微震监测地质异常对工作面回采影响分析

Influence analysis of microseismic monitoring geological anomaly on working face mining

新集二矿属华北型煤田南部边缘,位于淮南煤田中区南部,新生界松散层下有120~800 m推覆体,外来推覆构造覆盖于原石炭—二叠含煤地层之上,推覆体很大程度上阻隔了新生界松散层与二叠系煤系地层和下伏隔含水层的水力联系,形成了矿井独特的水文地质条件。本文以230102工作面为例,采用微震监测技术手段,监测过断层期间微震响应,分析底板事件发育情况,以及揭露断层对回采工作面的影响,判断断层是否活化,是否形成垂向导水通道,进行底板灰岩水害微震监测预警。结果表明,老人仓断层、采掘揭露的断层均未发生活化,未形成有效垂向导水通道。

Xinji No.2 Mine was located in south centre zone of huainan coalfield,being part of south margin in north china type coal field.There was 120~800 meters nappe under cenozoic loose layer,foreign nappe structure covered primary Carboniferous-Permian coal-bearing strata,nappe interrupted the hydraulic connection between Cenozoic loose strata,Permian coal measures strata and underlying aquifer,aquifuge to a great extent,which formed the unique hydrogeological condition of the mine.This paper took No.230102 working face as an example,technical means of microseismic monitoring was used,microseismic response was aimed to be monitored during passing through fracture,event development under the floor was analyzed,the influence of fracture on working face was exposed,fracture activation and the formation of water conducting channel in vertical direction were determined,early warning of floor limestone water damage by microseismic monitoring was in progress.The results showed that Laorencang fracture and fracture exposed by mining and excavating had not generated activation,significant water conducting channel in vertical direction had not formed.