浅水三角洲砂体预测的地震属性方法探讨

浅水三角洲砂体是渤海海域新近系良好的油气储层，但在新三维地震工区少井条件下浅水三角洲砂体与地震响应关系有待完善，砂体的精细刻画存在一定困难。在高频层序划分的基础上，针对黄河口凹陷X 工区各准层序组砂体如何展布的问题，展开了对X 工区明下段下亚段岩性组合与地震属性的对应关系研究，研究中采用正演模拟建立起砂体地质地球物理模型，然后利用90? 相移后的均方根属性对明下段下亚段pss1 pss11 层序砂体进行了细致刻画，研究结果表明，地震剖面中振幅的强弱能够直接反映砂体的发育情况，强振幅反映了砂体较厚（或对应复合厚互层）、中强振幅一般对应大套泥岩夹厚层中等厚度砂岩、弱振幅反映了砂体不发育。砂体预测结果与实钻井对比吻合良好，说明少井条件下利用特定的地震属性预测浅水三角洲砂体的可行性。

Seismic Attribute Analysis of Shallow-water Deltaic Sand Body Prediction

The shallow-water deltaic sand body is excellent reservoir in Neogene strata of the Bohai Bay. However，as there is alack of well data in the new 3D seismic survey，the relation between the shallow-water deltaic sand bodies and seismic responsesis still obscure. It is difficult to depict the sand bodies precisely. In order to discuss the parasequence sand body distribution inwork area X in Huanghekou sag，this paper summarizes the relationship between the lithological combinations and the seismicattributes in lower Minghuazhen submember ，based on the high-frequency sequences division. Using the seismic forwardmodeling，the we establish the geophysical model of sand bodies and depicts the pss1 pss11 level sequence sand bodies ofMinghuazhen submember in a deliberate way，by making use of RMS amplitude attributes of 90? phase conversion seismicdata. The result proves the relationship between the amplitude of seismic profiles and sand body concentration. The high RMSamplitude figure demonstrates the thick sand bodies（or the corresponding compound thick level）. The middle amplitude figurenormally corresponds to massive mudstone clipping thick-middle thick sandstones，and low amplitude figure shows the barelydeveloped sand bodies. These results match noticeably with the well drilling s data. Therefore，it is feasible to predict theshallow-water deltaic sand body by using the seismic attributes.