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Responsable d’équipe : Régis Doucelance
L’équipe de géochimie regroupe une vingtaine de chercheurs et enseignants-chercheurs. Les activités de recherche s’organisent autour de 3 grandes thématiques :
- Source, genèse et chronologie des magmas
- Géodynamique chimique
- Processus magmatiques en contexte continental
- Eléments volatils et dégazage des magmas
- Le cycle des éléments volatils dans le manteau
- Comportement des éléments traces, cinétique du dégazage et nouveaux traceurs
- Evolution de la Terre Primitive
- Origine, composition de la Terre, évolution précoce et environnements primitifs
- Géodynamique archéenne
Le parc instrumental se compose d’un spectromètre de couplage à plasma inductif d’émission de type ICP-AES (HORIBA Jobin Yvon Ultima C), et de spectromètres de masse ICPMS (Agilent 7700 et Element 2), d’un MC-ICPMS Neptune Plus et de deux TIMS (Triton, Triton Plus), d’une chaîne de comptage α et β et 2 spectromètres α et β pour la datation et le dosage des éléments radioactifs des séries U-Th. Le système laser excimer 193nm Resonetics M-50E peut être relié aux différents ICPMS selon les applications (traces, géochronologie U-Th-Pb, isotopes Pb, Nd, Hf) . Ce parc instrumental est complété par des salles blanches surpressées dédiées aux différentes méthodes et équipées de hottes à flux d’air laminaire.
Liste du personnel
27 personnes trouvées
Équipe Géochimie – février 2024 - Analyses des éléments majeurs : ICP-AES (UCA Partner)
- Comptage nucléaire
- ICPMS Ablation Laser
- MC-ICPMS Neptune
- Microanalyse CHNS-O (UCA Partner)
- Salle blanche de chimie
- Salle de chimie : fusion alcaline
- TIMS Triton
- TIMS Triton Plus
Rang A :
63 publication(s) trouvée(s).
- Bosse V., Godard G., Devidal J.L., Mallens J., Shea T. (2024). Two metamorphic cycles recorded by monazite in eclogite-facies gneisses (Southern Armorican Massif, France): A Cambro- Ordovician continental crust involved in eo-Variscan subduction. BSGF - Earth Sciences Bulletin vol.195, p.20, - DOI:10.1051/bsgf/2024018 - .
- Bouloton J., Gasquet D., Pin C., Schumacher A. (2024). Felsic xenoliths in Triassic quartz-monzodiorite dykes from the central Jebilet (Morocco): Detailed petrography and geochemistry, with a critical assessment of the so-called “granulitic” samples. Journal of African Earth Sciences vol.219, p.105349, - DOI:10.1016/j.afrearsci.2024.105349.
- Bénard A., Ionov D., Nebel O., Arculus R.J. (2024). Boninitic melt percolation makes depleted mantle wedges rich in silica: COMMENT. Geology vol.52, p.e572, 3, - DOI:10.1130/G51824C.1 - .
- Cluzel D., Trotet F., Paquette J.L. (2024). Petrology and Geochemistry of an Unusual Granulite Facies Xenolith of the Late Oligocene Post-Obduction Koum Granodiorite (New Caledonia, Southwest Pacific): Geodynamic Inferences. Minerals vol.14, p.466, - DOI:10.3390/min14050466 - .
- Cluzel D., Trotet F., Paquette J.L. (2024). Petrology and Geochemistry of an Unusual Granulite Facies Xenolith of the Late Oligocene Post-Obduction Koum Granodiorite (New Caledonia, Southwest Pacific): Geodynamic Inferences. Minerals vol.14, 5, - DOI:10.3390/min14050466 - .
- Cravinho A., Rosa D., Relvas J.M.R.S., Solá A.R., Pereira I., Paquette J.L., Borba M.L., Tassinari C.C.G., Chew D., Drakou F., Breiter K., Araujo V. (2024). From source to surface: clues from garnet-bearing Carboniferous silicic volcanic rocks, Iberian Pyrite Belt, Portugal. Contributions to Mineralogy & Petrology vol.179, p.32, - DOI:10.1007/s00410-024-02106-3 - .
- Cravinho A., Rosa R., Relvas J.M.R.S., Solá A.R., Pereira I., Paquette J.L., Borba M.L., Tassinari C.C.G., Chew D., Drakou F., Breiter K., Araujo V. (2024). From source to surface: clues from garnet-bearing Carboniferous silicic volcanic rocks, Iberian Pyrite Belt, Portugal. Contributions to Mineralogy & Petrology vol.179, - DOI:10.1007/s00410-024-02106-3 - .
- El Bakili, A., Corsini M., Bosse V., Lardeaux J.M. (2024). Metamorphic and chronological records of early Permian continental collision in Beni Bousera granulites (Internal Rif belt): implications for the tectonic evolution of northern Morocco during Pangea construction. Jouranl of Geological Society - DOI:10.1144/jgs2024-018 - .
- Engels T., Monteux J., Boyet M., Bouhifd A. (2024). Large impacts and their contribution to the water budget of the Early Moon. Icarus - DOI:10.1016/j.icarus.2024.116124 - .
- Ferreira A., Stevens G., Moyen J.F., Rossouw R., Dominguez H. (2024). Metamorphic history of amphibolite facies metapelites from the Southern margin of the Limpopo Belt: In situ U-Pb dating of Zircon, monazite and rutile. Precambrian Research vol.413, - DOI:10.1016/j.precamres.2024.107566 - .
- Frossard P., Bonnand P., Boyet M., Bouvier A. (2024). Role of redox conditions and thermal metamorphism in the preservation of Cr isotopic anomalies in components of non-carbonaceous chondrites. Geochimica et Cosmochimica Acta vol.367, p.167-178, - DOI:10.1016/j.gca.2023.12.022 - .
- Fumes R.A., Luvizotto G.L., Pereira I., Moraes R. (2024). Trace element changes in rutile from quartzite through increasing P–T from lower amphibolite to eclogite facies conditions. vol.537, p.231-248, Minor Minerals, Major Implications: Using Key Mineral Phases to Unravel the Formation and Evolution of Earth's Crust, Edited By: V. van Schijndel, K. Cutts, I. Pereira, M. Guitreau, S. Volante, M. Tedeschi, The Geological Society (ed.), - DOI:10.1144/SP537-2022-207.
- Hammouda T., Frossard P., Boyet M., Bouvier A., Newville M., Lanzirotti A. (2024). Mapping the redox state of the young Solar System using ytterbium valence state. Geochimica et Cosmochimica Acta - DOI:10.1016/j.gca.2024.03.018 - .
- Haruel C., Bani P., Tari D., Nauret F., Rose-Koga E. (2024). Formation of new beaches from lahar deposits, Ambae volcano, Vanuatu. Bulletin of Volcanology vol.86, - DOI:10.1007/s00445-024-01755-3 - .
- Ibrahim Y., Rey P.F., Whitney D.L., Teyssier C., Roger F., Bosse V., Cenki B. (2024). From dome to duplex: Convergent gravitational collapse explains coeval intracratonic doming and nappe tectonics, central Australia. Geology - DOI:10.1130/G51721.1 - .
- Inostroza M., Moune S., Aguilera F., Vlastélic I., Burckel P., Tapia J., Irarrázabal N., Fernández B. (2024). Lastarria volcano, a major emitter of boron and chalcophiles in northern Chile and the Central Volcanic Zone. Chemical Geology vol.670, p.122416, - DOI:10.1016/j.chemgeo.2024.122416 - .
- Kitoga L.S., Zakharov D., Marin-Carbonne J., Boyet M., Moyen J.F., Di Rocco T., Pack A., Olivier N., Stevens G. (2024). Oxygen and silicon isotopic compositions of Archean silicified lava and cherts of the Onverwacht Group: Implication for seafloor hydrothermalism and the nature of recycled components in the source of granitoids. Chemical Geology - DOI:10.1016/j.chemgeo.2024.122407 - .
- Lacerda S., Guitreau M., Gonçalves L. Gonçalves L., Moreira H., Castro C., Pinheiro M.A., Costa C., Doucelance R. (2024). Paleoproterozoic sediment-derived magmas reveal a late orogenic stage in the southern São Francisco Craton, Brazil: evidence from petrogenesis of the 2.0 Ga Cupim Pluton leucogranites. Lithos p.107852, - DOI:10.1016/j.lithos.2024.107852 - .
- Laurent O., Guitreau M., Bruand E., Moyen J.F. (2024). At the Dawn of Continents: Archean Tonalite-Trondhjemite-Granodiorite Suites. Elements vol.20, p.174-179, 3, - DOI:10.2138/gselements.20.3.174 - .
- Maria Lo Forte F., Schiavi F., Rose-Koga E., Rotolo S.G., Verdier-Paoletti M., Aiuppa A., Zanon V. (2024). High CO2 in the mantle source of ocean island basanites. Geochimica et Cosmochimica Acta - DOI:10.1016/j.gca.2024.01.016 - .
- Matthews S.W., Caracciolo A., Bali E., Halldórsson S., Sigmarsson O., Guðfinnsson G., Pedersen G.B.M., Gunnarsson Robin J., Marshall E.W., Aden A.A., Ýr Gísladóttir B.B., Bosq C., Auclair D., Merrill H., Levillayer N., Löw N., Hlín Rúnarsdóttir R., Johnson S.M., Steinþórsson S., Drouin D. (2024). A dynamic mid-crustal magma domain revealed by the 2023 to 2024 Sundhnúksgígar eruptions, Iceland. Science - DOI:10.1126/science.adp8778 - .
- Monteux J., Boyet M. (2024). Modalités de séparation noyau/manteau: contraintes géochimiques et dynamiques. vol.Chapitre 2, p.43-69, Structure et dynamique de l'intérieur de la Terre 1 dynamique du manteau terrestre / Monteux J. éd sc./ ISTE edition. ISBN 9781789481723.
- Moyen J.F., Mccoy-West A.J., Bruand E., Millet M.A., Nebel O., Cawood P.A., Saji N., Ladwig A., Klaver M., Elburg M. (2024). Felsic crust development in the Kaapvaal Craton, South Africa: A reference sample collection to investigate a billion years of geological history. Earth-Science Reviews vol.250, - DOI:10.1016/j.earscirev.2024.104680 - .
- O'neil J., Rizo H., Reimink J., Garçon M., Carlson R.W. (2024). Earth’s Earliest Crust. Elements - DOI:10.2138/gselements.20.3.168 - .
- Otto T., Stevens G., Moyen J.F., Mayne M.J., Clemens J.D. (2024). Peritectic orthopyroxene entrainment during partial melting of garnet peridotite produced the Bushveld Complex chromite deposits. Mineralium Deposita - DOI:10.1007/s00126-024-01277-0 - .
- Pereira I., van Schijndel V, Tedeschi M., Cutts K., Guitreau M. (2024). A review of detrital heavy mineral contributions to furthering our understanding of continental crust formation and evolution. vol.537, p.9-55, Minor Minerals, Major Implications: Using Key Mineral Phases to Unravel the Formation and Evolution of Earth's Crust, Edited By: V. van Schijndel, K. Cutts, I. Pereira, M. Guitreau, S. Volante, M. Tedeschi, Geological Society, London, Special Publications (ed.), - DOI:10.1144/SP537-2022-250.
- Pin C., Gannoun A.M. (2024). Evaluation of two methods allowing the full preparation in a single day of silicate rocks in view of radiogenic isotope (Nd, Sr, and Pb) analyses. Journal of Analytical Atomic Spectrometry vol.39, 204, - DOI:10.1039/d3ja00305a - .
- Quemet A., Lasnier G., Mialle S., Isnard H., Boyet M., Garçon M., Auclair D. (2024). Reference value of the JNdi-1 isotopic material without normalization. Journal of Analytical Atomic Spectrometry - DOI:10.1039/D4JA00140K - .
- Royer L., Terray L., Rubéo-Lisa M., Sudre J., Gauthier P.J., Claude A., Giammanco S., Pecora E., Principato P., Breton V.J. (2024). Lessons Learnt from Monitoring the Etna Volcano Using an IoTSensor Network through a Period of Intense Eruptive Activity. Sensors vol.24, p.1577, 5, - DOI:10.3390/s24051577 - .
- Seydoux-Guillaume A.M., Rochette P., Gardes E., Zanetta P.M., Sao-Joao S., de Parseval P., Glass B.P. (2024). Clues on the Australasian impact crater site inferred from detailed mineralogical study of a monazite inclusion in a Muong Nong tektite. Geology vol.109, p.1578-1590, 9, - DOI:10.1130/G52522.1 - .
- Sigmarsson O., Larsen G., Hervé-Carpentier G. (2024). Rapid differentiation of mafic to intermediate magma constrained by Ra–Th disequilibrium and the size of magma chamber beneath Hekla volcano, Iceland. Contributions to Mineralogy & Petrology vol.179, 66, - DOI:10.1007/s00410-024-02148-7 - .
- Turuani M.J., Seydoux-Guillaume A.M., Laurent A.T., Fougerouse D., Harley S.L., Reddy S.M., Goncalves P., Saxey D.W., Michaud J., Montel J.-M., Nicollet C., Paquette J.L. (2024). From ID-TIMS U-Pb dating of single monazite grain to APT-nanogeochronology: application to the UHT granulites of Andriamena (North-Central Madagascar). Bulletin of Geosciences vol.195, Special Issue Some applications of LA-ICP-MS U-Pb geochronology: A tribute to Jean Louis Paquette Marc Poujol, Valérie Bosse and Dave Chew (Guest Editors), 18, - DOI:10.1051/bsgf/2024013 - .
- Van Schijndel V., Cutts K.A., Pereira I., Guitreau M., Volante S., Tedeschi M. (2024). Minor minerals, major implications: using key mineral phases to unravel the formation and evolution of Earth's crust. vol.537, p.1-7, Minor Minerals, Major Implications: Using Key Mineral Phases to Unravel the Formation and Evolution of Earth's Crust, Edited By: V. van Schijndel, K. Cutts, I. Pereira, M. Guitreau, S. Volante, M. Tedeschi, Geological Society, London, Special Publications (ed.), - DOI:10.1144/SP537-2023-110.
- Volante S., Blereau E., Guitreau M., Tedeschi M., van Schijndel V., Cutts K. (2024). Current applications using key mineral phases in igneous and metamorphic geology: perspectives for the future. vol.537, p.57-121, Minor Minerals, Major Implications: Using Key Mineral Phases to Unravel the Formation and Evolution of Earth's Crust, Edited By: V. van Schijndel, K. Cutts, I. Pereira, M. Guitreau, S. Volante, M. Tedeschi, - DOI:10.1144/SP537-2022-254.
- van Schijndel V., Cutts K., Pereira I., Guitreau M., Volante S., Tedeschi M. (2024). Minor minerals, major implications: using key mineral phases to unravel the formation and evolution of Earth's crust. vol.537, Minor Minerals, Major Implications: Using Key Mineral Phases to Unravel the Formation and Evolution of Earth's Crust, Edited By: V. van Schijndel, K. Cutts, I. Pereira, M. Guitreau, S. Volante, M. Tedeschi, Geological Society, London, Special Publication (ed.), - DOI:10.1144/SP537.
- Bablon M., Nauret F., Saillard M., Samaniego P., Vlastélic I., Hidalgo S., Le Pennec J.L., Ratzov G., Michaud F., Mothes P., Liorzou C., Gannoun A.M. (2023). An innovative isotopic method to identify the volcanic source of distal tephra. Earth and Planetary Science Letters vol.619, p.118283, - DOI:10.1016/j.epsl.2023.118283 - .
- Bonnand P., Boyet M., Bosq C. (2023). Stable cerium isotopes as a tracer of oxidation reactions. Geochemical Perspectives Letters vol.28, p.27-30, - DOI:10.7185/geochemlet.2340.
- Bruand E., Storey C., Fowler M., Dhuime B., Doucelance R. (2023). Mineral-whole rock isotope fidelity? A comparative study of Hf-Nd-O from high Ba-Sr granitoids. Chemical Geology vol.624, p.121425, - DOI:10.1016/j.chemgeo.2023.121425 - .
- Burton M., Aiuppa A., Allard P., sensio-Ramos M., Pardo Cofrades A., La Spina A., Nicholson E.J., Zanon V., Barrancos J., Bitetto M., Hartle M., Romero J.E., Waters E., Stewart A., Hernández P.A., Lages J.P., Padrón E., Wood K., Esse B., Hayer C., Cyrzan K., Rose-Koga E., Schiavi F., D’Auria L., Pérez N.M. (2023). Exceptional eruptive CO 2 emissions from intra-plate alkaline magmatism in the Canary volcanic archipelago. Communications Earth & Environment vol.4, p.467, - DOI:10.1038/s43247-023-01103-x - .
- Decraene M.-N., Marin-Carbonne J., Thomazo C., Brayard A., Bouvier A.-S., Bomou B., Adatte T., Olivier N. (2023). Pyrite iron isotope compositions track local sedimentation conditions through the Smithian-Spathian transition (Early Triassic, Utah, USA). Palaeogeography, Palaeoclimatology, Palaeoecology vol.617, p.11507, - DOI:10.1016/j.palaeo.2023.111507 - .
- Doucet L., Moine B., Cottin J.Y., Paquette J.L., Renac C., Li Z.X. (2023). Kerguelen carbonatite tuff sourced from deep recycled material. Earth and Planetary Science Letters vol.621, p.118375, - DOI:10.1016/j.epsl.2023.118375 - .
- Flahaut J., Payet V., Fueten F., Guitreau M., Barthez M., Ito G., Allemand P. (2023). New Detections of Feldspar-Bearing Volcanic Rocks in the Walls of Valles Marineris, Mars. Geophysical Research Letters vol.50, p.e2022GL100772, - DOI:10.1029/2022GL100772 - .
- François C., Baludikay B.K., Debaille V., Birck J.L., Limmois D., Jourdan F., Baudet D., Paquette J.L., Delvaux D., Javaux E.J. (2023). Multi-method dating constrains the diversification of early eukaryotes in the Proterozoic Mbuji-Mayi Supergroup of the D.R.Congo and the geological evolution of the Congo Basin. Journal of African Earth Sciences vol.198, p.104785, - DOI:10.1016/j.jafrearsci.2022.104785.
- Förster F., Reynaud S., Sauzéat L., Ferrier-Pagès C., Samankassou E., Sheldrake T.E. (2023). Increased coral biomineralization due to enhanced symbiotic activity upon volcanic ash exposure. Science of the Total Environment p.168694, - DOI:10.1016/j.scitotenv.2023.168694 - .
- Glodji L.A., Bascou J., Paquette J.L., Yessoufou S., Ménot R.P., Amponsah P.O. (2023). Geochronology and geochemistry of igneous rocks of the Dassa region, Central-Benin: evidence of an Ediacaran emplacement of alkali-calcic and alkaline plutonic and volcanic magmas. International Journal of Earth Sciences vol.112, p.1331-1360, - DOI:10.1007/s00531-023-02293-7.
- Harris A., Latutrie B., Van Wyk De Vries B., Saubin E., Foucher M., Gurioli L., Zanella E., Médard E., Nauret F. (2023). Emplacement of monogenetic lava flows on eroded terrain, Part II: The case of the Arti`ere valley (Grave Noire, France). Journal of Volcanology and Geothermal Research vol.438, p.107812, - DOI:10.1016/j.jvolgeores.2023.107812.
- Israel C., Boyet M., Doucelance R., Bonnand P., Dhuime B., Ionov D., Moreira H., Jackson M.G., Golovin A.V. (2023). First Ce-Nd isotope measurements of middle and lower continental crust samples support massive lower crust recycling over Earth's history. Lithos vol.460-461, p.107369, - DOI:10.1016/j.lithos.2023.107369 - .
- Jayananda M., Guitreau M., Aadhiseshan K.R., Miyazaki T., Chung S.L. (2023). Origin of the oldest (3600–3200 Ma) cratonic core in the Western Dharwar Craton, Southern India: Implications for evolving tectonics of the Archean Earth. Earth Sciences Reviews vol.236, p.104278, - DOI:10.1016/j.earscirev.2022.104278 - .
- Narvaez D., Samaniego P., Koga K., Rose-Koga E., Hidalgo S., Ratzov G. (2023). Two types of slab components under Ecuadorian volcanoes supported by primitive olivine-hosted melt inclusion study. Lithos vol.442-443, p.107049 107049 107049, - DOI:10.1016/j.lithos.2023.107049 - .
- Nicol L., Garçon M., Boyet M., Gannoun A.M. (2023). High-precision measurement of europium isotopic composition of geological reference materials by multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS). Journal of Analytical Atomic Spectrometry - DOI:10.1039/d3ja00042g - .
- Pereira I., Bruand E., Nicollet C., Koga K., Brovarone A.V. (2023). Ti-Bearing Minerals: from the Ocean Floor to Subduction and Back. Journal of Petrology - DOI:10.1093/petrology/egad041 - .
- Petersson A., Kemp A.I.S., Boyet M., Whitehouse M.J., Boyce M., Roberts M., Kennedy A. (2023). Response of Sm–Nd isotope systematics to complex thermal histories: A case study from 3.58 Ga gneisses of the Pilbara Craton. Earth and Planetary Science Letters vol.620, p.118346, - DOI:10.1016/j.epsl.2023.118346 - .
- Pin C., Piro J.L. (2023). Characterization of a Set of Improved, CMPO-Based, Extraction Chromatographic Resins: Applications to the Separation of Elements Important for Geochemical and Environmental Studies. Solvent Extraction and ion exchange - DOI:10.1080/07366299.2023.2206861 - .
- Polo-Sánchez A., Flaherty T., Hervé G., Druitt T., Fabbro G., Nomikou P., Balcone-Boissard H. (2023). Tracking timescales of magma reservoir recharge through caldera cycles at Santorini (Greece). Emphasis on an explosive eruption of Kameni Volcano. Frontiers in Earth Science vol.11, - DOI:1I 10.3389/feart.2023.1128083 - .
- Pouget M., Moussallam Y., Rose-Koga E., Sigurdsson H. (2023). A reassessment of the sulfur, chlorine and fluorine atmospheric loading during the 1815 Tambora eruption. Bulletin of Volcanology vol.85, - DOI:10.1007/s00445-023-01638-8 - .
- Rivera M., Samaniego P., Nauret F., Marino J., Liorzou C. (2023). Petrological and geochemical constraints on the magmatic evolution at the Ampato-Sabancaya compound volcano (Peru). Lithos vol.458-459, p.107364, - DOI:10.1016/j.lithos.2023.107364 - .
- Rusquet A., Famin V., Quidelleur X., Michon L., Nauret F., Danisik M., Thinon I., Leroy S., Lemoine A. (2023). Pliocene-to-Holocene volcano-tectonic activity on Mohéli Island (Comoros archipelago) constrained by new K Ar ages. Journal of Volcanology and Geothermal Research vol.442, p.107896, - DOI:10.1016/j.jvolgeores.2023.107896 - .
- Sigmarsson O. (2023). Reply to comment on “Long or short silicic magma residence time beneath Hekla volcano, Iceland?” by Sigmarsson O, Bergþórsdóttir I A, Devidal J‑L, Larsen G, Gannoun A. Contributions to Mineralogy & Petrology vol.178, p.72, - DOI:10.1007/s00410-023-02051-7 - .
- Trull C., Juste B., Gauthier P.J., Sancho M. (2023). Estudio de las técnicas de medida de gas radón en volcanes: caracterización de la biodisponibilidad del radón en áreas volcánicas. RADIOPROTECCIÓN p.21-29, 108, - .
- Vlastélic I., Sainlot N., Samaniego P., Bernard B., Nauret F., Hidalgo S., Auclair D., Gannoun A.M. (2023). Arc volcano activity driven by small-scale metasomatism of the magma source. Nature Geoscience vol.16, p.363-370, - DOI:10.1038/s41561-023-01143-0 - .
- Weinberg R., Moyen J.F., Yi J.K, Zhu D., Chen S., Wang Q. (2023). Using zircons to disentangle back-veining and hybridization of diorite dykes : an example from the Gangdese Arc, Tibet. Journal of Petrology egad010, - DOI:10.1093/petrology/egad010 - .
- Weiss D., Harpp K.S., Harrison L.N., Boyet M., Chauvel C., Farnetani C.G., Finlayson V.A., Lee K.K.M., Parai R., Shahar A., Williamson N.M.B. (2023). Earth’s mantle composition revealed by mantle plumes. Nature Reviews Earth & Environment vol.4, p.604-625, - DOI:10.1038/s43017-023-00467-0 - .
- Werle M., Stevens G., Moyen J.F., Laurent O., Harris C., Lana C.C, Janney P.E. (2023). Cryptic crustal growth identified through Variscan post-collisional lamprophyre-granite composite dykes, French Massif Central. Lithos vol.454-455, p.107270, - DOI:10.1016/j.lithos.2023.107270 - .
- Source, genèse et chronologie des magmas