Water-richness evaluation of Luohe Formation aquifer above coal seam based on combination weighting method

Hetaoyu well field has large production capacity and stable distribution of coal seam， The thick sandstone aquifer of Luohe Formation in the roof of coal seam is the main water-filling aquifer which will result in coal seam roof water damage and threatening the safety of mine production with the deepening of mining degree when the water-conducting fissure zone leads to the water-rich area of the overlying aquife. It is necessary for the safety mining of coal mine to find out the law of water-rich distribution of aquifer, because water richness evaluation of coal seam roof aquifer is the basis of water hazard prevention and control. In order to evaluate the water richness of Luohe Formation aquifer in the first mining area of the Hetaoyu well field, six indexes including aquifer thickness, collecting rate of drill core, thickness ratio of brittle-plasticity, washing liquid consumption, permeability coefficient, unit water inflow were selected as evaluation factors by analyzing borehole data and other well fiel