奥陶系碳酸盐岩储层的储集空间主要为孔隙、裂缝和溶洞.缝洞体在地震剖面上的响应特征主要表现为"串珠"状的反射.近年来的勘探实践表明,准确识别这些"串珠"边界及空间位置,是准确刻画这些缝洞体的关键.结合理论模型,重点分析当前广泛应用于成像处理的Kirchhoff叠前时间偏移、Kirchhoff叠前深度偏移、逆时深度偏移(RTM)技术对缝洞体成像效果的差异.根据正演模型与实际资料处理效果分析,相对Kirchhoff叠前时间偏移,Kirchhoff叠前深度偏移与逆时深度偏移都能得到正确的空间位置,逆时深度偏移聚焦效果最好.%The reservoir space of the Ordovician System carbonate reservoir is mainly consist of pore, fracture and cavity. Response characteristics of the fracture and cave system on the seismic profile is mainly "beaded" reflection. In recent years, the exploration practice indicates that accurate recognition of these "beaded" boundary and space position, is the key to accurately depict the fracture cave system. Combined with the theoretical model, we focused on the analysis of different techniques of Kirchhoff prestack time migration, Kirchhoff prestack depth migration and reverse-time depth migration (RTM) which were widely used in the imaging processing for fracture and cave system imaging. According to the analysis on forward model and actual data, we found that Kirchhoff prestack depth migration and reverse-time depth migration both can get the correct spatial location, compared with Kirchhoff prestack time migration. Moreover, the reverse-time depth migration gets best effect of focus.
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