Carbonate is one of the most important targets of hydrocarbon exploration in Tarim. Ordovician carbonate in Yubei area distributes widely with large thickness,and its exploration prospect is excellent. However, the exploration degree is low. The surface is desert with rugged sand dunes and deep buried target intervals, which is characterized by strong heterogeneity,rapid longitudinal and lateral variation,unclear seismic response, so the reservoir is difficult to predict. Therefore, by integrating multi-logging and core data, the reservoirs were classified. By crossplot analysis, the petrophysi-cal characteristics of reservoirs and host rock were analyzed. By seismic attributes extraction and forward modeling, the seismic responses of carbonate reservoirs were studied, and some seismic attributes were identified as the sensitive parameters for reservoir prediction (wave impedance, amplitude, amplitude variation ratio, coherence). Caves larger than 10 m shows strong-amplitude string reflection, which can be predicted by using conventional seismic data volume for extracting amplitude and its variation ratio. Fractured and cavern reservoirs to some thickness and scale may lead to obvious variation of seismic amplitude, which can be effectively predicted by utilizing conventional seismic data volume for extracting amplitude , its variation ratio and coherent attribute combining with wave impedance inversion.%玉北地区奥陶系碳酸盐岩分布范围广、厚度大,油气勘探前景良好,但目的层埋藏深,储层非均质性强,纵、横向变化快,储层地震响应特征不清晰,预测难度大.为此,应用该区测井数据和岩心、录井等资料对储层进行了分类,利用交会分析技术分析了储层与围岩的岩石物理特征,通过地震属性提取与模型正演,研究了碳酸盐岩储层的地震响应特征,确定了波阻抗、振幅、振幅变化率、相干等地震属性参数为储层预测的敏感参数.其中波阻抗对储层物性的变化比较敏感,对规模储层有较好的反映.10 m以上的溶洞产生强振幅串珠状反射,利用常规地震数据体提取振幅及振幅变化率可以进行有效预测；有一定厚度、规模的裂缝型、溶孔型储层能引起地震振幅的明显变化,利用常规地震数据体提取振幅及振幅变化率、相干属性,结合波阻抗反演可以进行有效预测.
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