渤海海域浅层岩性勘探新进展与勘探关键技术

New progress and key techniques of shallow lithologic reservoir exploration in Bohai Sea

随着勘探程度的提高,渤海海域浅层规模型构造圈闭已经钻探殆尽,向岩性勘探转移势在必行。但浅层岩性勘探在规模型砂体展布、油气富集模式、薄层砂体边界精细刻画及烃检等方面仍面临诸多问题与挑战。基于全覆盖三维地震资料和分析化验资料,开展了浅层区域沉积格局和油气成藏规律研究,明确了迁移型曲流河、稳定型曲流河、河-湖交互沉积发育模式及规模型砂体分布规律,建立了高凸起区、低凸起区、凹中隆起区和洼陷区4类浅层大面积岩性油气富集模式,同时创新形成井震匹配高分辨率波阻抗反演的砂体描述技术和基于频变AVO特征差异的综合烃类检测技术,推动了渤海海域浅层大面积岩性勘探获得重大突破,发现了垦利6-1、垦利10-2、渤中19-2和秦皇岛27-3等大中型油田。系统总结渤海海域浅层岩性勘探成果,以期对陆相断陷盆地浅层规模型岩性油气藏勘探起到借鉴作用。

With the petroleum exploration deepens,the shallow large-scale tectonic traps in the Bohai Sea have been discovered mostly,and the shift to lithologic exploration is imperative.However,shallow lithologic reservoir exploration faces issues and challenges in terms of large-scale sand distribution,hydrocarbon accumulation models,fine description of thin sand boundaries,and hydrocarbon detection.Based on the full-coverage 3D seismic data and experimental data,the shallow regional sedimentation patterns and hydrocarbon accumulation were investigated.The migration-type meandering river,stable-type meandering river,river-lake reciprocal sedimentation model,and large-scale sand distribution patterns were clarified.Four large-scale shallow lithologic hydrocarbon accumulation models were established in high-uplift,low-uplift,uplift area in depressions,and sag areas.Additionally,innovative techniques about well-seismic matching high-resolution wave impedance inversion for sand description and comprehensive hydrocarbon detection based on frequency variation AVO characteristics were developed.Based on the above achievements,major breakthroughs were obtained in shallow large-scale lithologic reservoir exploration in the Bohai Sea,and large-medium oilfields such as KL6-1,KL10-2,BZ19-2,and QHD27-3 were discovered.This study summarized exploration achievements of shallow lithologic reservoirs in the Bohai Sea systematically,to provide references for further exploration of large-scale lithologic reservoirs in terrestrial rift basins.