地震波形指示反演技术在埕海区块薄储层预测中的应用

Application of seismic waveform indication inversion technology in prediction of thin reservoir in Chenghai block

埕海区块是大港油田近年来油气增储建产的重要区块,已钻井资料证实该区块以构造背景下的岩性油气藏为主,油藏类型丰富,主要含油层系为沙河街组沙二段。受三角洲前缘沉积的影响,储层单砂层薄、横向变化快,导致该区储量探明程度较低,制约了数千万吨储量的有效动用。针对研究区薄储层的预测问题,传统的地质统计学随机反演方法在实际应用上存在模拟结果受井位分布影响大,反演参数难量化导致结果随机性强等问题。为此,采用地震波形指示反演技术开展薄储层预测,通过三维理论模型试算与实例应用对比显示,纵向上砂体的分辨较好,横向上地质沉积规律明显。

Chenghai block is an important block for increasing oil and gas reserves and production in Dagang Oilfield in recent years.Drilling data have confirmed that the block is mainly of lithologic oil and gas reservoirs under structural background,with rich reservoir types.The main oil-bearing series is the second member of Shahejie formation.Affected by the deposition of the delta front,the single sand layer of the reservoir is thin and changes rapidly laterally,resulting in a low degree of proven reserves in this area,which restricts the effective production of tens of millions of tons of reserves.For the prediction of thin reservoirs in the study area,the traditional geostatistical random inversion method has some problems in practical application,such as the simulation results are greatly affected by well location distribution and the inversion parameters are difficult to quantify,leading to strong randomness of the results.Therefore,the seismic waveform indication inversion technology is used to predict thin reservoirs.The comparison between the trial calculation of three-dimensional theoretical model and practical application shows that the resolution of sand body in the longitudinal direction is good and the geological sedimentary law in the transverse direction is obvious.