泌阳凹陷孙岗地区水下分流河道地震识别及预测

Seismic Recognition and Prediction of Underwater Distributary Channels in Sungang Area of Biyang Sag

在分析研究区水下分流河道成因的基础上,利用高分辨率三维地震资料所揭示的地震反射波同相轴外部反射构型和内部反射结构特征进行水下分流河道反射外形识别。提取了目的砂层组地震反射波层间或沿层的瞬时振幅、瞬时频率、瞬时相位、均方根振幅、平均绝对振幅、平均反射能量、瞬时频率的斜率、能量半衰时斜率、弧长、平均反射强度以及沿层相干等属性。通过多属性联合对比以及井震结合,最终确定利用均方根属性切片预测水下分流河道空间展布。研究表明,该区水下分流河道在地震剖面上可识别出垂向加积、侧向迁移和透镜体叠置等3种典型反射特征。水下分流河道自东北部向西南部呈指状大面积延伸。钻探证实了此项研究结果,为泌阳凹陷油气勘探开辟了新的领域。

In order to effectively predict lithological reservoir position, Based on analysis of the origin of the underwater distributary chan- nel in study area, and the seismic reflection configuration of the underwater distributary channel has been recognized using the reflection features of seismic event from the high resolution 3D seismic data. Then many interlaminar or along-horizon attributes of the seismic reflec- tion wave of the interested sand group are extracted, including instantaneous amplitude, instantaneous frequency, instantaneous phase, root- mean-square （RMS） amplitude, mean absolute amplitude, mean reflection power, instantaneous frequency slope, slope at half-life energy, arc length, mean reflection strength and lateral coherent feature, etc. By the multi-attribute combined correlation and the log-seismic data integration, it is finally determined to predict the spatial distribution of underwater distributary channel sand bodies using RMS attribute sections. The research shows that three typical reflectance features of vertical accretion, lateral migration and sand lens superimpostion, have been recognized onthe seismic profile. The underwater distributary channel sand bodies appear large scale finger-shaped extension from the NE to the SW. The studied results have been confirmed by the drilling responses, which opens a new field of oil and gas explora- tion in Biyang sag.