利用地震资料预测断裂发育区泥岩盖层封油气区的方法

Method for predicting oil and gas sealing area of mudstone caprock in fracture development zone by seismic data

为了研究断裂发育区泥岩盖层在油气成藏与分布中的作用,在断裂对泥岩盖层破坏程度研究的基础上,通过断裂对泥岩盖层的破坏程度与其上下油气分布关系,确定出了泥岩盖层封油气所需的最大破坏程度.通过比较断裂对泥岩盖层破坏程度与其封油气所需最大破坏程度的相对大小,建立了一套利用地震资料预测断裂发育区泥岩盖层封油气区的方法,并将其应用渤海湾盆地冀中凹陷留楚地区断裂破坏东一、二段泥岩盖层封油气区的预测中,结果表明:留楚地区断裂破坏东一、二段泥岩盖层封油气区主要分布在留楚地区东部、西部中部和北部地区.东一、二段泥岩盖层非封油气区则主要分布在北部留楚背斜核部、西南广大地区和西北局部地区,与目前留楚地区其下东二、三段和其上馆陶组已发现油气仅分布在非封闭区相吻合,表明利用地震资料预测断裂发育区泥岩盖层封油气区是可行的.

In order to study the oil-gas accumulation and distribution effect of fault damage zone＇s mudstone caprock,based on the study of the damage degree of faults to mudstone caprock,by analysing the degree of fault＇s damage and the relationship with its upper and lower oil-gas distribution,the maximum damage degree of Mudstone Caprock Sealing Oil and gas is determined. By comparing the mudstone caprock ＇s damage degree from the faults to the maximum extent of damage required sealing oil-gas,set up a method for predicting Oil and gas sealing area of mudstone caprock in fracture development zone by seismic data,and applied it into the prediction of Ed1 and Ed2 mudstone caprock configuration sealing oil-gas destructed by fault transportation in Liuchu area of Bohai bay basin Jizhong depress, The result indicated that Ed1 and Ed2mudstone caprock space configuration sealing oil-gas destructed by fault transportation in Liuchu area are mainly distributed in east、west central and north regions in Liuchu area,fault-caprock space configuration section non sealing ability of oil-gas areas are mainly distributed in northern Liuchu anticline core、southwestern vast areas and northwestern local areas,and it coincided well with the current distribution of oil-gas found in Ed2、Ed3 and Ng section of Liuchu area,indicates this method is feasible to predict the fault-caprock space configuration sealing ability of oil-gas by seismic data.