深部煤矿强矿震震源参数分析及震源机制研究  

Study on the internal relationship of source parameters and focal mechanism of strong mine tremors in deep coal mines

作　　者：吴坤波 邹俊鹏 焦玉勇 胡小悦 WU Kunbo;ZOU Junpeng;JIAO Yuyong;HU Xiaoyue(Faculty of Engineering,China University of Geosciences(Wuhan),Wuhan,Hubei 430074,China)

机构地区：[1]中国地质大学(武汉)工程学院,湖北武汉430074

出　　处：《岩石力学与工程学报》2023年第10期2540-2551,共12页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金重点项目(41731284);国家自然科学基金面上项目(42177152)。

摘　　要：我国煤炭资源开采逐渐走向深部,山东、内蒙等多个矿井大能量矿震频发,严重制约了煤矿的安全高效生产。对强震震源机制的解析是强矿震预警及防控的前提。通过深度剖析东滩煤矿63上06工作面回采过程中发生的27次强矿震事件,利用现场监测和理论分析手段对强矿震地震波形进行快速傅里叶变换(FFT)处理,采用Savage震源谱模型拟合获取拐角频率及低频位移幅值,分析强矿震震源参数间的关联性,揭示震源破裂尺度及破裂面产状特征。基于矩张量反演和破裂面产状计算,获取东滩煤矿强矿震震源机制解及破裂面产状,结果表明强矿震事件震源机制以剪切破坏为主、混合剪切破坏次之。煤层上覆厚硬岩层分别沿工作面推进方向及邻近采空区横向方向发生断裂错动,2种矿震诱发机制相互交叉、相互促进。煤层开采引起的上覆厚硬岩层剧烈运动及瞬时断裂从而释放大量应变能是导致强矿震事件频发的主要原因。As the coal resource exploitation gradually goes deeper,large-energy mine tremors occur frequently in several mines in Shandong and Inner Mongolia,which seriously restrict the productivity and effectiveness of mining activities.The focal mechanism analysis of seisms is the precondition for early warning and prevention and control of strong mine tremors induced by coal seam extraction.This paper provides an in-depth analysis of 27 strong mine tremors that occurred during the mining process of panel 63upper06 in Dongtan coal mine.The fast Fourier transform(FFT)method is employed to process the seismic waveforms of strong mine tremors by using field monitoring and theoretical analysis.The corner frequency and low-frequency displacement amplitude are obtained by fitting the Savage source spectrum model.The internal relationship between the source parameters of strong mine tremors is analysed,as well as the scale and occurrence of source rupture are calculated effectively.Based on the moment tensor inversion and occurrence of source rupture,the focal mechanism solutions of strong mine tremors are determined in Dongtan coal mine.The results show that the focal mechanism of these strong mine tremors is dominated by shear failure,followed by mixed shear failure.The overlying thick and hard rock strata above the coal seam are fractured and faulted along the advancing direction of the working face and the transverse direction of the adjacent goaf,respectively.We believe the two forming types of strong seisms cross each other and promote each other.The violent movement and instantaneous fracture of the overlying thick and hard rock strata caused by coal seam mining are the main reason for the frequent occurrence of strong mine seismic events.

关 键 词：采矿工程 深部矿井 强矿震 震源机制 震源参数 矩张量反演 PT投影 

分 类 号：TD32[矿业工程—矿井建设]