Lake highstands on the Altiplano (Tropical Andes) contemporaneous with Heinrich 1 and the Younger Dryas: new insights from C-14, U-Th dating and delta O-18 of carbonates

• Published in: Quaternary Science Reviews
• Main Authors: Blard, P. -H., Sylvestre, F., Tripati, A. K., Claude, C., Causse, C., Coudrain, A., Condom, T., Seidel, J. -L., Vimeux, F., Moreau, C., Dumoulin, J. -P., Lave, J.
• Other Authors: Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Laboratoire de mesure du carbone 14 (LMC14 - UMS 2572), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2011
• Subjects: [SDU.STU]Sciences of the Universe [physics]/Earth Sciences; Greenland; The Altiplano; North Atlantic
• Online Access: https://hal.archives-ouvertes.fr/hal-01795357; https://doi.org/10.1016/j.quascirev.2011.11.001

International audience This study provides new geochronological and stable isotope constraints on Late Pleistocene fluctuations in lake level that occurred in the closed-watershed of the Central Altiplano between similar to 25 and similar to 12 ka. U-series isochrons and C-14 ages from carbonates are used to confirm and refine the previous chronology published (Placzek et al., 2006b). Our new data support three successive lake highstands during the Late Pleistocene: (i) the lake Sajsi cycle, from similar to 25 to 19 ka, that culminated at 3670 m at about 22 ka, almost synchronously with the global last glacial maximum, (ii) the Lake Tauca cycle, that lasted from 18 to 14.5 ka and was characterized by the highest water level, reached at least 3770 m from 16.5 to 15 ka, (iii) the Lake Coipasa cycle, from 12.5 to 11.9 ka, that reached an elevation of similar to 3700 m, 42 m above the elevation of the Salar de Uyuni (3658 m). These high amplitude lake level fluctuations are in phase with the cold-warm oscillations that occurred in the North Atlantic and Greenland during the Late Pleistocene (Heinrich 1, Bolling-Allerod, Younger Dryas). Such temporal coincidence supports the hypothesis that wet events recorded in the Central Altiplano are controlled by the north-south displacement of the Inter Tropical Convergence Zone resulting from changes in the meridional temperature gradient. Finally, the oxygen isotope ratios measured in these lacustrine carbonates allows for calculation of the delta O-18 value of paleolake waters. Estimates of water delta O-18 (V-SMOW) are -2.8 +/- 0.7 parts per thousand for Lake Tauca and -1.6 +/- 0.9 parts per thousand, for Lake Coipasa. These data are used to constrain changes in lake hydrology and can be interpreted to indicate that the proportion of precipitation arising from local water recycling was less than 50%. (C) 2011 Elsevier Ltd. All rights reserved.