页岩储层无支撑缝网区流动能力影响因素研究与进展  

Research and progress on factors affecting the flow capacity in unsupported fracture network area of shale reservoir

作　　者：端祥刚[1,2] 胡志明 常进[1,2] 石雨昕 吴振凯[1,2] 许莹莹 DUAN Xianggang;HU Zhiming;CHANG Jin;SHI Yuxin;WU Zhenkai;XU Yingying(Research Institute of Petroleum Exploration&Development,Beijing 100083,China;Key Laboratory of Unconventional Oil&Gas Development,PetroChina,Langfang,Hebei 065007,China)

机构地区：[1]中国石油勘探开发研究院,北京100083 [2]中国石油非常规油气重点实验室,河北廊坊065007

出　　处：《特种油气藏》2025年第1期22-31,共10页Special Oil & Gas Reservoirs

基　　金：中国石油科技专项“页岩油气开发机理与体积开发技术研究”(2023ZZ08)。

摘　　要：针对页岩储层体积压裂缝网中无支撑缝网区的气液渗流特征及其对开发规律影响不清的问题,总结了国内外无支撑缝网体积、水岩作用、裂缝导流能力、气液两相流动等方面的研究进展,分析了无支撑裂缝导流能力的影响因素及其对储层产水产气能力的影响。研究表明:无支撑缝网区(包括无支撑人工缝、诱导缝及沟通的天然裂缝等)是沟通支撑裂缝和基质、大幅增加泄气面积的主体;无支撑裂缝受支撑条件、水岩作用及上覆应力等因素的影响,其导流能力和气水两相流动规律更复杂,对上覆应力变化也更敏感,随应力增加含水裂缝渗透率可下降2~4个数量级;页岩气开发过程中,无支撑缝网区的导流能力及演化规律是闷井返排制度设计和生产制度优化的关键。下步重点攻关方向主要包括无支撑裂缝气-液-固三相作用机理与微观力学机制、裂缝长期导流能力主控因素与气水两相流动模型,以及全生命周期缝网演化规律等方面。该研究成果可为页岩气闷井返排制度和生产制度的优化设计、保持气井长期高产稳产提供科学依据。To address of issue of the unclear understanding of the gas-liquid flow characteristics and the influence on development patterns within the unsupported fracture network in shale volume fracturing,the research progress on the volume of unsupported fracture networks,water-rock interaction,fracture conductivity,and gas-liquid two-phase flow both domestically and internationally are summarized.Meanwhile,the influencing factors of unsupported fracture conductivity and its impact on the water production and gas production capabilities of the reservoir are analyzed.The study indicates that the unsupported fracture network area(including unsupported artificial fractures,induced fractures,and connected natural fractures)is the major body that connects supported fractures with the matrix and significantly increases the gas leakage area.The conductivity and gas-liquid two-phase flow patterns of unsupported fractures are more complex due to factors such as support conditions,water-rock interaction,and overburden stress,and they are more sensitive to changes in overlying stress.The permeability of water-bearing fractures can decrease by 2 to 4 orders of magnitude with increasing stress.The conductivity and evolution patterns of the unsupported fracture network area during shale gas development are key to the design of the wellbore flowback system and the optimization of production systems,providing a scientific basis for maintaining long-term high and stable production of gas wells.The next key research directions mainly include the mechanism of gas-liquid-solid interaction and micromechanics in unsupported fractures,the main controlling factors of long-term fracture conductivity and gas-liquid two-phase flow models,as well as the evolution patterns of fracture networks throughout the entire life cycle.This research results can provide a scientific basis for the optimal design of wellbore flowback systems and production systems in shale gas development,ensuring long-term high and stable production of gas wells.

关 键 词：页岩 裂缝 水岩作用 无支撑裂缝 流动能力 缝网演化 

分 类 号：TE377[石油与天然气工程—油气田开发工程]