西南非海岸盆地层间麻坑的形成机理及其指示意义  

Evolution and genesis of intra-formation pockmarks in southwest African coastal basin

作　　者：王剑 杜向东 张树林 尹川 李萍 

机构地区：[1]中海油研究总院,北京100028

出　　处：《地球物理学进展》2016年第1期469-475,共7页Progress in Geophysics

基　　金：国家科技重大专项30项目课题四"大陆边缘盆地地球物理勘探关键技术攻关与应用研究"(2011ZX05030-004)资助

摘　　要：麻坑是由于地下流体超压喷发而在海底形成的凹陷坑.按其分布层位可划分为层间麻坑和海底麻坑,而海底麻坑又可按其活跃状态划分为海底休眠型麻坑和海底活跃型麻坑.海底麻坑是全球海域含油气沉积盆地普遍发育的一种麻坑类型,而层间麻坑是一种较少见的麻坑类型.在研究西南非海岸盆地油气成藏条件时,发现该盆地发育层间麻坑现象.这种层间麻坑具有多期次发育的特点,在地震剖面上表现为强振幅、多期同相轴下拉叠加的特点,剖面形态为"V"或"U"型,从三维地震数据体沿层属性切片上能看到明显的异常带.本文通过对三维地震数据的解释,较为系统地研究了西南非海岸盆地层间麻坑的构型、演化模式及形成机理,并简要总结了层间麻坑对盆地油气勘探的指示意义.Pockmarks are escape phenomena of gas or liquid from the sediment. They can be classified into seabed pockmark and intra-formation pockmark which is rarely seen. Seabed pockmarks are common phenomenon in offshore petroleum basin. In Southwest African Coastal Basin, lots of intra-formation pockmarks are identified by using 3D seismic data. The intra-formation pockmarks present multiple pulling-down seismic events overlay vertically in seismic profiles and anomaly belts in seismic attributions. The evolution and genesis of intra-formation pockmarks in this basin are researched by using 3D seismic data. By researching the intraformation pockmark,we can get more useful information for the basin petroleum exploration.

关 键 词：西南非海岸盆地 海底麻坑 层间麻坑 同沉积 沿层切片 油气指示 

分 类 号：P631[天文地球—地质矿产勘探] P738[天文地球—地质学]