南黄海中生代构造体制转换的热史记录及动力学背景

The Mesozoic tectonic regime conversion of the East Asian continental margins has always been a hot research topic in Geosciences for a long time, but the conversion time and its geodynamic mechanism are still controversial. The South Yellow Sea locates in a key area of tectonic interaction among the North China Plate, South China Block and Western Pacific region, and its lithospheric thermal system underwent significant transition during Mesozoic, which provides a new idea for the research of the tectonic regime conversion in East Asia. However, compared with the onshore area in eastern China, the related research on the South Yellow Sea is nearly blank. In addition, as a potential area for hydrocarbon exploration, the reconstruction of tectono-thermal evolution history is also important for petroleum resources evaluation. The CSDP-2 borehole, which is supported by the Continental Scientific Drilling Project (CSDP) and completed at the end of 2016, is the exclusive deep borehole in the central uplift zone of South Yellow Sea. It revealed the integrated stratigraphic sequence from the Quaternary to the Upper Ordovician, with a total depth of 2843m, and the core recovery can reach up to 97.7%, providing a precious opportunity for this research. Based on the previous studies on vitrinite reflectance and fluid inclusions from core samples of CSDP-2 borehole, this project is intended to utilize systematic low-temperature geochronological tests of the zircon and apatite samples, and combine with the method of geodynamic simulation, so as to reconstruct the thermal evolution history of the Mesozoic tectonic regime conversion from convergent extrusion to extensional rifting. Then the characteristics of thermal history which may reflect the processes of tectonic regime conversion can be researched, and its geodynamic background can be further analyzed. Therefore, this project will promote the study of the Mesozoic tectonic regime conversion in East Asian continental margins and lay important foundation for petroleum resources evaluation in South Yellow Sea and the research of regional geodynamics.

东亚陆缘中生代构造体制转换一直是地学研究的热点，但其转换时限及动力学机制仍存争议。南黄海位于华北、华南块体及西太平洋构造域相互作用的关键区，其岩石圈热体制在中生代经历了显著的转换，为研究东亚构造体制转换提供了新的切入点，但与陆域相比，南黄海相关研究几近空白。此外，南黄海作为当前资源调查的潜力区,其油气突破等也亟需热史信息提供参考。大陆架科学钻探CSDP-2全取心井于2016年底完钻，该井是南黄海中部隆起的唯一深钻，完钻井深2843m，取心率高达97.7%，获取了第四系至上奥陶统连续完整的岩心，为本研究提供了绝佳机会。本项拟通过CSDP-2井岩心样品的锆石及磷灰石低温热年代学分析，并结合地球动力学热模拟方法，将盆地尺度的热史恢复与岩石圈尺度的热模拟相结合，耦合重建南黄海中生代从汇聚挤压向伸展型体制转换过程的热演化史，研究其在时间域上的热响应特征，明确构造转换的时限及过程，并分析其动力学背景。

东亚陆缘中生代构造体制转换一直是地学研究的热点，但其转换时限及动力学机制仍存争议。南黄海位于华北、华南块体及西太平洋构造域相互作用的关键区，其岩石圈热体制在中生代经历了显著的转换，为研究东亚构造体制转换提供了新的切入点，但与陆域相比，南黄海相关研究几近空白。此外，南黄海作为当前资源调查的潜力区,其油气突破等也亟需热史信息提供参考。大陆架科学钻探CSDP-2全取心井于2016年底完钻，该井是南黄海中部隆起的唯一深钻，完钻井深2843m，取心率高达97.7%，获取了第四系至上奥陶统的连续完整的岩心，为本研究提供了绝佳机会。. 在本项目资助下，完成了CSDP-2井岩心样品古温标和低温热年代学测试，包括32样次磷灰石及锆石裂变径迹、16样次锆石U-Th/He，31样次镜质体反射率和16样次流体包裹体测试等，分析了南黄海中部隆起中、新生代构造沉降、隆升、剥蚀和岩浆侵入等构造热事件，结合南黄海区域地质、地球物理及钻井资料，重建了印支期以来的热演化历史，揭示了两期主要的降温事件，据此探讨了南黄海中生代构造转换的过程和动力学背景。. 对比了东亚陆缘南黄海中部隆起和大兴安岭的中生代隆升、剥蚀和降温过程，探讨了苏鲁造山带演化、西太平洋俯冲对东亚陆缘构造热演化的影响，发现了晚古新世至始新世的升温事件可能与印度与亚洲碰撞的远场效应，以及古太平洋俯冲导致的岩石圈热结构变化和岩浆活动有关。在此基础上，研究了南黄海中部隆起中、新生代构造热事件对烃源岩热演化、油藏形成和保存的影响，分析了海相地层油气资源潜力，揭示了两期油气充注，主要发生在三叠纪至侏罗纪晚期，为南黄海盆地资源调查奠定了基础。. 已在Marine and Petroleum Geology, Journal of Asian Earth Sciences, Energy&fuels等国际著名期刊发表相关SCI论文4篇，其中，1篇论文入选ESI高被引论文；出版《南黄海地质构造演化—CSDP-2井实录》专著1部，入选“十三五国家重点图书出版规划”；成果《东亚中生代构造转换的热史记录及对南黄海油气勘探的指示意义》获2020年度（第七届）山东地学科技创新奖。