酒西坳陷下白垩统近岸水下扇沉积特征及控制因素分析  

Sedimentary Characteristics and Controlling Factors of Lower Cretaceous Nearshore Subaqueous Fans in Jiuxi Depression

作　　者：曹正林[1,2] 苟迎春[2] 郑红军[2] 王斌婷[2] 李延丽[2] 

机构地区：[1]中国石油勘探开发研究院博士后流动站,北京100083 [2]中国石油勘探开发研究院西北分院,甘肃兰州730020

出　　处：《天然气地球科学》2009年第6期896-901,共6页Natural Gas Geoscience

基　　金：中国石油天然气股份有限公司勘探生产分公司勘探前期评价项目(编号:KTQQ-2005-017)资助.

摘　　要：酒西坳陷石大凹陷为一东断西超的中新生代箕状断陷湖盆。早白垩世早期,在右旋扭动背景下受局部拉张作用的影响,凹陷内形成了一系列NE、NNE向张扭性断裂,这些张扭性断裂控制了石大凹陷下白垩统的沉积,在湖盆陡坡带主要发育了独具特色的近岸水下扇砂岩沉积体。石大凹陷陡坡带控凹边界断层在早白垩世早期的强烈活动是导致近岸水下扇形成的决定性因素。近岸水下扇砂体常常下切到深湖—半深湖暗色泥岩,油源条件得天独厚,决定了近岸水下扇砂体具有优越的成藏条件。开展近岸水下扇沉积特征及控制因素的研究对指导断陷湖盆岩性油气藏勘探具有重要意义。The Shida sag is a half-graben fault depression lake basin which has fault in the east and onlap in the west.In Early Cretaceous, lots of transtensional faults of NE and NNE trend were formed under right lateral forces, they controlled the Lower Cretaceous sedimentation and led to nearshore subaqueous fans in the steep slope.The strong movement of the fault boundary in the Early Cretaceous epoch resulted in the formation of inshore subsea aprons.The sand bodies of the nearshore subaqueous fans cut down into the dark colored mudstones of deep lake and half-deep lake.It makes the sand bodies of the nearshore subaqueous fans have excellent conditions of petroleum accumulation.

关 键 词：酒西坳陷 石大凹陷 近岸水下扇 沉积特征 岩性油气藏 

分 类 号：TE121.3[石油与天然气工程—油气勘探]