作　　者： ; ; ; ; ;

机构地区： 中国科学院广州地球化学研究所边缘海地质重点实验室

出　　处： 《高校地质学报》 2005年第1期105-110,共6页

摘　　要： 通过对南海南北边缘地震剖面的对比,结合周边构造分析,提出南海大陆边缘的裂离经历了两期伸展作用,即早期的简单剪切和晚期的纯剪切伸展作用。简单剪切发生在晚白垩世—早始新世,其动力与太平洋板块俯冲带的后撤、太平洋板块与欧亚板块之间汇聚速率的降低、以及先存北倾缝合带等密切相关。纯剪切发生在中始新世—渐新世/早中新世。 Based on examining the seismic profiles distributed at the north and south margins of South China Sea, combined with the tectonic analysis of its adjacent area, the authors pointed out that this region experienced two periods' extensions, i.e. the earlier simple shear and the later pure shear. The simple shear extension mainly occurred in Late Cretaceous-Early Paleogene, related to slab roll back of Pacific plate, decreasing Paleogene Pacific-Eurasia convergence rate and possible preexisting suture zone. Pure shear happened in response to the extensional slab pull forces from southward subduction of the Paleo-South China Sea beneath Borneo during the Oligocene and Miocene.

关 键 词： 南海 北部陆缘 伸展模型

领　　域： [天文地球] [天文地球]