深层页岩储层裂缝识别及有效性评价方法研究及应用——以四川盆地南部为例  

Research and application of fracture identification and effectiveness evaluation methods for deep shale reservoirs:A case study in southern Sichuan Basin

作　　者：邱小雪 石学文 廖茂杰 张洞君 高翔 杨杨 钟光海 刘鹏 QIU Xiaoxue;SHI Xuewen;LIAO Maojie;ZHANG Dongjun;GAO Xiang;YANG Yang;ZHONG Guanghai;LIU Peng(Shale Gas Research Institute,PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan 610051,China;Research Institute of Petroleum Exploration and Development,CNPC,Beijing 100083,China)

机构地区：[1]中国石油西南油气田公司页岩气研究院,四川成都610051 [2]中国石油勘探开发研究院,北京100083

出　　处：《油气藏评价与开发》2025年第1期40-48,55,共10页Petroleum Reservoir Evaluation and Development

基　　金：中国石油科技项目“新区新层系有利区优选与勘探评价关键技术研究”(2023ZZ21-04)。

摘　　要：四川盆地南部地区(以下简称川南)深层页岩储层断裂发育,直接影响页岩气水平井的工程施工和有效建产。基于川南五峰组—龙马溪组页岩岩心,开展岩石物理实验和数值模拟实验,得到了不同尺度、不同产状、不同充填物质的裂缝声学响应特征,分析了裂缝对声波衰减能力的影响因素,建立了1套页岩气水平井裂缝识别和有效性评价方法。结果表明:纵波、横波和斯通利波的振幅衰减受裂缝倾角和裂缝宽度的共同影响,其衰减能力随裂缝宽度增加呈指数增加,随裂缝倾角的增加而降低。斯通利波对充填流体裂缝敏感,可识别和评价含气、含水的有效裂缝;纵波和偶极横波对充填方解石裂缝敏感,可识别和评价充填方解石的无效裂缝。基于反射波成像识别的裂缝结果与成像测井、岩心识别裂缝类型一致,验证了有效性评价方法的可靠性。将研究成果应用于页岩气水平井实测资料,精细评价了页岩气水平井断裂风险位置,有效保障了“一段一策”压裂分段的优化设计。In the deep shale reservoirs of the southern Sichuan Basin,the development of fractures directly impacts the engineering construction and effective production of horizontal shale gas wells.Taking the shale cores in the Wufeng-Longmaxi Formation in the southern Sichuan Basin as a case study,rock physics experiments and numerical simulations were conducted to obtain the acoustic response characteristics of fractures at different scales,orientations,and fillings.The study analyzed the factors affecting the attenuation capability of acoustic waves on fractures and established a set of fracture identification and effectiveness evaluation methods for horizontal shale gas wells.The results showed that the amplitude attenuation of P-waves,S-waves,and Stoneley waves was influenced by both the fracture dip angle and fracture width,with attenuation capacity exponentially increasing with fracture width and decreasing with the dip angle.Stoneley waves were sensitive to fluid-filled fractures and could be used to identify and evaluate gas-bearing and water-bearing effective fractures.P-waves and dipole S-waves were sensitive to calcite-filled fractures,able to identify and evaluate ineffective calcite-filled fractures.The fracture identification results based on reflected wave imaging were consistent with the results obtained from imaging logging and core identification,verifying the reliability of the effectiveness evaluation method.The research findings were applied to the actual data from horizontal shale gas wells,thoroughly evaluating the fracture risk positions in horizontal shale gas wells and effectively ensuring the optimized and tailored design for fracturing segments.

关 键 词：裂缝 深层页岩 阵列声波 振幅衰减 有效性评价 

分 类 号：TE319[石油与天然气工程—油气田开发工程]