Paleo-erosion rates in Central Asia since 9 Ma: A transient increase at the onset of Quaternary glaciations?
2011
Charreau, Julien | Blard, P.-H. | Puchol, N. | Avouac, Jean-Philippe | Lallier-Vergès, Elisabeth | Bourles, D. | Braucher, Regis | Gallaud, Audrey | Finkel, R. | Jolivet, Marc | Chen, Yan | Roy, Pascal | Centre de Recherches Pétrographiques et Géochimiques (CRPG) ; Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS) | Tectonics Observatory ; California Institute of Technology (CALTECH) | Institut des Sciences de la Terre d'Orléans (ISTO) ; Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS) | Centre Européen de Recherche et d'Enseignement des Géosciences de l'Environnement (CEREGE) ; Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) | Department of Earth and Planetary Science [UC Berkeley] (EPS) ; University of California [Berkeley] (UC Berkeley) ; University of California (UC)-University of California (UC) | Terre, Temps, Traçage ; Géosciences Rennes (GR) ; Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre Armoricain de Recherches en Environnement-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre Armoricain de Recherches en Environnement-Centre National de la Recherche Scientifique (CNRS) | French INSU/CNRS programs SYSTER
International audience
اظهر المزيد [+] اقل [-]إنجليزي. Erosion is a fundamental player of the interactions existing between internal geodynamics and climate, in particular through its influence on the carbon dioxide budget. However, long term (> 1 Ma) erosion rates, estimated indirectly from sediment budget, remain poorly constrained. While some studies suggest that worldwide erosion rates increased at the Plio-Pleistocene climatic transition (~ 4-2 Ma), the validity of this observation and its significance is a matter of debate due to potential biases of the sedimentary record and to the influence of sea level fall on the global sedimentary flux to marginal basins. In the present study, we estimate erosion rates over the last ~ 9 Ma using in situ produced cosmogenic 10Be concentrations measured in magnetostratigraphically dated continental sediments. We focus on an intracontinental endorheic watershed draining the northern Tianshan in Central Asia, a key region regarding the ongoing debate. While erosion rates between 0.1 and 1 mm*yr− 1 are derived from most of our record, they reach values as high as ~ 2.5 mm*yr− 1 from 2.5 to 1.7 Ma. Then, after 1.7 Ma, recent and modern erosion rates fell below 1 mm*yr− 1. This temporary increase is correlated with the onset of Quaternary ice ages and suggests that global climate had a significant and transient impact on erosion.
اظهر المزيد [+] اقل [-]الكلمات المفتاحية الخاصة بالمكنز الزراعي (أجروفوك)
المعلومات البيبليوغرافية
تم تزويد هذا السجل من قبل Institut national de la recherche agronomique