摘要
Gaoyou Sag is the area with the highest degree exploration and the greatest oil potential in Subei Basin.In order to reveal the key role of fault acting as vertical migration pathway or lateral sealing in hydrocarbon accumulation and distribution,the characteristics of fault sealing were comprehensively analyzed with the methods of lithology juxtaposition and shale smear in this paper.Result shows that lithology juxtaposition is the critical factor of fault sealing in the case of thick regional cap rock and large fault throw available.But when lithology juxtaposition does not match excellently,shale smear directly decides the fault lateral sealing.The quantitative estimation shows that the lower limit of shale gouge ratio(SGR) is more than 0.65 and fault has sealing capability which is in proportion to SGR.