泾河油田长8致密油藏地震Likelihood裂缝预测

Seismic Likelihood fracture prediction technology for Chang-8 tight oil reservoir in Jinghe oil field,Ordos Basin,China

预测鄂尔多斯盆地西南部泾河油田长8地层致密油藏裂缝发育特征。针对研究区裂缝具有小规模、弱信息、突变和线性展布发育的特点,采用Likelihood算法对裂缝进行了预测和表征。研究表明:在垂直于裂缝方位的地震响应异常最明显,在确定裂缝方位和进行叠前方位数据处理的基础上采用Likelihood算法更加有效;在方位数据上提取的长8致密储层裂缝分布预测成果精度高,其发育位置及特性与实钻水平井钻遇裂缝段显示吻合度高。Likelihood算法是与研究区地质特性相匹配的地震裂缝预测技术。

Fractures are important to high production for Chang-8 tight reservoir, Jinghe oil field of Ordos Basin. Fracture are characterized and predicted by Likelihood algorithm so as to cope with the small scale, weak information, mutations and developmental characteristics of linear distribution in the study area. It shows that the seismic response at right angle to the fracture is obvious. The Likelihood algorithm is effective on the basis of determination of fracture orientation and process of pre-stack azimuth. The extracted results of fracture prediction from Chang-8 tight reservoir prove to be of high accuracy and the predicated fracture position and property are in agreement with drilling in horizontal wells. Therefore, seismic Likelihood fracture prediction technique matches with the geological characteristics of the study area.