岐口凹陷大型远岸水下扇成因  

ORIGIN OF THE LARGE FARSHORE SUBAQUEOUS FAN IN QIKOU SAG

作　　者：陈少平 

机构地区：[1]中海油研究总院,北京100028

出　　处：《大庆石油地质与开发》2015年第4期21-27,共7页Petroleum Geology & Oilfield Development in Daqing

基　　金：国家科技重大专项"近海大中型油气田形成条件及勘探技术"(2008ZX05023-001)资助

摘　　要：大型远岸水下扇砂体既是良好储集层,又是重要的油气输导体,其成因分析对寻找与之相关的岩性油藏具有重要意义。应用沉积学、层序地层学等方法,在统一地层格架的基础上,对岐口凹陷沙一、二段的大型远岸水下扇成因及油气藏分布进行了探讨。研究认为:北部燕山褶皱带充足的物源、广泛发育的深水沉积环境及盆内近东西向大规模断裂坡折带是大型远岸水下扇的主要成因;远岸水下扇主要岩性为深湖相泥岩夹细砂岩、粉砂岩,砂岩具有较高的结构、成分成熟度,是良好的储层类型,同时对油气的运移方向和油气运聚单元的划分有着重要的影响,陆上远岸水下扇砂体更为发育,汇聚的油气也更多。The sand bodies of the large farshore subaqueous fan are not only the much better reservoirs but also the important oil and gas transmitting conductors, so it is important significance for the lithologic reservoir discovery to conduct the relative genetic analysis. With the help of the following methods such as the sedimentology, sequence stratigraphy and so on, on the basis of the unified sequence stratigraphic framework, the gneisses of the large farshore subaqueous fan in Member Shal-2 and petroleum reservoir distribution in Qikou Sag are explored. The research shows that the adequate source form North Yanshan Fold Belt, widely well-developed deep-water sedimentary environment and near EW developed large-scale slope break belts inside the basin are the main genetic factors of the large farshore subaqueous fan. The principal lithologies of the above fan are deep lacustrine mudstone intercalated with fine sandstone and siltstone with high structural and compositional maturities, so the sandstones are good reservoirs. At the same time, they possess important influences for the hydrocarbon migration direction and accumulation unit partition. And furthermore the sandbodies of the terrestrial farshore subaqueous fan are much more welldeveloped and enriched with more oil and gas.

关 键 词：歧口凹陷 沙一 二段 砂体 远岸水下扇 油气运聚 

分 类 号：TE121.3[石油与天然气工程—油气勘探]