预测郭局子洼陷灰岩储层的两种有效地震属性

郭局子洼陷南坡沙四段灰岩发育，是该区主要的产油层，灰岩储层类型主要为孔隙和裂缝型。该套灰岩在地震剖面上表现为强反射，仅仅利用常规地震属性难以有效地把灰岩厚度横向变化和灰岩储层发育区反映出来。应用分频振幅属性预测灰岩厚度和展布，应用瞬时频率属性预测储层的孔缝发育带，预测结果与已完钻井吻合很好。评价认为，在目前勘探程度较低的洼陷南部缓坡带，灰岩储层厚度较大、孔缝发育、储集性能较好，具有较大的勘探潜力。

Two effective attributes for limestone reservoir prediction in Guojuzi sag

In Guojuzi sag, limestone, which is the main pay bed in this region, is developed in the south slope. Though the limestone is manifested by strong reflection, it is hard to determine the lateral variations of limestone thickness and limestone reservoirs simply by conventional seismic attributes. This paper proposed to determine the thickness and distribution of limestone by frequency division amplitude and the fracture zone by instantaneous frequency. The predicted results are in good agreement with drillings. It is concluded that the south slope that has been poorly explored is a favorable prospect. The limestone is thick and fractured, and its reservoir property is favorable.