Study On The Hydrochemical Characteristics And Numerical Simulation Of Groundwater Of Jiulong Coal Mine

Handan is one of China's important coal-producing area, the mining depth is increasing with the continuous exploitation of deep coal resources. However, the coal seams of most coalfields deposit over a well-connected and water-rich Ordovician carbonate aquifer, these make the deep mining face much higher risk from Oedovician Limestone Groundwater(OLG) with the mining depth increasing. On the other hand, Fengfeng mining area in Handan is short of water resource, the evacuating and draining water for long time make the water shortage more and more severce. Therefore, study on the hydrogeochemistry and hydrodynamic field is quite important for the safety of deep coal mining and the protection of water resources.This paper takes Jiulong mine for example, firstly, Descriptive statics and piper diagram technology were used to study the hydrochemistry of groundwater, in order to determine the water bursting sources accurately and rapidly, discriminate models were built. Secondly, the ration of ions and saturation index were used to analyse the circulation and runoff condition of groundwater. Then, the groundwater flow modeling was employed to study the hydrogeological parameters of Ordovicaian limestone, it can provide suggestions for the coal mine safety and prevent the water-inrush. The main results are as follows:(1) Jiulong mine is a quite closeld block segment, the water types of sandstone water, Yeqing water, Daqing water and OLG is distinctly different from the adjacent mine.(2) The dominant water type of OLG is Cl-SO4-Ca-Na, the concentration of SO42-? Mg2+ and TDS in OLG is higher than the other, but the concentration of HCO3" is on the contrary; The Daqing water quality is similar with OLG and water types are Cl-SO4-Ca-Na and Cl-SO4-Na-Ca, they have some hydraulic connection according to pumping test.(3) By comparing the grey relational analysis and the Bayes' discriminant analysis, results show the latter is better, the latter is suggested using to distinguish the sources of mine water.(4) The main hydrogeochemical evolution of OLG are the dissolution of halite, the precipitation of calcite and dolomite, cation exchange, the gypsum is in a balanced state or slightly dissolved.(5) GMS was used to simulate the groundwater flow of pumping test and the reasonable hydrogeological parameters were obtained.