Abstract: Based on the analysis of the vertical sealing mechanism of static fault and its affcting factors, simulation of the cutoff value of shale content required in hydrocarbon sealing by static fault zone with different grain sizes is made. The result shows that the coarser the grain size in fault zone is, the lower the shale content requirement for oil-gas sealing is, and on the contrary, the higher the shale content requirement is. Using this result, as evaluating standard, to vertical oil-gas sealing evaluation of several major faults in northern Wuerson sag, good suitability is gained. It is indicated that such a standard for ev aluation of vertical oil-gas sealing in fault is feasible to use.

Key words: fault, fault zone, sealing, physical simulation, shale content