Abstract: According to the different exploration levels of J-K (shallow and middle strata)and Xujiahe formation(deep strata)in the middle part of West Sichuan depression, the pool size sequence method is selected to calculate the amount of natural gas resources of J-K, reservoir volume method to calculate the amount of natural gas resources of Xujiahe formation. The results show that natural gas geological conditions in this area are preferable and rich in natural gas resources, with the amount of natural gas resources in place of about 1.161×10¹²m³. At present, the resources proven degree is only 14.68%, revealing that it is in the early fast development stage for gas exploration as a whole, with huge gas resources potentials. This will be as a guide for further gas exploration deployment and the midand long-term development goal establishment.

Key words: West Sichuan depression, natural gas resources, pool size sequence method, reservoir volume method