北部湾盆地海中凹陷断层活动性及其对沉积的控制

Activities of the Major Faults and Their Control on Deposition in Haizhong Depression, Beibuwan Basin

郑军 葛翔

ZHENG Jun GE Xiang

中国石油化工股份有限公司上海海洋油气分公司研究院, 上海 200120; 中国地质大学构造与油气资源教育部重点实验室, 湖北武汉 430074

Institute of SINOPEC Shanghai Offshore Oil & Gas Company, Shanghai 200120, China; Key Laboratory of Tectonics and Petroleum Resources, China University of Geosciences, Ministry of Education, Wuhan Hubei 430074, China

运用断层活动速率法,定量分析了海中凹陷涠西南断层与3号断层的活动特征。在凹陷演化过程中,涠西南断层的活动速率自长流组至涠洲组呈现为由强到弱的变化趋势,3号断层则自涠洲组开始强烈活动,两条断层共同控制了海中凹陷的发育与演化。涠西南断层与3号断层不同时期的差异性活动还控制了凹陷沉积中心与沉降中心的形成与迁移。断陷时期的沉降作用受控于构造作用,沉降作用又制约着沉积作用的发生和发展。

The activity rate of Weixinan fault and No.3 fault of Haizhong depression was quantitatively calculated by fault activity rate method. During the evolution of Haizhong depression, the activity rate of Weixinan fault turned strong to week from Changliu period to Weizhou period and the activity of No.3 fault became intensely from Weizhou period. The two faults controlled the development and evolution of Haizhong depression. Moreover, the different active features in different time of the two faults influenced the formation and migration of the deposition center and sedimentation center in this depression. The sedimentation in this depression was controlled by tectonism, and the subsidence also restricted the occurrence and development of the deposition.

https://doi.org/10.3969/j.issn.1008-2336.2014.04.001