中国大陆南缘不活动大陆边缘和拉裂盆地

PASSIVE MARGIN AND PULL APART BASINS IN SOUTHERN CHINA

中国大陆南缘经历了太平洋板块和特提斯板块与欧亚板块会聚作用的复杂过程,并在不晚于早第三纪早期,已经由活动的大陆边缘转换为不活动的,具有典型的不活动边缘的重力效应特征。根据构造演化分析,大陆南缘的陆缘盆地属不活动边缘拉裂盆地,南海中央海金则属于边缘海盆地。本文阐述了亚洲大陆南缘的主要转换断裂系统,讨论了这些断裂系统所反映的太平洋—特提斯板块和欧亚板块之间板块边界的应力机制和活动方式,认为在特提斯—印度洋域,这些转换断裂系统从西向东延伸,分别属于右旋和左旋滑移。它们对中国大陆南缘边缘构造带和含油气盆地的形成和地质演化起着重要的作用。

The southern margin of Chinese continent underwent a complicated convergence process of Eurasian plate and Pacific plate and Tethys plate and transformed from active into passive continental margin no later than early Eogene.The southern China continental margin is characterized by typical passive continental gravity effect.According to an analys is of tectonic evolution,the southern China continental margin basins belong to passive margin pull-apart basins,and the central area of southern China sea basin is margin sea basin.This paper illustrates the main transform fault series around the Southern Asia continental margin.The stress regime and the activity form of boundaries between the Pacific-Tetbys plate and the Eurasian plate as reflected by the presence of such a fault-series are discussed.In the Tethys-Indian Ocean region these fault series belong to dextral slip and sinistrals lip extending from west to east.These transform fault series play an important role in the formation and the geological evolution of the Southern China continental margin tectonic-structural zones and oil/gas bearing basin in the Southern China continental margin.