P波各向异性裂缝预测技术在ZY区碳酸盐岩储层中的应用

利用地震数据较为准确地预测碳酸盐岩中的裂缝发育区,是碳酸盐岩裂缝型储层预测的关键手段。文中介绍了基于HTI(具有水平对称轴的横向各向同性)介质P波各向异性裂缝预测方法的原理及思路流程,从ZY区成像测井及岩心资料的裂缝发育情况出发,以叠前地震数据为基础,进行研究区碳酸盐岩裂缝分布特征的预测。通过与衰减有关的P波各向异性得到研究区的裂缝发育特征,认为裂缝发育情况与断层展布特征关系密切,区内裂缝方向以北东向为主,北北东为辅。成像测井及岩心资料上的裂缝信息验证了预测结果的可靠性和准确性;在预测裂缝分布特征基础上设计的井位,试油也获得工业油流。以上理论和应用实践表明,P波方位各向异性裂缝预测方法能够准确预测碳酸盐岩储层裂缝的分布特征,有效提升油气预测的成功率。

Using P-wave azimuthal anisotropy to predict fractures in carbonate reservoirs of the ZY block

One of the key technologies used to predict fractured carbonate reservoirs is to locate fractures with seismic data.The paper introduces an approach of fracture prediction based on P-wave azimuthal anisotropy of HTI medium and its application in the ZY block.Pre-stack seismic data were used to predict fracture distribution in carbonate reservoirs.P-wave azimuthal anisotropy in relation with attenuation reveals that the fracture growth in the study area is closely linked with the distribution of faults and the fracture azimuths are dominated by NE direction,followed by NNE direction.The prediction is confirmed by image logging and core data.Industrial oil flow was successfully tested in wells emplaced according to the prediction results.The practice shows that the approach can be used to accurately predict the distribution of fractures and therefore it is considered an effective way to improve the prediction of fractured reservoirs.