碳酸盐岩溶洞型储集体地震检测的累计能量差方法

Accumulative energy difference method for detecting cavern carbonate reservoir by seismic data

在新疆塔河油田碳酸盐岩储层中,溶洞型储集体是油气的主要储集空间。溶洞型储集体在纵、横向上均具有较强的非均质性,在地震剖面上表现为"串珠状"反射特征。若能通过地震资料对溶洞进行有效检测,对于提高钻探成功率、降低勘探风险具有实际意义。为此,提出了一种新的溶洞检测方法——累计能量差法,即利用道内或道间地震反射能量上的差异进行溶洞检测。首先讨论了地震波场累计能量差的计算原理;然后通过建立溶洞系统的理论模型,利用地震正演对方法的应用基础进行了验证,并利用无噪和含噪的正演记录对检测参数进行确定。新疆塔河托普台油田实际资料的应用结果表明,累计能量差法能很好地识别和检测出碳酸盐岩储层中溶洞的发育位置和特征。

Cavern carbonate reservoir is the main reserve space of Tahe oilfield in Xingjiang,which has strong vertical and lateral heterogeneity and shows string-bead reflection on seismic profile.If we can effectively detect the caverns by seismic data,it will have practical significance for enhancing the success ratio of oil-gas exploration. Therefore,a new cavern detection technique called accumulation energy difference method was proposed,which uses the seismic reflection energy difference in trace or between traces to detect caves. Firstly,the calculation principles for accumulative energy difference of seismic wave fields were discussed.Secondly,the seismic forward modeling was carried out on the established theoretical model of cavern system to confirm the application foundation of this method. The reasonable detection parameters were determined by different models with or without noise.The practical application to Tahe TPT oilfield of Xingjiang shows that the accumulative energy difference method can well distinguish and detect the position and characteristic of cavern in carbonate reservoirs.