Research On Water Inrush Risk Of Double-aquifer Clipping Coal Seam

With the increasing depth of mining, North China coal mine water inrush accidents occur again and again, facing severe situation of water inrush risk.Water inrush caused by deep coal mining has two basic types: the inrush of roof water and the inrush of floor water. Kailuan Donghuantuo mine locating in Kaiping coal mine which is a part of North China coal basin has a very complex hydrogeology condition. And mine production has been threatened by the the end egg water of Fourth grade and the limestone karst water of Ordovician. So it is very important to study the law of roof and floor water inrush for ensuring safety production and making best use of coal resource.In this way, the thesis summarizes research methods and achievements of water risk of roof and floor in recent years systemataicly, collects and sorts out the materials of geology, hydrogeology and building wells in Kailuan Donghuantuo coal mine in recent years, elaborates the features of stratum, structure and coal seam in Donghuantuo mine through regional geology and mine field geology. The result shows that Kailuan Donghuantuo mine has a typical characteristic of North China Permo-Carboniferous coal mine.Then it analyzes mine hydrogeology conditions and the distribution characteristics of top aquifer and the underlying aquifuge for 12-2 coal seam at the background of the water inrush risk for coal 12-2 mining in Zhongyang-Beiyi mining area.And it studies the height of water flowing fractured zone and its distribution law and evaluated falling safety. Finally, it determines the partition of water abundance through the analysis of lithology field, construction field, seepage field and water chemistry field for coal 12-1～coal 12-2 aquifer and coal 12-2～coal 14-1 strong aquifer.In addition, it evaluats the water inrush risk of every floor aquifer from depth of destroyed floor, water burst coefficient and critical internal pressure according to some relevant theories and methods for the analysis of coal seam floor water inrush.The result shows that the height of water flowing fractured zone of coal 12-2 roof in Zhongyang-Beiyi mining area in Donghuantuo mine couldn't break top strong aquifers. the direct inrush risk is coal 12-1～coal 12-2 weak aquifer and its strength of water abundance reflects the risk of water inrush. And it is coal 12-2～coal 14-1 strong aquifer that could cause floor water inrush. In a word, it is very important to take reasonable and effective measures according to water inrush risk in different depth and areas of roof and floor for saft mining in this area to keep development of the whole coal mine.