摘要
水力压裂厚硬顶板的裂缝扩展效果,是评估该技术防冲性能的关键所在。以20101工作面厚硬岩层顶板水力压裂工程作为背景,运用地面微震监测技术以及最小体积覆盖椭圆球法,针对水力压裂过程中裂缝的扩展规律展开研究。结果表明:在总压裂长度为1000 m的范围内,总共监测到1255个微震事件;裂缝扩展范围与压裂液用量呈正相关,与压裂施工时间并无关联,且随着微震事件增加,厚硬岩层裂缝扩展范围增大;②以水平井为中心,水力压裂裂缝水平南北方向平均半径、水平东西方向平均宽度和垂直方向平均半径分别为127、71和31 m,水力压裂后厚硬岩层裂缝扩展体积(SRV)为371.2×10^(4)m^(3);③井下疏水孔钻场出水情况与地面微震监测裂缝扩展结果较为相符。研究结果表明地面微震监测技术能够用于水力压裂裂缝扩展效果的评估,可为该类条件下顶板水力压裂的裂缝评估以及防冲效果分析提供科学依据。
The fracture propagation effect in thick-hard roof strata during hydraulic fracturing is critical for evaluating the technology’s effectiveness in preventing rock bursts.Taking the hydraulic fracturing operation in the thick-hard roof strata of the 20101 working face as an engineering case study,we investigated the fracture propagation through surface microseismic monitoring and the small-volume covering ellipsoid method.The results demonstrate that:Firstly,within the total fracturing length of 1000 m,a total of 1255 microseismic events were monitored.The fracture propagation range is positively correlated with the volume of fracturing fluid used but unrelated to the fracturing operation time.As the number of microseismic events increases,the fracture propagation range in the thick-hard rock layer expands.Secondly,centered on the horizontal well,the average radii of hydraulic fractures in the north-south horizontal direction,east-west horizontal direction,and vertical direction are 127 m,71 m,and 31 m,respectively.The stimulated reservoir volume(SRV)after hydraulic fracturing of the thick-hard rock layer is 371.2×10^(4) m^(3).Thirdly,the water discharge observed at the underground drainage borehole sites is generally consistent with the fracture propagation results from surface microseismic monitoring.These findings confirm that surface microseismic monitoring technology is effective to evaluate the fracture propagation effectiveness of hydraulic fracturing,providing a scientific basis for fracture assessment and rockburst prevention effect analysis under similar conditions.
作者
姚子涛
陆闯
王宾昌
杨光宇
张晨阳
YAO Zitao;LU Chuang;WANG Binchang;YANG Guangyu;ZHANG Chenyang(China Coal Shaanxi Energy and Chemical Group Co.,Ltd.,Yulin 719000,China;Coal Mining and Designing Department,Tiandi Science and Technology Co.,Ltd.,Beijing 100013,China;CCTEG Coal Mining Research Institute,Beijing 100013,China;Key Laboratory of National Mine Safety Supervision Bureau for Mine Roof Disaster Prevention and Control,Beijing 100013,China;China Coal Shaanxi Yulin Energy and Chemical Co.,Ltd.,Yulin 719000,China)
出处
《煤炭工程》
北大核心
2026年第2期85-92,共8页
Coal Engineering
基金
中煤集团重大科技专项(20211BY001)。
关键词
水力压裂
微震监测
裂缝扩展
厚硬顶板
冲击地压
hydraulic fracturing
microseismic monitoring
fracture propagation
thick-hard rock strata
rock burst
