There are three types of shallow reservoirs controlled by different key factors for hydrocarbon accumulation in the North Jiangsu Basin,respectively controlled by low maturity and high efficiency oil source rock in the lower-middle part of the Fu2 Member,fault of vertical migration pathway,and large scale sandstone for lateral migration.

During middle-late stage of shallow layer reservoir development, amplifying production pressure difference and improving drainage amount are important approaches to improve oilfield development effect.

The distribution of shallow gas reservoirs in western Sichuan Depression: Examples from Luodai and Xinchang gas fields;

The shallow gas reservoir discovered in Shanle,Hongtai and Santanghu area are characterized by complex lithologies,poor physical property,unobvious response of logging,obvious productivity difference and sharp lateral variations of stratum etc.

Gudong shallow gas reservoirs are typical shallow porous sandstone reservoirs which are at the late period of development at present.

The shallow gas pools of Shengli Oilfield are lithological trap,its buried depth is less than 1500m and mainly located in Neogene Guantao and Minghua Formation.

In Shengli petroleum province,shallow gas pools,dominated by lithological trap,are less than 1500m in depth,and mainly located in Neogene Guantao and Minghuazhen Formation.