青藏高原新生代湖相碳酸盐岩碳氧同位素特征与古环境意义

青藏高原新生代构造隆升不仅造就了亚洲古地形格局的改变，同时对亚洲甚至全球气候变化产生重大影响。青藏高原腹地是直接感应高原隆升过程环境变化效应的核心地带，目前地学界对其环境格局演变的时空特点和区域分异过程仍缺乏深入认识。原生湖相碳酸盐岩与区域环境变化关系密切，它的碳、氧同位素特征及组合是研究古环境和古气候变化的重要指标。研究工作拟以青藏高原尼玛盆地、可可西里盆地和柴达木盆地广泛分布的新生代湖相碳酸盐岩沉积作为主要研究对象，利用原生湖相碳酸盐岩碳、氧同位素信息作为古水文、古温度和古盐度等环境变化的替代指标，开展湖相碳酸盐岩地层剖面的高分辨率碳、氧同位素变化信息的研究，聚焦新生代冷暖、干湿气候环境演变历史，构建以青藏高原为中心的重大环境变革事件的时空坐标，为探索中国新生代区域环境分异、亚洲季风起源、全球气候变冷的耦合关系提供对比框架。

The Cenozoic tectonic uplift of the Tibetan Plateau not only resulted in the variation of the Asian paleotopographic pattern, but also led to the complete change of the global climate pattern. The hinterland of the Tibetan Plateau is a direct response to environmental change in the course of the uplift of the Tibetan Plateau, however, the geologists still lack a deep understanding in the spatial and temporal characteristics and regional differentiation of its environmental pattern evolution. Primary lacustrine carbonate deposits are closely associated with regional environmental variation, of which carbon and oxygen isotope characteristics and assemblages are important proxies for studying paleoenvironmental and paleoclimatic change. Therefore, the Cenozoic lacustrine carbonate deposits widely distributed in the Tibetan Plateau is taken as the main research subject in the study. Carbon and oxygen isotope information of primary lacustrine carbonate is used as alternative indicators of paleohydrology, paleotemperature and paleosalinity. High-resolution carbon and oxygen isotope variation information on typical sedimentary profiles of the Cenozoic lacustrine carbonate in the Nima, Hoh Xil and Qaidam Basins of the plateau hinterland is the key to studying the climate evolution history of cold and warm, dry and wet in the Cenozoic. In addition, based on the spatial and temporal coordinates of major environmental change events centered on the Tibetan Plateau, this study provides a comparative framework for exploring the coupling relationship between Cenozoic regional environmental differentiation in China, the origin of Asian monsoon and global climate cooling.