Study On Water-filling Characteristics Of 4^-2 Coal Seam In The First Panel Of The North Of Hong Liulin Coalmine

Hong Liulin coalmine is a large modern mine invested by Shaanxi coal and chemical industry group in Shenfu mining area.Its actual production capacity is 20 million tons per year.In August 7,2016,during the tunneling of the 24209 working face in the first panen of the north of the mine,water inrush occurred because the roadway directly revealed the weathered bedrock fissures of the coal seam roof,and the roadway was forced to stop tunneling to the present.It is found that the research degree of water-filling conditions of 4-2 coal seam is low in the first panen of the north of the mine,which can not meet the requirements of the mine safety and high efficiency mining on the research degree of the mine hydrogeological conditions.In this paper,taking the water-filling characteristics of 4-2 coal seam in the first panel of the north of Hong Liulin coalmine as the studied object,by collecting the water inrush data in the study area and the surrounding mines,combined with the hydrogeological supplementary exploration projects of the 4-2 coal seam in the study area,adopting the theoretical and technical methods of hydrogeology,hydrogeochemistry,mine geology,petrology and statistics,the water-filling source and water-filling channel during the mining of 4-2 coal mining are systematically analyzed and studied,and the hydrogeological characteristics of the main water-filling layers are emphatically analyzed and studied,and the hydrochemical database of the study area is set up.The conclusions are as follows:? During the mining of 4'2 coal seam,the direct water-filling source is Jurassic coal measures bedrock water,and the main water-filling layer is the weathering zone of coal and rock stratum of the roof,and the indirect water-filling source is Quaternary loose layer water,which has a weak water abundance.The coal seam roof losts Sarawusu formation and Zhiluo formation.The water-filling channel is water-conducting fissure zone,which can run through the whole roof bedrock and ends in the Baode formation.? the 4-2 coal seam and its roof bedrock all have weathering and burning phenomenon in different degrees.The southeast part of the 4-2 coal seam is weathered and eroded,while the 4-2 coal seam becomes completed gradually in the northwest part.The isoline of the roof bedrock thickness is similar to the form of an ancient gully.The ancient gully developed before the Jurassic Yanan formation after the Neogene Baode formation,which was near north and south direction and north by west,and the bedrock thickness in the middle of the gully was small,and the bedrock thickness on both sides of the ancient gully became large gradually.? The fissure in the weathering zone of coal and rock stratum of 4-2 coal seam roof is developed,but the fracture connectivity is poor,and the water abundance is very uneven.The water abundance of the coal seam weathering zone is better than the rock stratum weathering zone.The ancient gully has obvious water control effect on the roof coal and rock stratum of 4-2 coal seam.Its weathering fissure is developed and the connectivity is good in the middle of the ancient gully.While the development of the weathering fissure became poor in the east and west sides of the ancient gully,and the water abundance and permeability became weak obviously.? The water quality types in the weathering zone of coal and rock stratum of 4-2 coal seam roof is HCO3-Ca Mg,which belongs to low alinity water.Its water quality types and salinity are similar to the shallow loose layer water,and the content of organic matter is in accordance with the surface water and drinking water.? There is a clear hydraulic connection between the weathering zone water of the 4-2 coal seam roof and the water inrush point at the 24209 working surface.Vertically,the weathering zone water of the 4-2 coal seam roof accepts the recharge of the shallow loose layer water converted from the atmospheric precipitation or surface water.On the plane,the groundwater seepage field of the weathering zone water of the 4-2 coal seam roof moves from the northwest to the southeast.? The mine water prevention and control measures is put forward,and it contains the exploration measures of dewatering test and surveying and releasing water and ground hydrogeological supplementary exploration,and it also contains the control measures of avoiding mining and forced drainage and grouting water plugging.