煤矿老空水瞬变电磁响应特征数值模拟  

Numerical Simulation of Transient Electromagnetic Response Characteristics of Mine Gob Water

作　　者：常江浩[1] 于景邨[1] 蒋宗霖 

机构地区：[1]中国矿业大学资源与地球科学学院,江苏徐州221116 [2]中国煤炭科工集团西安研究院有限公司,陕西西安710077

出　　处：《矿业安全与环保》2014年第3期4-8,共5页Mining Safety & Environmental Protection

基　　金：国家重大科学仪器设备开发专项基金项目(2011YQ03013307)

摘　　要：煤矿老空区充水对后续煤矿安全生产威胁大。基于电磁场扩散理论,采用时域有限差分法,建立全空间二维地质模型,研究老空水瞬变电磁响应特征,结果表明:煤矿巷道中的激励源,不仅在巷道迎头前方岩体中激发二次感应场,而且在巷道迎头后方围岩中也激发二次感应场,极大值等值线环由激励源处分别向上、向下移动,强度逐渐减弱。矿井瞬变电磁场扩散速度受周围介质电性影响,低阻介质中扩散速度慢,高阻介质中扩散速度快,巷道迎头前方低阻体对全空间瞬变电磁场影响明显。当地质体中存在低阻体时,其附近电场等值线密集,梯度变大,扩散速度降低,涡流密度变大、衰减变慢。The water filling into the gob is seriously imperiling the follow-up production of a mine. Based on the diffusiontheory of electromagnetic field and by using the finite difference time domain method, a two-dimensional whole-space geologicalmodel was built and study was made on the transient electromagnetic response characteristics of gob water. The result showed thatthe incentive source in the mine roadway excited not only a secondary induction field in the rock mass in front of the roadwayhead, but also a secondary induction field in the surrounding rock behind the roadway head, the maximum contour loops movedupwards and then downwards from the incentive source, and their intensity gradually weakened. The diffusion velocity of the mineTEM field was affected by the electrical parameter of surrounding medium, it was slower in the low-resistance medium and fasterin the high-resistance one, the low-resistance body in front of the roadway head had an obvious influence on the whole-spaceTEM field. When a low-resistance body existed in the geologic body, the isoclines of the electric field near it became moreintensive, the gradient increased, the diffusion velocity reduced, the eddy-current density increased and the attenuation becameslower.

关 键 词：瞬变电磁法 老空水 响应特征 数值模拟 

分 类 号：TD745.21[矿业工程—矿井通风与安全] P613.8[天文地球—矿床学]