浅析川西坳陷燕山中、晚期构造圈闭的有效性

SIMPLE ANALYSIS ON THE EFFECTIVENESS OF THE MIDDLE AND LATE　YANSHANIAN TECTONIC TRAPS IN THE WEST SICHUAN DEPRESSION

岳东明 王信

YUE Dongming WANG Xin

中国新星石油公司 西南石油局 研究院, 四川 成都 610081

Research Institute of Southwest Petroleum Bureau, CNSPC, Chengdu, Sichuan 610081, China

川西坳陷致密砂岩领域,蕴藏有丰富的天然气资源。勘探表明:K1-T3x2有16套含气组合的40个气层,埋深200～4500m.气层错落叠置,连片成带,其空间展布显示出了燕山中、晚期构造的关键作用。究其原因是燕山中、晚期为川西坳陷主力烃源岩的生气高峰期,大多数砂岩储层尚未致密仍处于有效聚集孔隙阶段,致使当时的正向构造带成为主要的油气聚集带。因此,川西坳陷勘探进程中,应加强燕山中、晚期构造圈闭的研究。

The tight sandstone tracts of the West Sichuan Depression are rich in natural gas resources.Exploration reveals that there are 16 sets of gas-bearing assemblages composed of 40 gas layers in K1-T3x2 formations at the depth from 200m to 4500m.The gas layers are scattered and overlapped,and connect into zones.Their space distribution shows the key effect of the Middle and Late Yanshanian tectonics.As the Middle and Late Yanshanian periods were peak time of gas generation from major hydrocarbon source rock in the West Sichuan Depression and most sandstone reservoirs had not been compacted yet and still remained in the porous stage with effective accumulation,main hydrocarbon accumulation belts formed along the normal tectonic belts at that time.Therefore,the research of the Middle and Late Yanshanian tectonic traps should be reinforced in the course of exploration in the West Sichuan Depression.

国家"九五"科技攻关课题

https://doi.org/10.11781/sysydz199902128