南海扩张的动力学因素及其数值模拟讨论  

DYNAMIC FACTORS FOR THE OPENING OF SOUTH CHINA SEA AND A NUMERICAL MODELING DISCUSSION

作　　者：夏斌[1] 崔学军[1] 张宴华 刘宝明[1] 王冉[1] 闫义[1] 

机构地区：[1]中国科学院边缘海地质重点实验室,中国科学院广州地球化学研究所,广东广州510640 [2]CSIRO Exploration & Mining, P.O.Box 1130, Bentley, WA 6102, Australia

出　　处：《大地构造与成矿学》2005年第3期328-333,共6页Geotectonica et Metallogenia

基　　金：中国科学院知识创新工程重要方向性项目(KZCX2-SW-117)资助.

摘　　要：由于南海处于欧亚板块、太平洋板块和印度-澳大利亚板块的交汇区,演化历史十分复杂,历来存在多种成因观点的争论。本文采用数值模拟方法,在XiaBinetal.(2005)、夏斌等(2004)、崔学军等(2005)、谢建华等(2005)相关工作基础上,对南海扩张机制进行了进一步探讨,并针对南海地区“近南北向水平拉张”南海扩张的贡献大小,以及“近南北向水平拉张”与“地幔上涌”在南海扩张中作用的相互关系进行了数值模拟实验。结果表明由印度-欧亚板块碰撞和太平洋板块向欧亚板块俯冲的共同作用,所导致的“南北向构造拉张”和“地幔上涌”的共同作用能有效引起岩石圈和地壳两者很大程度的减薄。因此认为这种“南北向构造拉张”和“地幔上涌”的共同作用方式最有利于南海的扩张。The dynamic mechanism for the expansion of South China Sea together with its tectonic evolution and structural characteristics is discussed in this paper. As South China Sea is located on the convergent hinge among the Eurasian plate, the Pacific plate and the Indo - Australian plate, the tectonic evolution and the dynamic mechanism for the formation of South China Sea are very complicated. Based on our study on the tectonic evolution and the dynamic mechanism for the formation of South China Sea, a numerical approach was used to explore the behaviors of the “tectonic extrusion” and the “asthenosphere upwelling”. It is suggested in this paper that it is the combination of mechanical extension and asthenosphere upwelling that proves to be the most efficient way to thin the entire lithosphere, and that represents the most likely driving force for the opening and spreading of the South China Sea.

关 键 词：南海扩张 动力学机制 数值模拟 地幔上涌 

分 类 号：P541[天文地球—构造地质学]