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1. Effects of oxidative weathering on Raman spectra of charcoal and bone chars: consequences in archaeology and paleothermometry

Author

Deldicque, Damien, Rouzaud, Jean-Noël, Vandevelde, Ségolène, Medina-Alcaide, Maria Ángeles, Ferrier, Catherine, Perrenoud, Christian, Pozzi, Jean-Pierre, and Cabanis, Manon

Subjects
Raman spectrometry, Oxidative weathering, Charcoal, Animal chars, Charred bone, Archaeology, Pyroclastic flow, Geophysics. Cosmic physics, QC801-809, Chemistry, QD1-999, Geology, QE1-996.5
Abstract

Chars are useful proxies in many disciplines such as the geosciences and archaeology. Raman spectrometry is frequently used in the characterization of such materials. However, when they are ancient and potentially altered, chars have the particularity of being oxidized, which can strongly disturb the spectra and seriously distort their interpretation. In this study, we highlight the Raman parameters affected by oxidative weathering based on comparisons between the spectra of experimental and ancient chars, of vegetal and animal origin. This makes it possible to differentiate between unweathered and weathered chars and we show that the recent methods of Raman thermometry and precursor discrimination are no longer valid when applied to oxidized chars. Nonetheless, it remains possible to estimate the formation temperature of a charcoal when some fragments are preserved at the micrometre scale. Furthermore, we propose an original tool that enable us to distinguish the vegetal or animal origin of ancient and oxidized chars. We successfully apply this new tool to charred hearth residues of the Bruniquel cave (France).

Published
2023
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2. Traces of fire in a 560,000-year-old occupation soil at Caune de l’Arago: response to the article by Professor Henry de Lumley

Author

Deldicque, Damien, Pozzi, Jean-Pierre, Perrenoud, Christian, Falguères, Christophe, Mahieux, Geoffroy, Lartigot-Campin, Anne-Sophie, and Rouzaud, Jean-Noël

Subjects
charcoal, Caune de l’Arago cave, Magnetic susceptibility, Raman spectroscopy, Fire, Middle Pleistocene, Magnetic minerals, Geophysics. Cosmic physics, QC801-809, Chemistry, QD1-999, Geology, QE1-996.5
Abstract

This note is a reply to the comment “Did the first inhabitants of the Caune de l’Arago between 700,000 and 400,000 years BP have domesticated fire? Did they know how to light the fire at will?” by H. de Lumley, published in Comptes Rendus Géoscience in Volume 354, 2022, pages 41-45, https://doi.org/10.5802/crgeos.113. The comment in question concerns the article “Search for early traces of fire in the Caune de l’Arago at Tautavel (Eastern Pyrenees, France), combining magnetic susceptibility measurements, microscopic observations, and Raman analysis” by Deldicque et al., published online on July 29, 2021, in Comptes Rendus Géoscience in Volume 353, 2021, pages 247-264, https://doi.org/10.5802/crgeos.66.

Published
2022
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3. Search for early traces of fire in the Caune de l’Arago at Tautavel (Eastern Pyrenees, France), combining magnetic susceptibility measurements, microscopic observations, and Raman analysis

Author

Deldicque, Damien, Pozzi, Jean-Pierre, Perrenoud, Christian, Falguères, Christophe, Mahieux, Geoffroy, Lartigot-Campin, Anne-Sophie, and Rouzaud, Jean-Noël

Subjects
Middle Pleistocene, Caune de l’Arago cave, Fire, Charcoal, Magnetic susceptibility, Raman spectroscopy, Magnetic minerals, Geophysics. Cosmic physics, QC801-809, Chemistry, QD1-999, Geology, QE1-996.5
Abstract

The Caune de l’Arago is an important Middle Pleistocene archaeological site, consisting of a cave with a sedimentary infilling deposited between 700 and 100 ka. Excavations have revealed traces of the use of fire in the layers formed between 400 and 100 ka, but no earlier traces have been recorded in the underlying levels. These potential older traces may have undergone various processes of weathering, and could have been degraded or considered nonexistent. This study combines magnetic susceptibility measurements, microscopic examination, Raman analyses, and elemental analyses by scanning electron microscopy to look for traces of fire activity such as combustion residues preserved among the sediments. This approach has led to the discovery of a zone in the Q4 level, whose age is estimated at 560 ka, which is rich in magnetic minerals and charcoal. The anthropic or natural origin of these materials is discussed.

Published
2021
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8. A Magnetic Geothermometer in Moderately Buried Shales

Author

Aubourg, Charles, Kars, Myriam, Pozzi, Jean-Pierre, Mazurek, Martin, Grauby, Olivier, Laboratoire des Fluides Complexes et leurs Réservoirs (LFCR), TOTAL FINA ELF-Université de Pau et des Pays de l'Adour (UPPA)-Centre National de la Recherche Scientifique (CNRS), Kochi University, Université Paris sciences et lettres (PSL), University of Bern, Centre Interdisciplinaire de Nanoscience de Marseille (CINaM), and Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
oil window, magnetite, [SDU]Sciences of the Universe [physics], 550 Earth sciences & geology, goethite, geothermometer, Mineralogy, shales, QE351-399.2
Abstract

Shales contain magnetic minerals generally at very low concentrations. In the early stages of diagenesis, the inherited magnetic minerals are altered, while magnetic nanominerals are formed. In this study, we proposed a study of shales over a stratigraphic thickness of 1.3 km from a borehole in the Paris basin (Borehole EST 433, France), and shales from the same formation (Opalinus Clay) collected in seven boreholes in the Jura molasse basin (Swiss). Magnetic measurements at experimental temperatures &lt, 30 K allowed the formation of a proxy of magnetite nanograins named PM. We showed that some of these nanograins formed around the pyrite grains, probably under the action of temperature and organic matter. PM was then compared to the maturity values of the organic matter. We found a correlation between PM and the percentage of reflectance of vitrinite. The shales from both Paris and molassic Swiss basins showed very comparable magnetic characteristics for a given maturity level. The magnetic study therefore provided constraints on the maturity level of the shales in the oil window area. Our study showed that PM can be used as a geothermometer in shales in which CaCO3 is lower than 60%.

Published
2021
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9. Magnetic monitoring of hydrothermal magnetite nucleation-and-growth: record of magnetic reversals

Author

Cairanne, Guillaume, Brunet, Fabrice, Pozzi, Jean-Pierre, Besson, Pascale, and Aubourg, Charly

Subjects
Magnetite -- Research, Earth sciences
Abstract

Hematite reduction in the presence of pyrite and CaO led to the formation of anhydrite and magnetite at 30 MPa and 723 K under hydrothermal conditions in a sealed gold container. For the first time, hydrothermal magnetite production was monitored magnetically at the run conditions. Sample magnetic susceptibility was found to follow an Avrami kinetic law with k = 1.5 [10.sup.-5]/s and n = 2.07. Application of up to two external field reversals in the course of the magnetite production reaction shows that partial Chemical Remanent Magnetizations (CRM) are recorded by the sample. The intensity of each partial CRM acquired within a given time interval (under a given field intensity) is proportional to the amount of magnetite produced during that time interval. Alternating magnetic field demagnetization failed at separating these partial CRMs, which are believed to superpose in the (V, Hc) diagram of Neel. Additional TEM, SEM, and magnetic characterizations suggest that continuous nucleation and fast magnetite growth (to a maximum size of ca. 10 [micro]m), compared to the field polarity duration, can account for the evolution of the sample CRM with time. This study demonstrates that one should be cautious when using natural CRM apparent polarity to infer timing of the corresponding chemical event.

Published
2003

10. Chronologie et enregistrements climatiques dans les dépôts travertineux du Maroc

Author

Rousseau , Louis, Falguères, Christophe, Pozzi, Jean-Pierre, Weisrock, André, Ghaleb, Bassam, Mahieux, Geoffroy, Beauchamp, Jacques, Ouammou, Abderrahmane, Haddad, Mustapha, Bejjit, Lahcen, Charif, Abdessamad, Lauriol, Bernard, Histoire naturelle de l'Homme préhistorique (HNHP), and Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)-Université de Perpignan Via Domitia (UPVD)

Subjects
[SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2017

11. Un gisement sparnacien exceptionnel à plantes, arthropodes et vertébrés (Éocène basal, MP7): Le Quesnoy (Oise, France)

Author

Nel, André, de Plöeg, Gaël, Dejax, Jean, Dutheil, Didier, de Franceschi, Dario, Gheerbrant, Emmanuel, Godinot, Marc, Hervet, Sophie, Menier, Jean-Jacques, Augé, Marc, Bignot, Gérard, Cavagnetto, Carla, Duffaud, Sylvain, Gaudant, Jean, Hua, Stéphane, Jpssang, Akino, de Lapparent de Broin, France, Pozzi, Jean-Pierre, Paicheler, Jean-Claude, Beuchet, Françoise, and Rage, Jean-Claude

Published
1999
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13. Low temperature magnetic behaviour near 35 K in unmetamorphosed claystones

Author

Kars, Myriam, Aubourg, Charles, Pozzi, Jean-Pierre, Laboratoire des Fluides Complexes et leurs Réservoirs (LFCR), TOTAL FINA ELF-Université de Pau et des Pays de l'Adour (UPPA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de géologie de l'ENS (LGE), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris)-École normale supérieure - Paris (ENS Paris), Centre National de la Recherche Scientifique (CNRS)-Université de Pau et des Pays de l'Adour (UPPA)-TOTAL FINA ELF, Laboratoire de géologie de l'ENS (LGENS), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), and Urrea, Catherine

Subjects
[PHYS]Physics [physics], Rock and mineral magnetism, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], Phase transitions, [SDU.STU.GP] Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], Magnetic and electrical properties, [PHYS] Physics [physics]
Abstract

International audience; There is growing evidence that the magnetic assemblage of claystones, illustrated by low-temperature magnetic transitions at ~120 K and ~35 K, may be representative of the peak burial temperature in the so-called oil-window (60-150°C). In previous studies, it was proposed that this magnetic assemblage is characterized by fine-grained pyrrhotite (Fe7S8) and magnetite (Fe3O4). However, evidence of pyrrhotite was not so obvious and the magnetic transition near 35 K of fine-grained pyrrhotite has similarities with those of siderite (FeCO3) or rhodochrosite (MnCO3). Here, we propose some diagnostic tests to distinct

Published
2011

14. CHRONOSTRATIGRAPHIE DE TRAVERTINS DE PLUSIEURS RÉGIONS DU MAROC ET LEURS RELATIONS AVEC LE CONTEXTE PALÉOCLIMATIQUE GLOBAL

Author

Rousseau, Louis, Aouraghe, Hassan, Bahain, Jean-Jacques, Beauchamp, Jacques, Benabdelhadi, Mohamed, Boudad, Larbi, Elhammouti, Kamal, El Harradji, Abderrahmane, Falguères, Christophe, Nicot, Elisabeth, Pozzi, Jean-Pierre, Weisrock, André, Histoire naturelle de l'Homme préhistorique (HNHP), Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Sédimentologie et de Géochimie, Université de Picardie Jules Verne (UPJV), Faculté des Sciences, Centre Universitaire de Recherches en Archéologie, Université Mohamed I Faculté des Sciences, Faculté des Sciences et Techniques, Université Sidi Mohamed Ben Abdellah (USMBA), Faculté des Sciences et techniques, Université de Moulay Ismail (UMI), Laboratoire de Stratigraphie et de Paléontologie, Université Pierre et Marie Curie - Paris 6 (UPMC), Laboratoire de géologie de l'ENS (LGE), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris)-École normale supérieure - Paris (ENS Paris), Centre d'Etudes et de Recherche sur les Paysages (CERPA), Université Nancy 2, Université Moulay Ismail (UMI), Paléontologie et stratigraphie (URA 1761 / ESA 7073 / FRE 2400), Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de géologie de l'ENS (LGENS), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), École normale supérieure - Paris (ENS-PSL), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL)

Subjects
Maroc, Travertines, Morocco, Radiochronology, Radiochronologie, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, Uranium series dating, Travertins, Isotopic stage, [SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology, Stades isotopiques, Méthode U/Th par spectrométrie alpha, TIMS
Abstract

We studied here travertines of Eastern Morocco. For this part of Africa, these concretions indicate ancient humidphases which are suspected to be linked with palaeo-monsoons and the precession cycle of 23,000 yrs. Ourprincipal aim is to precise the planetary configuration which is associated with the climatic conditions of theirconstruction and to determine the chronological frequency of the travertine deposits. In fact, travertines, likespeleothems, can be regarded as valuable archives of climatic conditions on the continent. The major differenceis that the formation of the speleothems is generally discontinuous and all the isotopic stages are not recorded,while the travertines are continuously recorded at least travertine sequences are very thicken and can cover hugegeological periods. However, erosion could unfortunately suppress a part of climatic information. The preliminary results show that in order to find the precession cycles of 23 000 yrs and to obtain a weak uncertainty for the periods comprised between 500,000 and 100,000 yrs., the development of mass-spectrometry by ICP-MS should to be used.; Les travertins sont abondants au Maroc oriental, et correspondent à des formations largement développées auniveau des sources et des cascades au cours du Quaternaire. Les formations travertineuses soumises ici aux analyses radiochronologiques sont réparties dans différentes régions du Maroc (Errachidia, Lalla Mimouna,Debdou et Fès). On tente ainsi de définir le synchronisme des changements climatiques à une échelle continentale régionale et d'associer les périodes de forte humidité responsables des dépôts de travertins à des « paléo-moussons » issues de changements climatiques globaux, le terme « paléo-mousson » étant utilisé dans le sens anglo-saxon qui évoque le déplacement de masses d'air océanique vers le continent. Les travertins sont susceptibles d'avoir un enregistrement plus complet que ceux enregistrés dans les planchers stalagmitiques, maisl'érosion peut en supprimer une partie. Les résultats préliminaires montrent que pour essayer de retrouver descycles de précession de 23.000 ans responsables de ces paléo-moussons avec de faibles incertitudes durant lespériodes comprises entre 500.000 et 100.000 ans, la spectrométrie de masse (TIMS ou ICP-MS) devra êtreutilisée.

Published
2008

15. First results of an radiochronological study of Imouzzer Ida ou Tanane travertines, Morocco

Author

Rousseau, Louis, Weisrock, André, Falguères, Christophe, Bahain, Jean-Jacques, Beauchamp, Jacques, Pozzi, Jean-Pierre, Ghaleb, Bassam, Mahieux, Geoffroy, Boudad, Larbi, Bejjit, Lahcen, Bouajaja, Mohamed, Haddad, Mustapha, Janati-Idrissi, Nouha, Ouammou, Abderrahmane, Histoire naturelle de l'Homme préhistorique (HNHP), Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Sédimentologie et de Géochimie, Université de Picardie Jules Verne (UPJV), Centre d'Etudes et de Recherche sur les Paysages (CERPA), Université Nancy 2, Laboratoire de géologie de l'ENS (LGE), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris)-École normale supérieure - Paris (ENS Paris), Centre de recherche sur la dynamique du système Terre (GEOTOP), École Polytechnique de Montréal (EPM)-Université McGill -Université de Montréal (UdeM)-Université du Québec en Abitibi-Témiscamingue (UQAT)-Université du Québec à Rimouski (UQAR)-Concordia University [Montreal]-Université du Québec à Montréal (UQAM), Faculté des Sciences et Techniques, Géologie, Université de Moulay Ismail (UMI), Faculté des Sciences (LASMAR), Faculté des Lettres et Sciences Humaines, Université Ibn Zohr [Agadir], Laboratoire de géologie de l'ENS (LGENS), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Université de Montréal (UdeM)-McGill University = Université McGill [Montréal, Canada]-École Polytechnique de Montréal (EPM)-Concordia University [Montreal]-Université du Québec à Rimouski (UQAR)-Université du Québec à Montréal = University of Québec in Montréal (UQAM)-Université du Québec en Abitibi-Témiscamingue (UQAT), and Université Moulay Ismail (UMI)

Subjects
Quaternary, Maroc, Travertines, Morocco, Datations, Aimantation, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, Travertins, U/Th-TIMS, MIS, Stades isotopiques, Magnetization, Quaternaire
Abstract

The well-known travertines of the Imouzzer Ida Ou Tanane great waterfall, lying to-day under a semi-arid climateand high anthropic erosional conditions, are for the first time dated by the U/Th-TIMS method. The preliminaryresults give 5 dates at 434,3 + 97,5 – 52,8 ky, 296,6 + 16,4 – 14,5 ky, 48,4 ± 0,7 ky, 36,1 ±1 ky, 15,4 ± 0,3 ky BP,and allowed to recognize at least 4 main periods of travertine aggradation during the MIS 12 (?) or more, MIS 9 or 8, 3 and 2. During MIS 9, 7, 5, 4 and the LGM, phases of deep fluvial linear, non-anthropic incision occurred, mainlyduring MIS 5 and the LGM. These results are consistent with the surrounding Late Quaternary evolution (Weisrock& al., 2006) and previous results of other travertines of Morocco (Rousseau & al., 2006).; Les travertins bien connus des grandes cascades d'Imouzzer Ida Ou Tanane, aujourd'hui soumis à un climat semi aride et à une forte érosion anthropique, sont datés pour la première fois par la méthode U/Th-TIMS. Les résultats préliminaires donnent 5 dates à 434,3 + 97,5 – 52,8 ka, 296,6 + 16,4 – 14,5 ka, 48,4 ± 0,7 ka, 36,1 ± 1 ka, 15,4 ± 0,3, ka BP., et permettent de reconnaître au moins 4 grandes périodes de travertinisation durant les stades isotopiques 12 ( ?) ou plus, 9 ou 8, 3 et 2. Durant les stages 9, 7, 5, 4 et le dernier maximum glaciaire, des périodes de profonde incision fluviatile non anthropiques sont intervenues, particulièrement lors du stade 5 et durant le dernier maximum glaciaire. Ces résultats sont en accord avec l'évolution quaternaire récente des régions voisines (Weisrock & al., 2006) et des résultats obtenus auparavant sur d'autres travertins du Maroc (Rousseau & al., 2006).

Published
2008

16. First laboratory measurements of seismo-magnetic conversions in fluid-filled Fontainebleau sand

Author

Bordes, Clarisse, Jouniaux, Laurence, Dietrich, Michel, Pozzi, Jean-Pierre, Garambois, Stéphane, Modélisation et Imagerie en Géosciences - Pau (MIGP), Centre National de la Recherche Scientifique (CNRS)-Université de Pau et des Pays de l'Adour (UPPA)-TotalFinaElf-Institut national des sciences de l'Univers (INSU - CNRS), GE, Institut de physique du globe de Strasbourg (IPGS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Géophysique Interne et Tectonophysique (LGIT), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Laboratoire Central des Ponts et Chaussées (LCPC)-Institut des Sciences de la Terre (ISTerre), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR), Laboratoire de géologie de l'ENS (LGE), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris)-École normale supérieure - Paris (ENS Paris), CNRS, French Ministry of Research : ACI Eau et environnement, LSBB, Institut national des sciences de l'Univers (INSU - CNRS)-TotalFinaElf-Université de Pau et des Pays de l'Adour (UPPA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Central des Ponts et Chaussées (LCPC)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de géologie de l'ENS (LGENS), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Laboratoire de Modélisation et d'Imagerie en Géosciences de Pau (MIGP), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Laboratoire Central des Ponts et Chaussées (LCPC)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS-PSL), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL)

Subjects
magnetic, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], [SDE.MCG]Environmental Sciences/Global Changes, seismomagnetic, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], sand, electric, seismoelectric, Physics::Geophysics, seismoelectromagnetic, Physics::Space Physics, rock physics, [SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology, electrokinetic
Abstract

International audience; Seismic wave propagation in fluid-filled porous materials induces electromagnetic effects due to small relative pore-fluid motions. In order to detect the seismo-magnetic couplings theoretically predicted by Pride (1994), we have designed a small-scale experiment in a low-noise underground laboratory which presents exceptional electromagnetic shielding conditions. Our experiment included accelerometers, electric dipoles and induction magnetometers to characterize the seismo-electromagnetic propagation phenomena. To assess the electrokinetic origin of the measured electric and magneticfields, we compared records obtained in dry and fluid-filled sand. Extra care has been taken to ensure the mechanical decoupling between the sand column and the magnetometers to avoid spurious vibrations of the magnetometers and misinterpretations of the recorded signals. Our results show that seismo-electric and seismo-magnetic signals are associated with different wave propagation modes, thus emphasizing the electrokinetic origin of these effects.

Published
2006
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18. Reconstruction of low temperature (<100 °C) burial in sedimentary basins: A comparison of geothermometer in the intracontinental Paris Basin

Author

Blaise, Thomas, primary, Barbarand, Jocelyn, additional, Kars, Myriam, additional, Ploquin, Florian, additional, Aubourg, Charles, additional, Brigaud, Benjamin, additional, Cathelineau, Michel, additional, El Albani, Abderrazak, additional, Gautheron, Cécile, additional, Izart, Alain, additional, Janots, Dominique, additional, Michels, Raymond, additional, Pagel, Maurice, additional, Pozzi, Jean-Pierre, additional, Boiron, Marie-Christine, additional, and Landrein, Philippe, additional

Published
2014
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19. Streaming potential of a sand column in partial saturations conditions

Author

Guichet, Xavier, Jouniaux, Laurence, Pozzi, Jean-Pierre, Laboratoire de géologie de l'ENS (LGENS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Institut de physique du globe de Strasbourg (IPGS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), CNRS-INSU-PNRH, ACI Prévention des Catastrophes Naturelles, Laboratoire de géologie de l'ENS (LGE), and École normale supérieure - Paris (ENS Paris)-École normale supérieure - Paris (ENS Paris)

Subjects
hydrogéologie, 5139 Physical Properties of Rocks: Transport properties, KEYWORDS: Streaming potential, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], Milieux poreux, streaming potential, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], Géomateriaux, partial saturation, spontaneous potential, porous media, transport properties, 5109 Physical Properties of Rocks: Magnetic and electrical properties, [SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology, Hydrologie, electrokinetic
Abstract

p.2141; The understanding of the streaming potential in partial water saturation conditions in porous media is of great interest for the interpretation of spontaneous polarization observations. We built a device which allows us to quantify the streaming potential at various saturation conditions using a sand column of 1-m height and 8-cm diameter. This is the first time that such a quantification has been performed. Different gases such as argon, nitrogen, and carbon dioxide are injected into the sand to decrease its water saturation, and to make the fluid flow within the sand. The measured electrokinetic coupling coefficient in partial saturation is either constant or decreases by a factor 3 with decreasing water saturation from 100 to 40%, whereas the sand electrical resistivity is enhanced by a factor of 5.

Published
2003
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20. Streaming potential on volcanic samples (solicited paper)

Author

Jouniaux, Laurence, Bernard, Marie-Lise, Zamora, Maria, Pozzi, Jean-Pierre, Institut de physique du globe de Strasbourg (IPGS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL), Laboratoire de Recherche en Géosciences et Energies (LARGE), Université des Antilles (UA), Institut de Physique du Globe de Paris (IPGP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de géologie de l'ENS (LGENS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)

Subjects
[SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], [SDU.STU.VO]Sciences of the Universe [physics]/Earth Sciences/Volcanology, [SDU.STU.PE]Sciences of the Universe [physics]/Earth Sciences/Petrography, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
1998

24. Travertins de la bordure nord du Sahara marocain : dispositifs morphologiques, datations U/Th et indications paléoclimatiques

Author

Weisrock, André, primary, Rousseau, Louis, additional, Reyss, Jean-Louis, additional, Falguères, Christophe, additional, Ghaleb, Bassam, additional, Bahain, Jean-Jacques, additional, Beauchamp, Jacques, additional, Boudad, Larbi, additional, Mercier, Norbert, additional, Mahieux, Geoffroy, additional, Pozzi, Jean-Pierre, additional, Janati-Idrissi, Nouha, additional, and Ouammou, Abderrahmane, additional

Published
2008
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40. Paleomagnetic and plate tectonic constraints on the movement of Tibet

Author

Westphal, Michel and Pozzi, Jean-Pierre

Abstract

The paleomagnetic results from Tibet, north of the Yarlung-Zang bo suture zone, show that Tibet was at about 15°–20°N in Middle Cretaceous time. It then moved south down to 7°–10°N in the Late Cretaceous-Paleogene. The oceanic crust of the Xigaze ophiolites was magnetized at 13°N but thereafter migrated further south. This movement is compared with the relative movement of India and Asia as deduced from magnetic anomalies and paleomagnetism. Experimental models on deformation help us to explain how Tibet moved during the Late Cretaceous under the constraint of the Africa-Arabia indenter and during the Upper Tertiary under the constraint of the Indian indenter.

Published
1983
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