琼东南盆地2号断裂东带发育特征及形成机理

本文通过2号断裂陵水带、松南带基本结构及特征分析了它自新生代以来特别是古近纪的活动史和构造-沉积发育史。并发现,2号断裂松南带发育比陵水带更加复杂的结构样式,在此基础上,结合该断裂带的深部切片和地震资料,运用断层传播连接热点理论剖析了这种结构的成因,认为2号断裂松南带以L1023测线为界在成因上存在较大差异,这种差异是由早期断陷和所控充填方式都不同的两条断裂交叉连接而成,而且指出了这种成因断裂在油气勘探中应该注意的问题和意义。

FORMING MECHANISM AND DEVELOPING CHARACTERISTICS OF EASTERN SEGMENT OF NO. 2 FAULT ZONE IN QIONGDONGNAN BASIN

Compared with the Yacheng dome, the eastern Segment of the No.2 fault zone in Qiongdongnan basin is considered to be another significant area for oil and gas exploration. In this article, by means of primary structures and other characteristics of the No.2 fault zone in the Lingshui and Songnan depressions, the history of fault activity and process of structural-sedimentary evolution since the Cenozoic especially early Cenozoic are analyzed. The Songnan segment of the No.2 fault zone presents more complicated configurations and styles than that in Lingshui segment. on the basis of this phenomenon, combined with deep level intersections and earthquake data, hot theories of fault propagation and fault linkage are applied to analyze its genesis. The results indicate that, the fault zone in the Songnan depression is greatly different between two sides of L1023 for the mechanism of formation, it is derived from two primitive faults by manners of intersecting and linkage, and which have led to different rifting and filling mode today. Furthermore, key problems that should be paid more attention to this kind of fault forming condition, and their significances are pointed out for oil and gas exploration.