| Mine water disaster is one kind of the main geological hazard on the process of mine mining, including coalmine mining; meanwhile, it is an important factor which restricts the production activities of coalmine and its sustainable development. So it is important to discriminate the source of coalmine water-inrush. So this paper choose Xinzhuangzi coalfield of Huainan mining area as study area, adopt theoretical analyzing method and case study. On the basis of collecting and arranging the hydrological and hydrogeochemical data and combination with the water quality data of the past years, the sampling points are designed reasonably; meanwhile, the water quality is detected. Then analyze the general chemical characteristics and the isotopic and trace elemental characteristics of the main pouring water aquifers. The results get from the above study show as the following:(1) By contrast the water quality types and ionic distribution features of the main pouring water aquifers, characteristic ions are found, and the characteristic ionic model is built: if [Ca2+]<30mg/L&[Mg2+]<15mg/L&[Na++K+]>300mg/L, the water sample should be subject to the coal aquifer; or else, it belongs to other aquifers. In the Ordovician limestone aquifer, the MEQ percentage of chloride ion is higher than other aquifers'; it is almost above 35%. According to this, 65% correct rate for Ordovician limestone aquifer is met. The sulfite concentration of most goaf water samples is above 1500mg/L.(2) Choose typical exploration lineⅧ-Ⅸto analyze the chemical characteristics of Xinzhuangzi coalfield in vertical profile. Calcium concentration presents lessening trend as the sampling depth deeper, the change trend of sodium concentration is opposite.(3) Research the relationship between elements based on the sample examination of 51 trace elements. In the limestone aquifer, concentration of Ba is higher and U is lower than the water in other aquifer. One coal aquifer water sample has higher concentration of As, Se and Mo. And the Strontium concentration of goaf water is above 2150μg/L, it's higher than the water of any other aquifer. Statistical analysis of 13 typical trace elements was carried, the method are correlation analysis, cluster analysis and principal component analysis. Through principal component analysis three principal components are got, the first principal component has close relationship with the lixiviation of water-rock and the recharge of evaporative precipitation, the second appears the effluence of a direct recharge of surface water through fissure structures, and the third principal component relates to the recharge of surface water table which flows through the research area. The research on the stable isotope 18O and D shows that the main recharge source of groundwater is precipitation after evaporate, and precipitation recharges a few areas directly.(4) On the basis of the water chemical analysis on the main pouring water aquifers, six conventional ions and six conventional ion combining total hardness, temporary hardness and pH are chose as discriminant index respectively. Discriminant models, including grey correlation model and Bayesian model, are built in the research area; the results are obtained through comparing two models: judgment right rate of two models are over 70%, but the Bayesian model has higher correct rate when choose six conventional ion combining total hardness, temporary hardness and pH as discriminant index, it can discriminate the bursting source better in Xinzhuangzi coalfield, achieve rapid discriminate of underground water-bursting. The accuracy of model needs to improve further.
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