Abstract:

 Using Allan graphic method, shale smear factor method and fault gouge ratio method, this paper studied the lateral sealing characteristics of 8 faults in Fuyu reservoir in Chaochang area, Daqing oilfield. By use of the normal pressure of fault section and the intensity limit of plastic deformation of mudstone, the vertical sealing characteristics of these faults are studied. The lateral and vertical sealing degrees of these faults are identified in Nenjiang stage, later Mingshui stage and nowadays. Except fault No.6, other faults were opening in later Nenjiang stage, so it is easy to delivery oil and gas from Qingshankou source rock, and the nearby region of fault No.6 is lack of oil sources. Up to present, except fault No.5, other faults are sealed, these sealed faults play a role of barrier to hydrocarbon migration from the already existing reservoir. Because fault No.5 is lack of effective blocking for hydrocarbon migration in three periods, so it basically serves as a channel.

Key words: Chaochang area, fault, closure property, evolution