Middle to Late Miocene Eccentricity Forcing on Lake Expansion in NE Tibet

• Published in: Geophysical Research Letters
• Main Authors: Wang, Zhixiang, Huang, Chunju, Licht, Alexis, Zhang, Rui, Kemp, David, B
• Other Authors: China University of Geosciences Wuhan (CUG), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-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)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2019
• Subjects: [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy; Antarctic; Antarc*; Ice Sheet
• Online Access: https://hal.science/hal-03469361; https://hal.science/hal-03469361/document; https://hal.science/hal-03469361/file/Wang%20et%20al%202019%20JGR.pdf; https://doi.org/10.1029/2019gl082283

International audience The East Asian summer monsoon (EASM) variability on orbital time scale has been extensively investigated in Quaternary loess and speleothems. However, EASM variability during pre-Quaternary time remains poorly understood. Here we report a continuous upper Miocene cyclostratigraphic record from lake deposits of the Tianshui basin, Northeast Tibet, to reconstruct past variations of the regional hydrological cycle. Our results, combined with previously published cyclostratigraphic records from Northeast Tibet, show that regional lake expansion cycles have been consistently dominated by~100-kyr eccentricity forcing over most of the middle to late Miocene. These~100 kyr cycles corroborate a significant forcing of the East Asian hydrological cycle by Antarctic ice sheet variations at that time. It is, however, unclear if this forcing affected EASM intensity or westerly derived moisture supply to the far east. Regardless of the nature of the main source of precipitation in Northeast Tibet during the Miocene, these results emphasize the existence of a strong teleconnection between Antarctic ice sheet modulations and the continental climate of Asia.