松辽白垩纪湖盆湖水环流与隐蔽油藏勘探

THE STUDY OF ANNULAR DRAINAGE OF THE ANCIENT LAKE AND THE PROSPECTING FOR SUBTLE OIL POOLS IN CRETACEOUS SONGLIAO LACUSTRINE BASIN

安作相

An Zuoxiang

中国石油学会

Chinese Petroleum Society

从众多的地震大剖面分析,松辽盆地的白垩系,尖灭和超覆现象仅在盆地各凹陷的边缘存在,主要为浅湖相的沙滩、沙坝和沙堤等所组成的砂岩透镜体。而这些砂岩透镜体的空间分布及其控制因素与湖水的环流密切有关。

The extent of Songliao lacustrine basin in Cretaceous time reached its maximum during the deposition of Qingshankou Formation,covering approx-imately 150,000km2.the uplifting of lake bottom at Daqing,Yangda-chengzi,Fuyu,and Suileng separated the basin into two parts:the east depression and the west depression.The rivers on the northern margin and the western margin of the lacustrine basin all entered the ancient lake,forming an annular drainage.the drainage pattern resulted in a coil-like distribution of the sand bars in the shallow and deeper parts of the lake,which after diagenetic compaction,formed anticlinal features of low elevation.As source rocks generally occurred in the central parts of the drainage system,these bars became favourable sites for the formation of subtle oil pools.

https://doi.org/10.11781/sysydz198502107