Formation of carbonate fractured-vuggy reservoirs is controlled by palaeogeomorphology,tectonic movement and karstification.The main storage spaces are large-scale caves,small-scale dissolved pores and multi-scale fractures with different geometry.Because of complicated genetic mechanisms and highly discrete,traditional continuum reservoir characterization methods are difficult to apply directly.Based on the recognition and description of fractured-vuggy reservoir,we use the classification characterization method to characterize various reservoirs.Guided by karst genetic mechanisms and outcrops studies,in combination with seismic qualitative forecast and quantitative inversion results,we simulate weathering karst caves and faults-controlled caves using sequential indicator and the object-based method respectively.We use the method of collaborative sequential indicator simulation to establish the distribution model of the small scale dissolution pore.Based on the seismic information,we establish the multi-scale discrete fracturing network using the artificial interpretation,ant tracking and random simulation methods.Based on karst genetic mechanisms,we construct fusion principle for different types of reservoirs,and thus effectively integrated different types of reservoirs.The results show that the idea of the classification and characterization method can effectively describe the strong heterogeneity of S80 unit.Based on the model,we can refine the reserve classification in different the reservoir pay sections,evaluate the new well design,identify the target area,and apply it to the numerical simulation of reservoirs.The method lays the geological foundation to guide discovery of remaining oil potential,and modification of development plan.%碳酸盐岩缝洞型油藏受古地貌、构造及岩溶作用控制,储集体类型多样,主要以不同类型的大尺度溶洞、小尺度孔洞及多尺度裂缝为主,储集体成因机制不同,高度离散,传统连续性储层表征思路难以直接套用.以储集体识别和描述为基础,基于分类表征的思想对不同类型储集体分别进行刻画.以岩溶成因及野外露头为指导,综合地震定性预测与定量反演成果,对于风化壳成因、断控成因的大尺度溶洞分别采用序贯指示方法和基于目标的方法进行模拟.对于小尺度孔洞采用协同序贯指示模拟方法建模,对于多尺度裂缝则以地震信息为基础,采用人工解释、蚂蚁追踪与随机模拟相结合的方法进行表征.在分类表征基础上,根据岩溶成因规律构建分类储集体的融合原则,实现了分类模型的整合.结果表明:该方法能够有效表征S80单元缝洞型油藏的强非均质性特征,基于模型细化评价单元储量级别,设计新钻井位置,筛选有利目标区均取得较好效果,模型应用于油藏数值模拟,为指导剩余油挖潜与开发方案调整奠定地质基础.
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