珠江口盆地白云凹陷断裂构造特征及其活动期次  

Fault structure and evolution of Baiyun Sag in Zhujiang River Mouth Basin

作　　者：孙龙涛[1] 周蒂[1] 陈长民 詹文欢[1] 孙珍[1] 

机构地区：[1]中国科学院边缘海地质重点实验室、中国科学院南海海洋研究所,广东广州510301 [2]中海石油中国有限公司深圳分公司技术部,广东广州510240

出　　处：《热带海洋学报》2008年第2期25-31,共7页Journal of Tropical Oceanography

基　　金：国家自然科学基金项目(40576027);中国科学院知识创新工程重要方向项目(KZCX2-SW-117-05)

摘　　要：对白云凹陷地震资料的解释分析表明,该凹陷断裂构造以正断层和走滑断裂为主,未见逆断层。在平面上,断裂主要为NWW至近EW走向,不同等级与不同走向断层表现为平行断层系、帚状断层系和雁列断层系等三种断层组合形式。剖面中,单条断层样式相对简单,主要呈现平面式、铲式和座椅式等构造样式;多条断层主要表现为花状组合、马尾状组合、Y字型组合和阶梯状组合等构造特征。通过对断裂活动强度统计发现,不同区域断裂的发育时间和发育强度亦有差异,其中50—30MaBP是断裂的强烈发育期,控制凹陷的同张裂期沉积充填;13.8—10MaBP受东沙运动的影响断裂再次活化,属于中等强度发育期。Baiyun Sag （BYS） lies in the deep water area of the Zhujiang River Mouth Basin （PRMB）. It is the largest, deepest and most potential sag in the north margin of the South China Sea. The faults in the BYS are mainly in normal type and may be divided into three groups by orientation, i.e. NWW, E-W and NE, with NWW predominant. On plane view these faults form parallel, fastigiated, and en echelon combinations. In vertical sections these faults form flower, horsetail, or ladder shaped combinations, while a single fault may be of planar, listric, or chair shape. The fault movement velocity varies in difference districts. Statistics indicates that the strongest fault activity occurred during the period of 50-30MaBP and controlled the sag formation and the syn-rifting sedimentation. The faulting rejuvenated in the Dongsha movement （13.8-10MaBP） with secondarily strong activity.

关 键 词：白云凹陷 珠江口盆地 断裂 构造活动 

分 类 号：P542.31[天文地球—构造地质学]