Abstract:

The western Sichuan depression has experienced very complicated evolution.As a result,it is characterized by vertically stacking of various basin types,multiple styles of trap strucuture,multiple source and resevoir rocks, and multiple superimpositions and reconstructions.Although abundant petroleum resources have been generated, the special distribution of oil and gas is under-concentrated.Systematic study of dynamics of hydrocarbon reservoiring indicates that there might have been late reservoiring condition in this area, and major migration and accumulation of oil & gas might have occurred before the reservoirs to be tightened.Forming phase of trap is crucial to trap validity,and the features of composite petroleum system control the distribution pattern of gas reservoirs to be three-dimensionally in groups.According to the characteristics of hydrocarbon resources in western Sichuan depression and aiming at the large prospecting targets,main objects of near and medium term exploration plans should be focused on deep gas reservoirs,expanding exploration of moderate deep gas reservoirs and extending the periphery shallow gas reservoirs.

Key words: western Sichuan depression, oil &, gas resources, dynamic system of hydrocarbon accumulation, prospecting target