南海西部万安断裂活动特征及其对万安盆地的控制作用  

ACTIVITY FEATURES OF WAN′AN FAULT AND ITS CONSTRAINTS ON WAN′AN BASIN,WESTERN SOUTH CHINA SEA

作　　者：陈强 金庆焕 CHEN Qiang JIN Qinghuan(Guangzhou Marine Geological Survey, CGS, Guangzhou 510075, China)

机构地区：[1]中国地质调查局广州海洋地质调查局,广州510075

出　　处：《海洋地质前沿》2017年第10期1-8,共8页Marine Geology Frontiers

基　　金：中国地质调查局"全国海陆成矿图件编制更新"项目(KD 2017-226)

摘　　要：万安盆地位于南海西南部印支块体东南端即万安断裂以西地区。前人关于万安断裂活动特征及其对万安盆地形成演化的控制作用存在较多争议。通过对万安盆地区域地质背景、地质特征以及万安断裂走滑活动规律的综合分析认为,万安断裂是一条早期形成(中生代晚期)、多期活动的走滑断裂。万安断裂活动切割了盆地新生代地层,形成较多负花状构造,但该断裂仅引起盆地局部区域新生代地层产状变化,远离该走滑断裂的地层未受影响。万安盆地走滑伸展特征不甚明显,而具有明显的裂谷盆地特点,初步分析认为,万安盆地应为具有走滑性质的大陆边缘裂陷盆地。The Wan＇an Basin lies in the southwestern South China Sea, southeastern Indosinian block, to the west of the Wan＇an Fault. It has been a long term controversy on the activity characteristics of the Wan＇an Fault and its effect on the formation and evolution of the Wan＇an Basin. In this paper, re- gional geological settings and geological characteristics of the Wan＇an Basin and activity characteristics of the Wan＇an strike-slip fault are analyzed. The Wan＇an Fault was formed early in Late Mesozoic, and experienced a multi-stage activities later on. The Fault cut through the Basin, during which nega- tive flower structures formed. But the Wan＇an Fault only caused partial strata change, the strata away from the strike-slip fault were not affected. Thus the basin has obvious characteristics of a rift basin on continental margin.

关 键 词：万安断裂 活动特征 万安盆地 形成机制 南海西部 

分 类 号：P542.3[天文地球—构造地质学]