Antonio Langone

• Professor
• Professor of Geochemistry at University of Pavia

Mylonites and pseudotachylytes play a crucial role in defining the rheology of extending continental crust. In this context, determining the age of brittle-ductile deformation is fundamental to understanding the rifting evolution stages. Here, we investigate the Premosello Shear Zone, an extensional structure of the Ivrea-Verbano lower crust, where...

Mantle xenoliths (lherzolites and a wehrlite) found in Cenozoic alkaline lavas from Azrou–Timahdite (Middle Atlas, Morocco) were petrographically studied with a particular emphasis on mineral chemistry. The most striking feature of these rocks is that plagioclase formed as a result of Al-rich spinel destabilization. This reaction is recorded in dif...

The study of accessory phases, including trace element concentrations and radiogenic isotopes, provides powerful information for a better understanding of geological processes such as crustal anatexis. These accessory minerals are the primary carriers of many incompatible elements and Rare Earth Elements (REE) in crustal rocks. In this contribution...

Here, we present an overview of the main results of several studies from different mid/low-crustal shear zones exposed in the Ivrea-Verbano Zone (Southern Alps, Italy). In particular, we aimed to constrained the shear zone activity by combining monazite and titanite U-(Th-)Pb data. As main result, our studies revealed different but complementary b...

Recent works have demonstrated that water-fluxed melting is an effective mechanism to produces large volumes of low-temperature silicic melts at relatively low pressure, with important consequences for localization of deformation and the rheology of the continental crust (e.g., Collins et al., 2016; 2020; Tafur & Diener, 2020). Yet, several argumen...

Titanite-bearing calc-silicates and mafic gneisses, metamor- phosed under amphibolite- to granulite-facies conditions, crop out in Val d’Ossola area (Ivrea-Verbano Zone, Italy). The Ivrea-Verbano Zone represents an exhumed section of the pre-Alpine middle to lower continental crust which es- caped the Alpine subduction, thus provides a unique op- p...

In this contribution, we investigate compositionally heterogeneous mylonites (i.e., amphibolites vs. calc-silicates) with the aim to decipher which and how deformation behaviour promoted the strain localisation in a fully ductile regime. To address this issue, we integrate microstructural, petro-chemical data and microscale rheological modelling th...

High- to ultrahigh-pressure (HP–UHP) rocks recording high-temperature (HT) > 700 °C are well exposed in the Central Alps, making it an ideal region to study the timing of metamorphic stages and the mechanisms of deep-seated rocks exhumation. Here, we report an integrated dataset of petrological and U–(Th–)Pb dating of metapelites surrounding ultram...

The Balmuccia peridotite exposes relatively fresh mantle rocks at the Earth’s surface, and as such it is of interest for geologists and geophysicists. The outcrop is a kilometre-scale feature, yet its extent at depth is insufficiently imaged. Our aim is to provide new constraints on the shape of the density anomaly this body represents, through 3D...

The Bajgan Complex (BC) in the North Makran Domain (Makran Accretionary Prism, SE Iran) has been considered a remnant of a Paleozoic metamorphic continental basement detached from the southernmost edge of the Lut Block. We present here new geochronological and petrological data on metamorphic rocks from this Complex, intending to assess the age and...

Here, we study the relationships of titanite-hosting microdomains, intragrain chemical variations, microstructure and fluids with the aim of deciphering the reliability of titanite U-Pb dating to constrain the age of deformation in mylonitic rocks. We investigate these relationships in a post-Variscan amphibolite-facies shear zone developed in the...

The presence of recently intruded granites at Earth's surface suggests that their exhumation may have occurred rapidly. The Neogene granites of the Tuscan Magmatic Province (Italy) were emplaced during a period of extensional tectonics and are ideal for determining and quantifying the exhumation process. The peraluminous monzogranite of Giglio Isla...

Al Huwaysah 010 is an ungrouped achondrite meteorite, recently referred to as a brachinite‐like meteorite. This meteorite, showing a fine‐grained assemblage of low‐Ca pyroxene and opaque phases, is strongly reduced in comparison to other reduced brachinites. The occurrence of some tiny plates of graphite and oldhamite in this meteorite suggests tha...

The present study investigates the origin of a ∼ 400 m thick peridotite-pyroxenite sequence, locally known as Rocca d'Argimonia, which is encased within the lowest levels of the ∼8 km thick Mafic Complex, a gabbro-dioritic batholith from the lower continental crust section of the Ivrea-Verbano Zone (Southern Alps). The broad purpose of this work is...

Tracking melt migration in the lower crust is a foundational step in understanding the formation of Earth's crust. The Finero Mafic Complex of the Ivrea-Verbano Zone, Italy, exposes Mesozoic granulite to amphibolite grade gabbroic gneisses that are variably overprinted by brittle to semi-ductile fabrics inferred to have formed during the Late Creta...

Detailed characterization was performed on the chalcedonies from the jasperoids of the Pietratonda–Poggio Peloso Sb–Au deposit (southern Tuscany, Italy). The main purpose was to retrieve information on the geothermal fluids that formed the chalcedonies and the source of antimony concentrations. Investigations were performed using optical microscopy...

Provenance and Types of Xenoliths of the Giglio Monzogranitic Intrusion

The Variscan high-grade metamorphic basement of northern Sardinia and southern Corsica record lower Carboniferous anatexis related to post-collisional decompression of the orogen. Migmatites exposed in the Punta Bianca locality (Italy), consist of quartz + biotite + plagioclase + K-feldspar orthogneisses, garnet and cordierite-bearing diatexite and...

The trace‐element composition of rutile is commonly used to constrain P‐T‐t‐conditions for a wide range of metamorphic systems. However, recent studies have demonstrated the redistribution of trace elements in rutile via high‐diffusivity pathways and dislocation‐impurity associations related to the formation and evolution of microstructures. Here w...

Local variations of metamorphic record from compositionally heterogeneous rocks: Inferences on exhumation processes of (U)HP-HT rocks (Cima di Gagnone, Adula-Cima Lunga unit) Stefania Corvò1,2, Matteo Maino1,2, Antonio Langone2, Filippo Luca Schenker3, Leonardo Casini4, Sandra Piazolo5, and Silvio Seno1,3 1Department of Earth and Environmental Sc...

The formation of shear zones is crucial to understand the deformation of the crust and the evolution of rifted margins. However, despite their intrinsic importance, a detailed characterization of the compositional and structural patterns of shear zones is often lacking, resulting in poorly constrained models of shear initiation. In this contributio...

Patterns of Late Cretaceous terrestrial vertebrate diversity across North America have been interpreted primarily in terms of biogeographic provincialism driven by latitude or coastal-inland habitat gradients. A major difficulty in determining the influence of these two gradients is the existence of some large gaps in the terrestrial fossil record,...

The B/Ca ratio in calcareous marine species is informative of past seawater CO32- concentrations, but scarce data exist on B/Ca in coralline algae. Recent studies suggest influences of temperature and growth rates on B/Ca, the effect of which could be critical for the reconstructions of surface ocean pH and atmospheric pCO2. In this paper, we prese...

The Red Sea rift system represents a key case study of the transition from a continental to an oceanic rift. The Red Sea rifting initiated in Late Oligocene-Early Miocene (⁓24-23 Ma) and was accompanied by extensive magmatism throughout the rifted basin, from Afar and Yemen to northern Egypt. Here, we present a petrological and geochemical study of...

The recycling of volatile and incompatible elements through the entire Earth's history is one of the most important processes for the chemical evolution of the lithosphere. In this context, amphiboles are important hydrous minerals playing a key role in the chemical differentiation of the crust–mantle system. We carried out amphibole–liquid partiti...

In our reply we demonstrate the inconsistency of the comment we received from Mazzarini et al. Our data, models and conclusions are solid and framed in the regional evolution of the Northern Apennines, typified by eastward migration of coeval extensional tectonics and magmatism since late Miocene. We show that understanding the natural processes re...

In the Makran area, a wide accretionary wedge is originated by the north-dipping subduction of the Neo-Tethyan oceanic lithosphere. The rear of the accretionary wedge is represented by the North Makran Domain that consists of an imbricate stack of tectonic units derived from the closure of the North Makran oceanic basin. This oceanic basin opened s...

Shear zones localise most of deformation in narrow areas and provide efficient ways to mobilize significant volumes of fluids and melts up and down the crust. Deformation may localise if a specific domain focuses higher differential stress or strain rate with respect the host rocks. This concentration is commonly associated with variations in rock...

Titanite is a useful accessory mineral for understanding crustal processes because is considered as a powerful petrochronometer that allows to determine both age (U-Pb isotopes) and pressure-temperature (P–T) conditions (trace-element composition: Zr, rare earth elements (REE)). However, titanite has a propensity to recrystallize during metamorphis...

In this work a rare and attractive blue diopside present in Sissone valley in the Western Alps was investigated through different methodologies: geological survey; standard gemological methods; X-Ray Powder Diffraction; SEM observations; Raman spectrometry; EMP analyses of major elements; and LA-ICP-MS analyses for minor and trace elements. The hos...

The direct observation and investigation of rift-related structures at the mesoscale is uncommon. Hence, detailed constraints on the evolution of the main faults and shear zones developed during crustal extension are not always available. The Ivrea-Verbano Zone, in the Italian Southern Alps, samples remnants of the former lower crust of the rifted...

Complete and accurate chemical characterisation was performed on a repertoire of glass tableware and lighting-ware from San Lorenzo in Carmignano (Apulia, Italy). Twenty-three samples were investigated by scanning electron microscopy, electron microprobe analysis for major and minor elements, laser ablation inductively coupled plasma mass spectrome...

Zircon is a common accessory mineral in evolved magmatic rocks and its investigation can provide unevaluable geochronological and geochemical information. The lower continental crust forming the Ivrea-Verbano Zone (IVZ, Southern Alps) locally shows the discordant intrusion of swarms of felsic dykes, which petrology was poorly constrained. Corundum-...

The Ivrea Verbano Zone (IVZ, Western Alps) is an exhumed section of the pre-Alpine middle to lower continental crust made of (ultra-)mafic rocks intruded into high grade metapelites and metabasites that escaped Alpine subduction. Following the Variscan orogeny, indeed, the IVZ was affected by post-orogenic extension and subsequently, in the Triassi...

The record of metamorphic conditions is commonly highly heterogeneous in spatially close rocks of different composition and rheology. The well-studied Cima di Gagnone area in the Central Alps represents such an example, as relatively small, 1– to 100 s-meter scale, ultrahigh–pressure and high–temperature ultramafic lenses are enveloped within amphi...

Exhumation and cooling of upper crustal plutons is generally assumed to develop in the brittle domain, thus determining an abrupt passage from crystallization to faulting. To challenge this general statement, we applied an integrated approach involving meso- and micro-structural studies, thermochronology, geochronology and rheological modelingto th...

A newly identified high-temperature shear zone, the Badrinath shear zone (BSZ), is described within the metamorphic core of the Himalayan belt along the Alaknanda valley, Garhwal Himalaya (NW India). A multidisciplinary approach comprising fieldwork, microstructural analyses, petrology and in situ monazite geochronology was addressed to this high-s...

High‐pressure (HP) mineral parageneses are usually poorly developed within metagranitoids, as these rocks are commonly affected by fluid‐deficient conditions when experiencing a metamorphic cycle. However, since ductile shear zones can act as preferential pathways for fluids in the Earth’s crust, if metagranitoids are involved in ductile shear unde...

The Skoura inlier in the Moroccan High Atlas consists of thick Precambrian–Paleozoic formations. It displays, in the western part near Aguerzega village, a volcano-sedimentary succession of about 400 m thickness. It includes a variety of welded and non-welded ignimbrites, lapilli-tuff fallout deposit, coherent lava, sedimentary mass flow deposit an...

This study proposes new data on the rare pyroxene, variety violane, sampled from its type locality, Praborna manganese deposit, near Saint Marcel (Val d’Aosta, Italy). Violane is very appreciated as a gemstone for its different hues of violet-blue color and is characterized by its diopsidic or omphacitic composition. To assess the possible causes o...

The B / Ca ratio in calcareous marine species is informative of past seawater CO32− concentrations, but scarce data exist on B / Ca in coralline algae (CA). Recent studies suggest influences of temperature and growth rates on B / Ca, the effect of which could be critical for the reconstructions of surface ocean pH and atmospheric pCO2. In this pape...

The North Makran domain (southeast Iran) is part of the Makran accretionary wedge and consists of an imbricate stack of continental and Neo-Tethyan oceanic tectonic units. Among these, the Band-e-Zeyarat ophiolite consists of (from bottom to top): ultramafic cumulates, layered gabbros, isotropic gabbros, a sheeted dyke complex, and a volcanic seque...

The poor knowledge on the Archean mantle composition arises a series of problems spanning from the effective chondritic composition of the Earth to how volatile elements (hydrogen, oxygen, chlorine and fluorine) were added to the Earth and how their deep cycle evolved giving origin to life. Because the Archean mantle is poorly preserved, Archean ko...

U-Pb spot ages have been determined on detrital zircons from two samples of volcaniclastic arenites belonging to the Tufiti di Tusa Formation (TTF) outcropping in the Lucanian Apennines (Southern Italy). Many petrographic and geochemical studies have been performed on these sandstones with the aim of defining their detritus source. A new and precis...

Twenty-one sandstone samples belonging to the intermediate part of Gorgoglione Flysch (GF) dated Middle-Miocene, cropping out in the Southern Apennines (Italy), have been studied to highlight the detritus provenance. Petrographic and chemical composition indicates that the successions consist of feldspatho-quartzose and litho-feldspatho-quartzose a...

In the Monte Duria area (Adula-Cima Lunga unit, Central Alps, N Italy) Grt-peridotites occur in direct contact with migmatised orthogneiss (Mt. Duria) and eclogites (Borgo). Both mafic and ultramafic rocks share a common HP peak at 2.8 GPa and 750°C and post-peak static equilibration at 1.2 GPa and 850 °C (Tumiati et al., 2018). Grt-peridotites sho...

In the Monte Duria area (Adula-Cima Lunga unit, Central Alps, N Italy) Grt-peridotites occur in direct a common HP peak at 2.8 GPa and 750 °C and post-peak static equilibration at 1.2 GPa and 850 °C. Grt-peridotites show abundant amphibole, dolomite, phlogopite and orthopyroxene after olivine, suggesting that they experienced metasomatism by crust-...

The Monte Duria area is located in the southern part of the Adula Nappe complex on the northeastern side of the Como Lake (N Italy). Garnet/chlorite peridotites were found within Bt-rich migmatitic gneiss or in direct contact with amphibole-bearing migmatites containing boudins of variably granulitised eclogites. The contact between mafic and ultra...

This study is focused on a barian titanian phlogopite found in an alkaline ultramafic dyke transecting Mesozoic limestones of the Gargano Promontory (Apulia, Italy). The rock containing the barian titanian phlogopite, an olivine-clinopyroxene-rich lamprophyre with nepheline and free of feldspars, has been classified as monchiquite. The present stud...

Detailed geological field mapping, integrated with meso- and microstructural investigations, kinematic of the flow and finite strain analyses, combined with geochronology, are fundamental tools to obtain information on the temperature–deformation–timing path of crystalline rocks and shear zone. The Posada-Asinara shear zone (PASZ) in northern Sardi...

Corundum-rich (up to 55 vol.%) felsic dykes formed with albite, ±K-feldspar, ±hercynite and ±biotite-siderophyllite cut the lower crustal rocks exposed in the Ivrea–Verbano Zone (NW Italy). Zircon is an abundant accessory mineral and its investigation through laser ablation-inductively coupled plasma (multi-collector)-mass spectrometer (LA-ICP-(MC)...

In convergent zones, several parts of the geodynamic system (e.g., continental margins, back-arc regions) can be deformed, uplifted, and eroded through time, each of them potentially delivering clastic sediments to neighboring basins. Tectonically driven events are mostly recorded in syntectonic clastic systems accumulated into different kinds of b...

Corundum-rich (up to 55 vol.%) felsic dykes formed by albite, ±K-feldspar, ±hercynite and ±biotite-siderophyllite cut the lower crustal rocks exposed in the Ivrea-Verbano Zone (NW Italy). Zircon is an abundant accessory mineral and its investigation through LA-ICP-(MC)MS has allowed to directly constrain the timing of emplacement, as well as petrol...

New tectono-metamorphic data along the Alaknanda-Dhauli Ganga valleys in the Garhwal Himalaya (NW India) are presented focusing on sheared rocks of the Main Central Thrust zone (MCTz), one of the first order regional structures in the Himalaya. In regard of large hot orogens (LHOs), the MCTz corresponds to the base of the low-viscosity infrastructu...

A c. 500 m wide and 1.5 km long body consisting of basic to ultrabasic rocks, metamorphosed up to granulite-facies and retrogressed to amphibolite-facies conditions during the Variscan orogeny, crops out near Olbia (NE Sardinia, Italy). Among abundant samples, one, collected from a garnet-rich centimetric layer, was chosen for a detailed analysis o...

Petrographic and geochemical data for mylonites from a metric-scale shear zone in mantle peridotites from the Finero massif (Southern Alps) record large mineralogical and geochemical modifications compared to surrounding coarse-grained ultramafic rocks, which were pervasively deformed in presence of hydrous melts. The mylonites are composed by oliv...

In the Monte Duria area (Adula-Cima Lunga unit, Central Alps, N Italy) garnet peridotites occur in direct contact with migmatised orthogneiss (Mt. Duria) and eclogites (Borgo). Both eclogites and ultramafic rocks share a common high pressure (HP) peak at 2.8 GPa and 750 °C and post-peak static equilibration at 0.8–1.0 GPa and 850 °C. Garnet peridot...

The Tertiary Piedmont Basin (TPB) in NW Italy represents an episutural basin developed since the Late Eocene in the retrobelt of the Western Alps and in the foreland of the Northern Apennine. During Oligo-Miocene time, up to 3 km-thick clastic deposits filled the basin recording the tectonics associated with the shift from the Alpine collisional th...

The occurrence of (ultra)high pressure and high temperature mineralogical assemblages developed during the Alpine phases makes the Cima di Gagnone area (Cima Lunga unit) one of the most studied area in the Central Alps. It consists of continental basement rocks (orthogneisses, paragneisses and metapelites) enveloping (ultra-) mafic bodies of oceani...

Constraining the source terranes of Alpine siliciclastic flysch sequences is crucial for building a clearer picture of the palaeogeography and geodynamic evolution of the Western Tethys in the framework of impending continental collision. This paper presents an integrated study that involves palaeocurrent dispersal analysis, sandstone petrography a...

In Val d’Ala (Piedmont, Western Alps, Italy), the more interesting rocks for the mineralogical research are represented by rodingites (rich in mineralized veins and fractures) associated with serpentinites in the eclogitized oceanic crust of Piemonte Zone, south of Gran Paradiso Massif. Among the vein-filling minerals, garnets are the most apprecia...

The studied area is situated in the Ivrea-Verbano Zone, which consists of a Variscan continental lower crustal section showing Permian to Carboniferous magmatism and high temperature metamorphism overprinted by ductile deformation occurred at high temperature conditions during Jurassic time. In particular, the area of Premosello-Vogogna-Val d’Ossol...

Despite melt inclusions in migmatites and granulites provide a wealth of information on crustal anatexis in different geological scenarios, a complete compositional study (including trace elements and H2O) is yet to be made for the Himalayan rocks. In this contribution, we focus on nanogranitoids occurring in peritectic garnet of migmatites from Ka...

The Asinara Island, NW Sardinia, is an exceptionally well-preserved segment of medium to high-grade metamorphic Variscan crust. Starting from the pioneering studies (Di Pisa et al., 1993; Del Moro et al., 1996; Carosi et al., 2004) describing the main features of the metamorphic and structural setting, we focus on petrology and geochronology of me...

The Cima Lunga unit represents one of the most studied area in the Central Alps thanks to the occurrence of (ultra)high pressure and high temperature mineralogical assemblages developed during the Alpine phases. It consists of continental basement rocks (orthogneisses, paragneisses and metapelites) hosting (ultra-) mafic relicts of oceanic crust (e...

Periadriatic Alpine magmatism has long been attributed to slab breakoff after Adria‐Europe continental collision, but this interpretation is challenged by geophysical data suggesting the existence of a continuous slab. Here we shed light on this issue based on a comprehensive dataset of zircon U‐Pb ages and Hf isotopic compositions from the main we...

The research focused on a collection of 37 Late Antique glass fragments, found at the archaeological site of San Giusto (southern Italy). The analyses performed by SEM-EDS, EMPA and LA-ICP-MS showed that all samples are constituted by natron-based soda-lime silica glass and allowed clarifying the distinction between Egyptian HIMT1 and HIMT2 product...

The Red Sea rifting nucleated within the Neoproterozoic Arabian-Nubian shield, which formed during the Pan-African orogeny over a time period of about 300 million years. The Red Sea rifting started about at 30 Ma and was assisted by much diffused magmatism that lasted until recent times. The majority of magmatic rocks consist of basalts that consti...

In the early 2000s, an exceptional discovery of gem-quality multi-coloured tourmalines, hosted in Litium-Cesium-Tantalum (LCT) pegmatites, was made in the Adamello Massif, Italy. Gem-quality tourmalines had never been found before in the Alps, and this new pegmatitic deposit is of particular interest and worthy of a detailed characterization. We st...

Despite intensive research efforts and significant advances in the understanding of subduction and obduction processes that affected several units which at the present day compose the Western Alps, the paleogeographic evolution of the Alpine Tethys represents a debated topic in Alpine geology. The role of the opposing continental margins (passive E...

The Central Alps host the largest field of Tertiary pegmatites of the Alps. In this study we investigate an area of the pegmatite field in the upper Valle dei Ratti, at the southwestern border of the Bergell Pluton. In the study area several sets of discordant dykes with different orientations and different features crosscut each other. The aims of...

A rare example where the inferred boundary between Earth’s lower continental crust and upper mantle outcrops at the surface is the Ivrea-Verbano Zone (IVZ) of the Sothern Alps. The northernmost mafic suite of the IVZ is the Finero Complex, which hosts the Finero Peridotite massif which is unique amongst Ivrea peridotites for its high proportion of...

The Finero mantle peridotite (Phlogopite Peridotite unit, Ivrea Verbano Zone, Italy) mainly consists of harzburgites, dunite, subordinate lherzolites and pyroxenites. These rocks ubiquitously possess hydrous minerals, i.e. pargasite and phlogopite, locally in large amount (up to 25 vol.%). According to literature data, Finero peridotites and pyroxe...

One of the peculiarities of the Ivrea-Verbano Zone (IVZ, Southern Alps, Italy) is the presence of several mantle bodies, among which those famous of Finero, Balmuccia and Baldissero, within lower continental crustal rocks. Despite the numerous studies on these mantle lenses, the mechanisms and the geodynamic settings leading to their emplacement in...

The Yalaxiangbo gneiss dome (SE Tibet) in eastern Himalaya is one of the major metamorphic culminations in the Tethyan Himalayan Sequence, referred to as North Himalayan Gneiss Domes (NHGD). It comprises three main tectonic units separated by an upper ductile/brittle and a lower ductile detachment. The upper tectonic unit, above the upper ductile/b...

This paper is a new crystallographic and chemical insight including REE and other trace elements of garnets from the “garnet dike”, located in Val Codera (Central Alps, Italy). The crystals may reach up to 2 cm with trapezohedral shape and show a homogeneous dark red colour; however, there are also present many eye-visible inclusions and cracks. Th...

In the Western Alps, a steeply dipping km-scale shear zone (the Ferriere-Mollières shear zone) cross-cuts Variscan migmatites in the Argentera-Mercantour External Crystalline Massif. Structural analysis joined with kinematic vorticity and finite strain analyses allowed to recognize a high-temperature deformation associated with dextral transpressio...

The Early Paleozoic evolution of the northern margin of Gondwana is characterized by several episodes of bimodal magmatism intruded or outpoured within thick sedimentary basins. These processes are well recorded in the Variscan blocks incorporated in the Ligurian Alps because they experienced low temperature Alpine metamorphism. During the Paleozoi...

A geochronological study was performed on zircon grains from a middle-lower crustal shear zone exposed in the northern sector of the Ivrea-Verbano Zone (Southern Alps, Italy) for the first time. The shear zone developed at the boundary between mafic rocks of the External Gabbro Unit and ultramafic rocks of the Amphibole-Peridotite Unit. It is ~10–2...

The Monte Duria area is located in the southern part of the Adula Nappe complex on the northeastern side of the Como Lake (N Italy). Garnet/chlorite peridotites were found within Bt-rich migmatites or in direct contact with migmatitic Amp+Pl gneiss containing boudins of variably granulitised eclogites. The contact between mafic and ultramafic rocks...