Terrestrial records of the early Albian Ocean Anoxic Event:Evidence from the Fuxin lacustrine basin,NE China

作     者：Xiao-Tao Xu Long-Yi Shao Kenneth A.Eriksson Bo Pang Shuai Wang Cheng-Xue Yang Hai-Hai Hou Xiao-Tao Xu;Long-Yi Shao;Kenneth A.Eriksson;Bo Pang;Shuai Wang;Cheng-Xue Yang;Hai-Hai Hou

作者机构：College of Geoscience and Surveying EngineeringChina University of Mining and Technology(Beijing)Beijing 100083China Shandong Key Laboratory of Depositional Mineralization&Sedimentary MineralShandong University of Science and TechnologyQingdao 266590China Department of GeosciencesVirginia TechBlacksburgVA 24061USA Liaoning Province Geology and Minerals Group Energy Geology Co.Ltd.Shenyang 110000China Institute of Earth SciencesChina University of Geosciences(Beijing)Beijing 100083China College of MiningLiaoning Technical UniversityFuxin 123000China 

出 版 物：《Geoscience Frontiers》 (地学前缘（英文版）)

年 卷 期：2022年第13卷第1期

页      面：138-157页

核心收录：

学科分类：070904[理学-构造地质学] 0709[理学-地质学] 07[理学] 0708[理学-地球物理学] 0704[理学-天文学] 

基　　金：supported by the Yue Qi Scholar Project of China University of Mining and Technology(Beijing)China the National Natural Science Foundation of China(41572090 42002128) Shandong Key Laboratory of Depositional Mineralization&Sedimentary Mineral Shandong University of Science and Technology China(DMSM20190015) 

主　　题：Fuxin Basin Early Albian Organic carbon isotopes Ocean Anoxic Event 1b Terrestrial records 

摘      要：The early Albian Oceanic Anoxic Event 1 b(OAE 1 b) is well documented in the Tethys, Pacific and North Atlantic, but few studies have evaluated whether or not terrestrial records of OAE 1 b exist. In order to identify terrestrial records of the early Albian OAE 1 b and to infer possible driving mechanisms, an integrated multi-proxy study from the late Aptian to Albian in the Fuxin lacustrine basin was conducted,including thick, organic-rich black mudstones, total organic carbon(TOC), organic carbon isotopes(d13 Corg), mercury concentration(Hg) and results from pyrolysis analyses(S2, Tmaxand HI). Results show three distinct short-term negative d13 Corgexcursions corresponding with relatively high TOC values,which could be counterparts of the Kilian, Paquier and Leenhardt sub-events of the early Albian OAE1 b. Atmospheric CO2 concentration(p CO2) recovered from C3 plant d13 Corgcompositions indicates an increasing trend in Unit C during the early Albian, and there are three short-term increases of p CO2 corresponding to the three sub-events of OAE 1 b at this time interval. We infer that a trend of increasing p CO2 during the Kilian sub-event in the study area is closely related to volcanism. Continental weathering calculated using chemical weathering indices(CIA, WIP and MIA(O)) show an increasing trend during the OAE 1 b interval, likely resulting from warmer and more humid conditions. Mixed sources of terrestrial plants and lacustrine plankton demonstrated by pyrolysis analyses(HI vs. Tmaxand S2 vs. TOC), indicate a terrestrial contribution to the organic-rich sediments of the Kilian, Paquier and Leenhardt sub-events of OAE 1 b. We suggest that a CO2-forced greenhouse effect during the early Albian might have triggered the relatively warm and humid palaeoclimatic conditions, and intensified chemical weathering that combined to create high nutrient and organic matter levels that were flushed into lakes contributing to eutrophication and anoxia in lacustrine and in c