中国南部海域主要断裂类型、分布及地质特征

中国南部海区及邻域1∶1 000 000地质地球物理系列图已编制完成并即将出版,区域构造图是其中的主要图件之一,据此成果,讨论了中国南部海域主要断裂类型、分布及地质特征。主要断裂类型有俯冲带、碰撞缝合带、转换断层、扩张脊型断裂、大型走滑断裂及深大断裂等。根据断裂规模及控制的地质构造单元性质划分出了一级断裂和二级断裂。一级断裂主要是指俯冲带、碰撞缝合带或者控制构造域、地块之间界线的深大断裂;二级断裂主要是控制隆褶带、海盆区以及大型沉积盆地的深大断裂。这些断裂大多具有形成时期早、规模大、断层延伸远、断距大甚至多次活动的特征。

TYPES, DISTRIBUTION AND GEOLOGICAL FEATURE OF THE MAIN FAULTS IN THE SOUTHERN CHINA SEAS

The Geological-Geophysical Map Series of the Southern China Seas and Adjacent Region (1∶1 000 000) will be published soon.The Regional Tectonic Map is one of the major maps. This paper mainly discusses the types, distribution and geological features of the main faults in the mapping area. The subduction zone, collision zone, transform fault, expansive ridge fault, large slide fault, deep-and-large fault etc. are the main types of faults. The first grade faults and the second grade faults were distinguished according to the scale of the faults and the features of the controlling geo-tectonic units. The first grade faults generally the subduction zone, collision zone and the deep-and-large faults controlling tectonic domains and blocks, and the second grade faults mainly the deep-and-large faults controlling folded belts,sea basin zones, and sedimentary basins of large scale. Most of these faults are characterized by their oldness, large scale, long spread, large fault distance and reactivation.