国家重点基础研究发展计划(973)项目“白垩纪地球表层系统重大地质事件与温室气候变化”,将以白垩纪与碳循环相关的重大地质事件和温室气候变化的关系为主线,以大洋缺氧事件一富氧作用转变过程和机制研究为突破口,进行海陆相整合研究,重点追溯东特提斯洋和我国大陆地球表层系统重大地质事件的记录,探讨这些事件与碳循环、快速气候变化的正/负反馈机制。项目将充分利用中国大陆发育完好的白垩纪海相、陆相地层及古生物记录,通过松辽盆地白垩系科学钻探全岩芯取样和多学科综合研究的途径,着眼于厘定反映地质事件和气候变化的层位及标志和时间格架,解决高分辨率海、陆相沉积事件的精确对比,分析地层记录中气候标志和古生物类群的地理分布,集中研究陆地和海洋环境对同一事件的响应机制,重溯白垩纪地球表层系统重大地质事件过程及成因,探究陆相烃源岩大规模形成、陆地生物群更替与温室气候变化和碳循环之间的正/负反馈关系和机制等科学问题,为预测全球长时间尺度上的气候变化趋势提供科学依据。
With the relationship of major geological events related to the carbon cycle and greenhouse climate change as the critical scientific issue, and with transitional process and mechanism from OAE to enhanced oxic effect as the breakthrough point, in our project, we conduct an ocean-land combination research, put emphasis on ascending the major geological events records of Cretaceous Earth Surface System in eastern Tethys ocean and mainland of China, and explore the positive and negative feedbacks among geological events, carbon cycle and rapid climate change. The project will make full use of Cretaceous marine, terrestrial strata and paleontological records. A scientific drilhng core will be conducted in the Songliao basin with about 2000 m in depth full core recovery. This will allow high precision resolution in the correlation of marine and ocean events and facilitate our understanding of environmental and paleoclimatic controls on the geographical distribution of biota. Continental and oceanic response to the same event will be studied to re-construct the processes and reasons of major geological events in the Cretaceous earth surface system, and to explore the mechanisms among genesis of large terrestrial hydrocarbon source rock, terrestrial biota radiation and evolution, greenhouse climate change, carbon cycle, which will give scientific evidences for predicting future trends of long time scale climate change.