The global unconventional oil and gas resources have huge potential

and now have become an important target for hydrocarbon exploration and exploitation and also a key field for increasing oil and gas reserves and production in the future. The continental tight sandstone gas in the Triassic Xujiahe Formation and Jurassic reservoirs

as well as the Jurassic tight oil and shale oil are new fields for oil and gas exploration and exploitation in Sichuan Basin

which play a crucial role in petroleum resources composition

of the basin. Sichuan Basin experienced the tectonic evolution of Longmenshan foreland basin and intracontinental depression basin in the Late Indosinian-Yanshanian period

and the evolution of three second-order sequences in the Late Indosinian period has a controlling effect on the interstratified source-reservoir superposition in Xujiahe Formation

thus determining the formation of in-source and near-source gas reservoirs. The lacustrine transgression and delta-river depositional systems developed in Yanshanian period evolved into the Lower Jurassic source rocks and the high-quality sand bodies of Shaximiao Formation

respectively

and the source rocks of Xujiahe Formation were connected with large-scale faults

which laid the foundation for the formation of tight gas reservoirs in Shaximiao Formation. Indosinian foreland basin and Yanshanian depression basin are the key areas for tight oil and gas exploration in Sichuan Basin in the future. The delta sand bodies developed at the periphery of lake basin in Member 3 to 5 of Xujiahe Formation in the western-central Sichuan Basin and the shallow-water delta-channel sand bodies in the east of central Sichuan Basin are favorable exploration fields for tight gas

of which the estimated resources exceed 3.0×10

12

m

3

and 0.5×10

12

m

3

respectively. In addition

the Lower Jurassic tight oil and shale oil also have a certain resource potential.