G油田古近系重力流水道相储层预测研究

重力流水道砂体多分布于半深湖、深湖的暗色泥岩中,具有良好的成藏条件,但其厚度小,分布零散,埋藏深度大,预测困难。以G油田主要开发层位沙一中、下亚段为研究目标,该区重力流水道砂体广泛分布,具有泥包砂的沉积特点,岩性致密,物性较差,属典型超高压深层低渗透油藏。在借鉴区域研究成果的基础上,通过岩心、测井、地震基准面旋回识别,建立高精度等时地层格架;通过地震统计分析,利用测井资料和井旁地震数据,估计子波振幅谱和相位谱,并用最小平方法提取子波,进行精细标定,落实层面和断层解释;利用LandMark软件Poststack模块,选取具有代表性的地震波形作为学习样板,进行波形结构分析。针对测井约束反演存在多解性的缺点,提出相控反演的思路,通过多种资料的综合来建立初始波阻抗模型,这种初始波阻抗模型的优点在于更接近实际地质情况,能够剔除非储层区的干扰,可以从宏观上反映出目的层段的沉积相展布形态。基于此模型进行反演,更易于预测储层分布范围,更易于对层内砂体进行解释、追踪,刻画出小层内砂体的分布特征。

Study on Reservoir Prediction of the Paleogene Gravity Flow Channel in G Oilfield

Sand body of the gravity flow channel distributes in dark mudstones of half-deep and deep lake mostly,which has good reservoir-forming conditions but is hard to forecast for thin layers,scattered distribution and deep burial depth.The main producing position,middle-lower Sha 1 member of the G oilfield is studied.Sand body of the gravity flow channel in this area belongs to deep and low-permeability oil reservoir at ultrahigh pressure with the characteristics of wide distribution,sedimentation of sand in mud...