Based on the outcrop features and conventional petrophysical properties,the reservoir characteristics of T1j2 of Zhaigouwan structure in eastern Sichuan are studied.The result shows that the reservoir rocks are mainly composed of crystal grain dolomite and particle dolomite.The reservoir spaces are mainly intercrystal pores and dissolved pores. The reservoir properties are poor.The reservoir types are fracture-pore and pore-fracture.Reservoirs mainly developed in T1j22 along longititudinal direction,less in T1j21 and partly in T1j23.Reservoirs of T1j22 developed well in Zhaigou 2 well and Zhaigou 4 well,while reservoirs of T1 j21 developed well in Zhaigou 4 well.Sedimentation not only controls the development and distribution of reservoir,but also affects the basic pattern of reservoir and the type and intensity of diagenesis.It is the dominated factor controlling the reservoir development.Diagenesis determines the reservoir space and reservoir performance,and directly influences the forming and evolution of pore space.Tectonism provides conditions for the above activities.

According to available data from the menber 1 of Xishanyao Formation of Jura-ssic in Baijiahai Uplift,Junggar Basin,three types of sedimentary facies are identified.Each lithology feature,sedimentary structure and vertical sequence are analyzed in details.Furthermore,the planar distribution of the facies are described.Finally,the favorable facies is pointed,which offers a reliable basis for further exploration in the area.

There are many source rocks developed at South Poyang Depression, mainly including the Upper Permian Longtan Formation of dead color mudstone and coal, the Lower Permian Maokou Formation of marl and the Lower Permian Xixia Formation of limestone. Integrated barkinite and vitrinite in coal, a hydrocarbon-generating simulation was carried out and a hydrocarbon-generating potential was explored for the main source rocks in this study area. These results illustrate that either barkinite or vitrinite are of very strong potential, in which an oil generation of barkinite is much stronger than that of vitrinite. As for Maokou and Longtan formations, a hydrocarbon-generating intensity in mud source rock shows that the maximum occurs at southwestern depression and a decrease trend appears from north to east. Additionally, the thickness of source rock at southwestern depression is the largest, reflecting the southwestern depression is a favorable exploration area.