Discrimination Of Water-inrush Sources And Evolution Analysis Of Hydrogeochemical Characteristics Under The Effect Of Mining In Renlou Coal Mine

In order to reveal the temporal and spatial evolution of hydrogeochemical characteristics of the main water-inrush aquifers under the influence of mining.Taking Renlou Coal Mine in Huaibei coalfield as an example,this paper collects hydrogeochemical data of the fourth aquifer of the Cenozoic loose layer,the sandstone fissure aquifer of the top and floor of the Permian main coal seam,and the limestone karst aquifer of the Taiyuan Formation of the Carboniferous system.Through the analysis of the distribution characteristics of hydrogen and oxygen stable isotope composition in the study area,the source and mode of recharge of different aquifers are determined.At the same time,the principal component analysis method and the water source discrimination inversion analysis method in the multivariate statistical analysis are used to reveal the hydrogeochemical evolution characteristics of different aquifers under the influence of mining from the time and space dimensions.Hydrogen and oxygen stable isotope analysis shows that the Quaternary aquifer receives the direct infiltration and retention infiltration supplement of atmospheric precipitation,the Permian aquifer receives the retention infiltration supplement of atmospheric precipitation,and the Carboniferous aquifer receives the direct infiltration supplement of atmospheric precipitation.The results of principal component analysis show that the formation of water chemistry of different aquifers in the study area is mainly controlled by solution filtration dissolution,cation alternate adsorption and desulphate.Under the effect of coal mining,the dissolution and filtration of the Quaternary aquifer has been strengthened,the desulfurization of the Permian aquifer has been weakened,and the hydrochemical environment of the Carboniferous aquifer has changed little.According to the mechanism of water rock interaction revealed by principal component analysis and the spatial location of the misjudgment point in the discrimination model,the spatial evolution of the hydrochemical environment of the main water filled aquifers in Renlou Coal Mine is analyzed.The results show that the hydrochemical environment of the Quaternary aquifers is greatly affected by mining and has a certain hydraulic connection with the Carboniferous aquifers in the central region;the hydrochemical environment of the Permian system Generally speaking,the environment is not affected by mining,showing a relatively closed hydrogeological environment,but has a certain hydraulic connection with the Quaternary aquifer in some areas;the hydrochemical environment of the Carboniferous aquifer is controlled by typical faults and karst collapse columns,and has a certain hydraulic connection with the Quaternary aquifer and the Permian aquifer.The research results are of great significance to the safety production of coal mines and the protection of groundwater resources.