...

The Serpukhovian Stage, proposed by NIKITIN (1890), was re-established in the Russian stratigraphic scheme in 1974 by the Interdepartmental Stratigraphic Committee of the USSR and has become internationally recognized as the upper stage of the Mississippian Subsystem (HECKEL & CLAYTON 2006). The base of the Serpukhovian has not been defined by a Gl...

Permian-Triassic boundary sections from Armenia were studied for carbon isotopes of carbonates as well as oxygen isotopes of conodont apatite in order to constrain the global significance of earlier reported variations in the isotope proxies and elaborate the temporal relationship between carbon cycle changes, global warming and Siberian Trap volca...

Reconstructing marine paleoenvironments from the skeletal hardparts of nektic organisms is often hampered by their unknown migrational pathways involving different water masses and their corresponding physico-chemical parameters. Despite significant progress over the last years, the reconstruction of migration patterns of extinct ammonoids is diffi...

The Carnian Humid Episode is an interval of prominent climatic changes in the Late Triassic. We studied the carbon isotope (δ¹³C) geochemistry of carbonates from sections in southwestern China and northern Oman. δ¹³C records from the Yongyue section (western Guizhou, South China) show a progressive positive shift from 1.4 to 2.8‰ in the early to mi...

In Scandinavia, the boundary between provisional Cambrian Stage 4 and the Wuliuan Stage is marked by a prominent unconformity ascribed to non-deposition and erosion during a eustatic sea-level fall that may partially correlate with the regressive ’Hawke Bay Event’. Wuliuan strata are widely distributed in Scandinavia, but exposures are relatively f...

The Famennian (Late Devonian) started after and ended with two of the seven largest crises of the Phanerozoic, the Kellwasser and Hangenberg events, respectively. In between, global environmental trends have been identified, involving cooling and eustatic regression. Tropical and subtropical marine faunas were largely cosmopolitan. Overall, this su...

We evaluate the potential of ophiolites as archives of paleoseawater and hydrothermal fluid compositions by analysing the chemical and isotopic composition of abiogenic carbonates, precipitated from fluids within the oceanic crust of the 91 Ma Troodos Ophiolite, Cyprus. Calculated variations in fluid Mg/Ca, Sr/Ca and ⁸⁷Sr/⁸⁶Sr with temperature with...

The Grönhögen-2015 core drilling on southern Öland, Sweden, penetrated 50.15 m of Cambrian Series 3, Furongian and Lower–Middle Ordovician strata. The Cambrian succession includes the Äleklinta Member (upper Stage 5) of the Borgholm Formation and the Alum Shale Formation (Guzhangian–Tremadocian). Agnostoids and trilobites allowed subdivision of the...

A recent core drilling in the geologically classical Fågelsång area resulted in a 58.70-m-long drill core through the lowermost Sandbian Sularp Shale, the Darriwilian Almelund Shale and Komstad Limestone, and part of the late Tremadocian to earliest Darriwilian Tøyen Shale. The shales contain zone index graptolites that are used for an update of th...

The Cristal Zn prospect consists of a mixed sulfide and nonsulfide mineralization located in the Bongará province (Amazonas region, northern Peru). The mineralization is hosted by carbonate rocks of the Pucará Group, deposited in a Mesozoic extensional basin on the western margin of the Brazilian-Guyana shield. Zinc sulfides at Cristal occur in the...

The Komstad Limestone forms a distal part of the widespread ‘orthoceratite limestone’ of the Baltoscandian continent. In this paper, we present an integrated conodont biostratigraphy and carbon isotope stratigraphy for a major part of this formation and address its significance for evaluating Middle Ordovician correlation and overall stratigraphy....

We present a multi-proxy study of an upper Paleocene-lower Eocene succession from the paleo-equatorial region. The study is carried out on a coal-bearing, shallow-marine succession exposed at Jathang, east Khasi hills, Meghalaya, northeastern India. The succession was deposited in a low-energy, coastal marsh-bay complex. Dinoflagellate cyst biostra...

A preliminary C–O stable isotopes geochemical characterization of several nonsulfide Zn-Pb Tunisian deposits has been carried out, in order to evidence the possible differences in their genesis. Nonsulfide ores were sampled from the following deposits: Ain Allegua, Jebel Ben Amara, Jebel Hallouf (Nappe Zone), Djebba, Bou Grine, Bou Jaber, Fedj el A...

The Verkhnyaya Kardailovka section is one of the best candidates for the GSSP (Global Stratotype Section and Point) at the base of the Stage (Mississippian). For boundary definition, the first appearance of the conodont Lochriea ziegleri Nemirovskaya, Perret et Meischner, 1994 in the lineage Lochriea nodosa (Bischoff, 1957)−L. ziegleri is used. L....

Biogenic minerals such as dental apatite have become commonly analysed archives preserving geochemical indicators of past environmental conditions and palaeoecologies. However, post-mortem, biogenic minerals are modified due to the alteration/replacement of labile components, and recent moves to utilise micro-mammal tooth d18O signatures for refine...

Zinc nonsulfides are well represented in the Middle East, with occurrences in Turkey, Iran, and Yemen. Their genesis can be constrained by using carbon and oxygen isotope systematics applied to carbonate minerals. The δ¹³C ratios of smithsonite and hydrozincite in Iran and Turkey are comprised in the typical interval of supergene Zn carbonates (−0....

Zinc nonsulfides are well represented in the Middle East, with occurrences in Turkey, Iran, and Yemen. Their genesis can be constrained by using carbon and oxygen isotope systematics applied to carbonate minerals. The δ 13 C ratios of smithsonite and hydrozincite in Iran and Turkey are comprised in the typical interval of supergene Zn carbonates (−...