Evolution And Recognition Of Groundwater Based On3D Geological Structure Model In Sunan Mining Area

The drilling and hydro-geological section data were collected, what combinedwith the chemistry test of major ions, trace elements and isotope in samples to surveygroundwater in Sunan mining area.3D hydro-geological structure model wasestablished using the GMS, what as a basis to study the groundwater runoffcharacteristics and the variation of quantity and water level. The hydrochemistrycharacters of major ions, trace elements and isotope were studied, the age ofgroundwater, as well as groundwater evolution in space and time were discussed. Inaddition, hydro-geochemical simulations were also completed by NetpathXL, and therelation between macro components and micro components were coupled to constructthe source identification model of groundwater. The main research results are asfollows:(1) The depth, thickness and distribution of aquifers and aquiclude werecorrectly recognized, for3D structure model of groundwater have better response tothe geological structure. The fourth aquifer in Quaternary (QA) is flow from south tonorth, and west to east, sandstone aquifer (SA) is mainly constituted by static reserves,with lateral runoff weakly, otherwise limestone aquifer (LA) in Taiyuan formation isflow from periphery to the center. Groundwater level in mining area decreasedobviously with the coal mining. Hydro-geochemistry process of QA is dominated bydissolution of feldspar with the CO2participation, the runoff and recharge of SA islimited, and LA is along with dissolution of calcite and dolomite in the runoff.(2) Groundwater from Sunan mining area were composed by sub-modern water,and the hydro-chemical characters of TDS, Ca2++Mg2+,D and18O showed that QA isflow from north to south, otherwise the LA in opposite. QA, SA and LA are mainlyaffected by the carbonation, sulfating and dissolution of carbonate in thehydro-geochemical process. In addition, the cation exchange adsorption reaction isobviously in SA and LA. Evolution processes of groundwater were influenced bygeological structure and human engineering activities, with the regularly change aboutgeochemical characteristics and ion concentrations in space and time.(3) Three aquifers groundwater have different chemical processes in mining area,with diverse influence factors. All groundwaters in three aquifers are not suit for drinkdirectly with high TDS concentrations, however, the suitability of irrigation weregenerally better, the quality of SA groundwater was worst. The major ions, trace elements and isotopic (D,18O,13Cdic,18Odicand87Sr/86Sr) have different characteristicsin diverse aquifers. Sr and Zr could be used as symbol trace element for LA and SA,with the good correlation with other elements or parameter. Source identificationgraphic of groundwater were established according to the diverse symbol ions, andsource identification model of groundwater were also completed by the statisticsanalysis based on hydrochemical parameter in Qidong coal mine and trace elementparameters in Sunan mining area. The application of rare earth elements and isotopesin source identification is enriched. The paper enriched the research about seepagefield and chemical field, macro components and micro components in mininggroundwater, which have guiding significance for the groundwater exploitation andsource identification in mining area.