论文详情
塔河油田西部白垩系舒善河组砂岩具有良好的油气显示和勘探开发潜力。受制于单砂体厚度薄、砂泥互层频繁、沉积微相变化快等特点,以往常用的“振幅找油”技术存在一定的多解性,储层和流体分布预测难度大。在A井区进行了双相介质油气检测技术的探索性应用研究,在对已知油气层进行精确标定和层位解释的基础上开展了多时窗频谱分析试验,确定了最佳时窗和高、低频敏感段。因油气层是典型的双相介质,对应的地震波具有“低频能量增强,高频能量衰减”的特性,低频段与高频段的能量之比可以较好地反映地层中油气的富集程度,同时兼顾频谱中频段相对凸起的特征。应用结果表明,A井区的检测结果与已知油气井的符合率约为94.4%,高于振幅属性72.2%的符合率,说明该技术在本研究区是适用的,再结合其它成果进行综合分析,可更准确地预测潜在的有利目标区。
Abstract: The sandstone of the Cretaceous Shushanhe formation in the western Tahe Oilfield has oil and gas that show considerable potential for exploration and development.The commonly applied amplitude oil search method cannot be used in this formation due to its thin sand,frequent sand and mud interbed,and rapid changes in its sedimentary microfacies,so accurately predicting reservoir and fluid distribution in this area is difficult.To more accurately their distribution,we exploratively applied two-phase medium oil and gas detection technology in the A well area of the Tahe Oilfield.Based on an accurate well-seismic calibration and horizon interpretation of the known oil and gas reservoirs,we conducted a multiwindow spectrum analysis test,through which we determined the optimal time window and sensitive high- and low-cut frequency bands.Because the oil and gas reservoir is a typical dual-phase medium,the corresponding seismic waveforms have the typical characteristics:low-frequency energy enhancement and high-frequency energy attenuation.The energy ratio of the low- and high-frequency bands qualitatively reflected the degree of oil and gas enrichment in the formation.By examining the results obtained with the fluid detection technique,we found that the coincidence rate between the fluid detection results of the A well area and known oil wells was 94.4%,which is higher than the coincidence rate of the amplitude attribute of 72.2%,proving the effectiveness of the method in detecting fluid and that it can be used to predict favorable oil-bearing reservoirs.