海侵背景下风暴控制的滨岸—陆棚砂体研究——以塔中志留系下沥青砂岩段为例

Study on Transgressive Storm-dominated Shoreline-neritic Shelf Sandbody: a case of the lower bitumen-bearing sandstone member of Silurian in Tazhong Area

塔中志留系下沥青砂岩段发育海侵背景下受风暴控制的滨岸—陆棚沉积体系,沉积砂体的类型有滨岸砂、浅海砂坝和陆棚砂。风暴作用改造并控制着陆棚砂、浅海砂坝等砂体,使其发育规模增大。海侵时期形成的上述三种砂体的储集性优于海退时期形成的潮道砂体。滨岸砂、浅海砂坝和陆棚砂体区域上尖灭与陆棚泥岩组合,可形成较好的岩性地层圈闭。

Transgressive storm-dominated shore-neritic sedimentary system was developed in the lower bitumen-bearing sandstone member during Silurian period of Tazhong area in Tarim basin. The types of sandbody are shore sandbody, neritic sand bar and shelf sand in the lower bitumen-bearing sandstone member. After the storm, the distribution of shelf sand became larger than before. The physical property of sandstone during progression is better than that of sandstone of tidal fiat during marine regression. There are many different characters on the sand bodies, and the shore-neritic sand bodies are the very important reservoir for the stratigraphic traps.