Abstract： 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.
