A Study On The Engineering Geology Characteristics And On Reasonable Scale Of Pillars For Protecting Water About The Overlying Strata Of Mining Coal Seam In Wugou Coalmine

About 270 meter thick unconsolidated formation was covered the main picked coalmine, especially Quaternary sand,gravel aquifer whose bottom are average thick of 20.7 meter are covered on the basset of exploit coal, which directly proceed alimentation and permeated to coal-measure unit ,what made clearly hazard of safety exploit of superficial part coal seam. Through actual measurement and systematically acquisition of data information, analyzing the lithological character, thickness, the hydrological characteristic, permeability of "3rd aquifuges "" 4th aquifers ", the bedrock weathering zone and so on in Wugou mine field , it was obtained in the paper that the level(group) clay soil of "3rd aquifuges" ,which in the region and the coal mine is important confining (group) , plasticity was well, expansion was strong , thickness was big, the distribution was stability, water separating character was good; " 4th aquifers " was directly covered above the coal formation stratum, which is the main supplies water source of mine, but because its "lithological character" are high argillaceous , permeability is badly ,the supplies condition is worse, general aqueous is weak; The bedrock weathering zone rock layer belongs to the weak medium -hard rock layer which also is the father from the coal bed roof, the weaker of the mudstone and the sandstone intensity presents, rock roof on the subordinate is upside hard and lower part soft that is advantageous for the roof control, Wugou coal mine the bedrock weathering zone rock layer above the principal work face has the dual function with reservoir water and separating water;The coal generated environment of 10₂ coal seam in mine principal pick of Wugou coal is the Strand plain moss- land precipitation facies, becomes the coal function after 10₂ coal beds to stop, delta system deposition widespread advancement, then to distributary channel sand body, The coal bed roof by the mudstone, the siltstone primarily, the granulated substance shape changes with the thin belt of 10₂ coal beds basically, the preliminary analysis which is washes out by old channel to 102 coals, the coal formation bedrock above coal mine has mined the mining area mainly was composed of two big kind of the sandstone and the mudstone .