Hydrogeochemical Characteristics And Formation Mechanism Of Coal-bearing Sandstone Groundwater In Guxie Mines

The Guxie mining area is located in the southwestern part of the Panxie mining area in Huainan.The front edge of Huainan Nappe and the turning end of the folds are complex.The hydrogeological conditions are more complicated.There are many 11-2 and 13-1 coal seam roof and floor water inrush accidents.At the time,it has the characteristics of large initial water volume,fast decay,and high water pressure(temperature).It poses a serious threat to mining.Coal-series sandstone water is one of the main water-filled water sources in the mine.It is of theoretical and practical significance to carry out research on the characteristics of hydrogeochemical composition,spatial distribution and formation mechanism,and to identify targeted water inrush water sources from coal roof and floor,and to take targeted prevention measures.The thesis takes the sandstone water of 11-2 coal seam and 13-1 coal seam as the object.On the basis of consulting relevant domestic and foreign literatures and systematic analysis of hydrogeological conditions,by collecting and testing water samples,it adopts multivariate statistical analysis,Piper three-line diagram method,ion combination ratio Analysis and other methods have analyzed the spatial distribution characteristics of the water chemical components of sandstone water.On this basis,a combination of hydrogeochemical simulation method and principal component analysis method is used to reveal the formation of sandstone water and its mechanism.The results show that:1)In the area,Na++K+is the main cation in the water of 11-2 Coal Seam and 13-1 coal seam roof sandstone,HCO3·Cl-Na+K and Cl·HCO3-Na+K are the main hydrochemical types in the 11-2 Coal Seam roof,while Cl-Na+K,Cl·HCO3-Na+K and HCO3·Cl-Na+K are the main hydrochemical types in the 13-1 coal seam roof;2)In the vertical distribution,Na++K+has a negative correlation with Ca2+and Mg2+.Na++K+increases with the increase of depth at any time,while anions vary in different aquifers.On the plane,the ionic salinity in the sandstone water of the 11-2 coal seam roof gradually increases from the northwest to the southeast of the mining area,and the ionic salinity in the sandstone water of the 13-1 coal seam roof gradually increases from the northwest to the southeast3)Sandstone water of coal chemistry showed leaching effect cation exchange adsorption,sulfuric acid and de-oxidation effect.Among them,the 11-2 coal seam sandstone water in Xieqiao Mine is mainly desulfurized,and the 13-1 coal seam sandstone water in Xieqiao Mine is greatly affected by leaching and pyrite oxidation;Mainly based on pyrite oxidation and cation exchange adsorption,Gubei 11-2 coal seam sandstone water is mainly based on cation exchange adsorption,pyrite oxidation and leaching,Zhangji and Gubei 13-1 Coalbed sandstone water is dominated by leaching.Figure[44]table[9]reference[97]...