Past natural changes in Trace elements, Rare Earth Elements (REE), mercury and lead isotopes in the EPICA/Dome C ice core (East Antarctica) from 263,000 to 671,000 yrs BP

• Main Author: Marteel, Alexandrine
• Other Authors: Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-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 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 I, Claude Boutron([e-mail]), C'est une thèse en co-tutelle avec l'Université de Sienne, Italie et l'Université Ca Foscari de Venise, Italie. Collaboration avec l'Université de Technologie, Perth, Australie.
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: HAL CCSD 2007
• Subjects: ice cores; Antarctica; heavy metals; Rare Earth Elements; lead isotopes; mercury; climate; TIMS; carottes de glace; Antarctique; métaux lourds; terres rares; isotopes du plomb; mercure; climat; ICP-SFMS; ICP-QMS; [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology; Antarctic; East Antarctica; Antarc*; Antarctique*; EPICA; ice core
• Online Access: https://tel.archives-ouvertes.fr/tel-00223892; https://tel.archives-ouvertes.fr/tel-00223892/document; https://tel.archives-ouvertes.fr/tel-00223892/file/these_en_entier-english_corrected.pdf

The study of climate necessarily involves the collection and processing of large amounts of data gathered from polar ice cores which are an excellent way of finding how the climate has changed. In this context, I provide the longest records of crustal elements, metals, metalloids, rare earth elements, lead isotopes and mercury taking advantage of the 3270m EPICA/Dome C ice core located in East Antarctica. These elements have been studied in various sections of the EPICA/Dome C deep ice core from 263 ky to 671 ky BP. For crustal elements, metals, metalloids, rare earth elements and mercury, the analyses were performed by Inductively Coupled Plasma Sector Field Mass Spectrometry whilst the analyses of lead isotopes were performed by Thermal Ionization Mass Spectrometry and the analyses of mercury species (methylmercury and inorganic mercury) by Inductively Coupled Plasma Time of Flight Sector Field Mass Spectrometry, in clean room conditions. The study of crustal trace elements (V, Cr, Mn, Fe, Co, Rb, Ba and U) allowed to document large natural variations in the occurrence of several crust derived elements in Antarctic ice from 263 to 671 ky BP. I show that the concentrations were highly variable, with low values during warm periods (interglacials) and much higher values during the coldest stages (glacial maxima). The advection of crustal trace elements to the East Antarctic plateau is found to occur when a well-defined critical δD value (~ - 430‰) was reached. For the first time, the rare earth elements (REE) were analyzed in a deep ice core. The REE of continental origin windblown to the East Antarctica have been studied for their geographical provenance during this time period. In this way, crustal trace elements provenance in glacial and interglacials epochs has been identified through the rare earth elements signature and sediments from Potential Source Areas (PSA) of the Southern Hemisphere. During less pronounced glacial maxima (MIS 12.2, 12.4 and 14.2) at Dome C in East Antarctica, REE show that dust ...