华南不同相区早三叠世史密斯-斯帕斯界线事件过程中海洋碳-硫循环及其对事件的响应

史密斯-斯帕斯界线事件是早三叠世最显著的一次生物、环境与气候事件，是探讨二叠纪末生物大灭绝后地球环境和生物协同演变过程的重要研究对象。目前国内外针对该事件的研究尚在起步阶段，事件过程中海洋环境变化的具体过程以及其与生物演化和气候变化的耦合关系仍不清楚。本项目拟在华南不同相区系统开展下三叠统史密斯-斯帕斯界线事件的研究。在研究程度较高的湖北利川、贵州青岩、贵州甲戎和安徽巢湖平顶山等下三叠统剖面中的史密斯-斯帕斯界线附近进行高分辨率的全岩样品采集。选取受成岩改造较小且较“纯净”的碳酸盐岩开展无机碳同位素和碳酸盐晶格硫同位素的测试分析研究，结合前人已发表的数据，重建华南不同相区史密斯-斯帕斯界线事件过程中碳-硫同位素演化曲线、海洋碳-硫循环模式，探讨海洋环流的时间、过程及幅度；揭示海洋环境变化对早三叠世生物复苏的影响及其生物与环境耦合关系。为早三叠世生物复苏机制的研究提供更多新的地球化学信息。

The Smithian-Spathian boundary Event is the most significant biological, environmental and climatic event in the Early Triassic, thus important for the studies of the co-evolutions between environmental changes and biological evolution after the end-Permian mass extinction. However, studies around the event is still lacking to date, and properties of the marine environmental changes and their relationships to the biological and climatic changes is still unclear. Our proposed study aims to investigate the Smithian-Spathian boundary Event at different sedimentary facies in South China. Firstly, sampling in high resulution at several relatively better studied Smithian-Spathian boundary sections (e.g., Lichuan, Hubei; Qingyan, Guizhou; Jiarong, Guizhou; West Pingdingshan, Chaohu) in South China. Better preserved samples were chosen and analyses of the inorganic carbon (δ13Ccarb) and sulfur isotope of carbonate associated sulfate (δ34SCAS) were carried out. Then, we reconstructed δ13Ccarb-δ34SCAS profiles of different sedimentary facies coupled with previous published geochemical data, and discussed carbon-sulfur cycling models during the Smithian-Spathian boundary Event. The timing, processes and amplitudes of marine circulation were discussed. We also discussed the reaction of environmental changes to the biological evolution, and coupling relationship between biology and environment. The present work will provide critical geochemical information for the studies of the mechanisms of the biological recovery during the Early Triassic.