南海深部构造热演化及其对南海形成演化的控制作用

项目名称： 南海深部构造热演化及其对南海形成演化的控制作用

项目编号： No.91428205

项目类型： 重大研究计划

立项/批准年度： 2015

项目学科： 天文学、地球科学

项目作者： 徐行

作者单位： 广州海洋地质调查局

项目金额： 300万元

中文摘要： 岩石圈的热结构包含着南海形成演化过程的重要信息，是揭示南海构造演化和动力学过程的基础。本研究拟开展对南海海域的热流调查，并结合申请单位目前拥有覆盖南海的大量热流数据，获得南海全面和精细的热流分布。在此基础上结合多学科的最新资料和研究成果，建立岩石圈三维热结构和流变结构，并以此为约束利用数值模拟方法研究南海扩张过程中岩石圈热结构的演化，探讨岩石圈热结构对南海演化的控制作用。拟回答南海演化中的一些关键问题：南海裂谷过程中岩石圈破裂的动力学机制；中央次海盆是否存在洋脊跃迁、洋脊跃迁对南海扩张和火山影响作用和西南次海盆扩张模式等。本项目以地热学理论与方法为主线，综合多学科资料及研究成果，对南海岩石圈深部热结构研究采用由点到面,由“浅”到“深”，由“今”到“古”研究方法，海底热流调查、多种资料综合分析和数值模拟计算相结合，项目研究具有创新性和开拓性，可为《南海深部重大研究计划》集成提供补充。

中文关键词： 地热流；地球动力学；构造热演化；南海；流变

英文摘要： The thermal structure of the lithosphere could be used to reveal the tectonic evolution and dynamic process of South China Sea since it contains important evolution information in this region. We intend to carry out investigation of heat flow and joint use plenty of heat flow data accumulated over decades to obtain the comprehensive and fine heat flux distribution in South China Sea. And then construct 3D thermal and rheological structures of lithosphere with combination use of the latest data set and research achievements from multiple disciplines. Furthermore, with constraints of constructed structure model, we apply numerical simulation method to study the evolution process of thermal structure of lithosphere and its control effect on the evolution of South China Sea. We focus on some critical scientific issues associated with the evolution of South China Sea and try to give answers: ① the kinetic mechanism of lithosphere’s rupture during the spreading process of the South China Sea. ② whether there exists a ridge transition in the central subbasin, and its effect on the spreading of South China Sea, volcanic activity and the expansion type of southwest subbasin. Based on the theory and method of geothermic and combination of the multidisciplinary information and achievements, we present our study on the thermal structure of lithosphere in South China Sea by performing a strategy from point to surface, from shallow to deep, from ancient to present. This study will demonstrate its significance of innovation on comprehensive analysis from multiple data and combination use of investigation of heat flow and numerical simulation. It also will provide essential supplementary to the project of “the major research plan in the deep South China Sea”.

英文关键词： heat flow;geodynamics;tectonic thermal evolution;South China Sea;rheological