三维叠前深度偏移技术在潜山成像中的应用

Application of 3D pre-stack depth migration in the imaging of buried hill

（1．中国石油化工股份有限公司石油勘探开发研究院南京石油物探研究所,江苏南京210014；2．中国石油化工股份有限公司胜利油田分公司物探研究院，山东东营257022）

Institute of Geophysical Prospecting,Research Institute of Petroleum Exploration and Development,SINOPEC,Nanjing 210014,China

孤西潜山带地质构造复杂，埋藏深，地震资料信噪比低，准确成像困难。采用三维叠前深度偏移方法对孤西潜山带的连片常规三维地震资料和高精度三维地震资料进行了重新处理。对各区块数据在频率、相位、信噪比和覆盖次数等方面的差异进行了归一化、匹配滤波和剩余能量补偿等处理；基于叠前时间偏移进行了速度分析，参考井速度和合成地震记录，建立了初始速度模型；对偏移参数进行了测试和选取，采用Kirchhoff积分叠前深度偏移方法对资料进行了偏移处理。结果表明，叠前深度偏移提高了地质构造复杂地区的成像质量，断层和潜山内幕反射清晰，层位深度与钻井深度吻合较好，发现了新的有利构造。

Guxi buried hill zone is characterized by complex structures,deep buried reservoirs,low S/N in seismic data,it is difficult for accurate imaging.3D pre-stack depth migration was used to reprocess the merged 3D conventional seismic data and 3D high-precision seismic data.The difference on frequency,statistical phase,S/N and fold of the data from all blocks was processed by normalization,matched filtering and residual energy compensation.Velocity analysis was carried out based on prestack time migration,initial velocity model was established with the velocity of reference well and synthetic seismogram.Migration parameters were tested and selected.Kirchhoff integral prestack depth migration was used to process the data.The results showed that pre-stack depth migration improved the imaging quality for the area with complex structures,the reflection of fault and inner buried hill was clear,the horizon depth coincided well with drilling depth,and new favorable structure was discovered.