【摘要】 在四川盆地北部地区,生物礁储层是重要的油气储集体且主要发育在上二叠统长兴组。由于其埋藏深,非均质性强,勘探风险大,常规的地震勘探技术虽然可以识别生物礁,但很难对生物礁是否具备储层条件以及储层中是否含有油气进行判别,需要利用叠前地震资料的AVO响应进行含油气性检测,以达到评价生物礁相油气藏的目的。首先介绍了AVO技术的理论基础Zoeppritz方程;其次选取四川盆地syb地区3个共偏移距数据体,用2口井作约束实施了AVO叠前反演,得到了一系列反演数据体;再根据生物礁含气储层的测井数据敏感性分析,最终确定了气藏最有利含气区带。研究结果为四川盆地生物礁油气藏勘探提供了目标。更多还原

【Abstract】 Biohermal reservoirs as the major set of units holding hydrocarbon reserves are found to be mainly developed in the Upper Permian Changxing Formation of the northern Sichuan Basin.However,their deep burial depth and strong heterogeneity result in a high exploration risk.Although conventional seismic exploration techniques can identify bioherms,it is still hard to further define reservoir quality and detect hydrocarbons.Therefore,pre-stack AVO responses are needed to detect hydrocarbons and to appraise the biohermal reservoirs.First,the Zoeppritz equation,the theoretical basis of AVO technique,is introduced.Then,three common offset data volumes are selected from the syb area in the Sichuan Basin.Pre-stack AVO inversion is performed under the constraint of 2 wells to obtain a series of inverse cubes.Finally,sensitivity analysis of logging data of gas-bearing biohermal reservoirs is carried out to define gas plays.Favorable exploration targets are identified for the biohermal gas reservoir exploration in the Sichuan Basin.更多还原