Groundwater source identification incarbonate-hosted deposit using hydrogeochemistry, hydrogen and oxygen isotope method

The Maoping lead-zinc deposit in Yunnan is a complicated one with abundant gush-out groundwater filled through karst fissures. There is an urgent need to delineate the recharge sources and groundwater flow paths in order to carry out the design and optimization of groundwater prevention and control projects. This study systematically discusses the water filling sources and runoff passages based on hydrogeochemical and stable isotope methods, and simultaneously builds the hydrogeological conceptual model. The carboniferous karst aquifer is characterized by low temperature, low TDS, high NO-3, and enrichment in heavy isotopes. Nevertheless, the Devonian karst aquifer shows an increasing tendency of temperature, TDS and trace elements from north to south, coupling with the decreasing of NO-3 and extremely depleted light isotopes. All the above indexes directly and coincidently indicate the recharge sources and groundwater flow paths. The Carboniferous karst aquifer is recharged in the eastern karst depressions (the Xianji village), and flows to the mining area westward. Shallow groundwater in the northern part of the Devonian karst aquifer is supplied by the Carboniferous karst aquifer through faults dislocating the aquiclude, then mixes with the deep groundwater from the southern part, and finally feeds together towards the mine depression cone located in the central part.