深层裂缝性储集层封堵层结构失稳机理与强化方法  

Structural failure mechanism and strengthening method of plugging zone in deep naturally fractured reservoirs

作　　者：许成元[1] 闫霄鹏 康毅力[1] 游利军[1] 张敬逸 XU Chengyuan;YAN Xiaopeng;KANG Yili;YOU Lijun;ZHANG Jingyi(State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu 610500,China)

机构地区：[1]油气藏地质及开发工程国家重点实验室西南石油大学,成都610500

出　　处：《石油勘探与开发》2020年第2期399-408,共10页Petroleum Exploration and Development

基　　金：国家自然科学基金“基于逾渗和固液两相流理论的裂缝性储层工作液漏失损害预测与控制”(51604236);四川省科技计划项目“保护储层并改善优势天然裂缝导流能力的钻井预撑裂缝堵漏基础研究”(2018JY0436);非常规油气层保护四川省青年科技创新研究团队项目(2016TD0016)。

摘　　要：针对深层裂缝性储集层工作液漏失控制问题,以颗粒物质力学为基础,明确了裂缝封堵层多尺度结构,构建了深层裂缝性储集层高温、高压、高地应力环境下裂缝封堵层失稳模式,揭示了封堵层结构失稳机理。基于裂缝封堵层强度模型,提取了堵漏材料关键性能参数,选用新型堵漏材料开展室内实验,评价了材料关键性能参数对裂缝封堵效果的影响,最终形成了深层裂缝性储集层堵漏材料选择原则。研究表明,裂缝封堵层承压过程中,堵漏材料相互接触形成力链网络,决定宏观封堵层承压稳定性。摩擦失稳和剪切失稳为裂缝封堵层结构主要失稳模式。细观力链强度取决于微观尺度堵漏材料性能,粒度分布、纤维长径比、摩擦系数、抗压能力、抗高温能力、可溶蚀能力为堵漏材料关键性能参数。室内实验和现场试验结果表明,根据所提取的关键性能参数优选堵漏材料,可有效提高深层裂缝性储集层漏失控制效果。Focused on the lost circulation control in deep naturally fractured reservoirs,the multiscale structure of fracture plugging zone is proposed based on the theory of granular matter mechanics,and the structural failure pattern of plugging zone is developed to reveal the plugging zone failure mechanisms in deep,high temperature,high pressure,and high in-situ stress environment.Based on the fracture plugging zone strength model,key performance parameters are determined for the optimal selection of loss control material(LCM).Laboratory fracture plugging experiments with new LCM are carried out to evaluate the effect of the key performance parameters of LCM on fracture plugging quality.LCM selection strategy for fractured reservoirs is developed.The results show that the force chain formed by LCMs determines the pressure stabilization of macro-scale fracture plugging zone.Friction failure and shear failure are the two major failure patterns of fracture plugging zone.The strength of force chain depends on the performance of micro-scale LCM,and the LCM key performance parameters include particle size distribution,fiber aspect ratio,friction coefficient,compressive strength,soluble ability and high temperature resistance.Results of lab experiments and field test show that lost circulation control quality can be effectively improved with the optimal material selection based on the extracted key performance parameters of LCMs.

关 键 词：深层 裂缝性储集层 井漏 裂缝封堵层 多尺度结构 强度稳定性 堵漏材料 

分 类 号：TE28[石油与天然气工程—油气井工程]