The secondary dolomite and paleokarst of the Lower Permian Series in Sichuan Basin is one of the important atectonic reserviors in the basin.

四川盆地中次生白云岩及古岩溶是主要的非构造圈闭一。

Rich hydrocarbon accumulation area is usually associated with structure-lithology trap, fault trap and lentoid sand trap.

有利圈闭为岩性、构造岩性、断块及断类型。