Research On Mine Inflow Prediction At Depth Of The Wushan Copper Area In Ruichang, Jiangxi

Wushan copper mine in Ruichang,Jiangxi is a larger underground mine in our country,which is composed of the south and north part.The upper part of mine has been mined for many years,the deeper ore body will be the main target in the future mining.The research of deep hydrogeological conditions is a very important topic in the production after entering the deep mine.With the increase of mining depth,new changes in deep hydrogeological conditions that may occur.Therefore,the research on deep hydrogeological conditions and its changes,forecasting of water yield of the south and the north mining middle part,giving some data and technique foundation is necessary.On the basis of data collection,firstly we used GOCAD software to build a three-dimensional model of the geological structure of the study area.Secondly we extracted each elevation of rock formation and combined profiling.Knowing more information of the geological conditions and hydrogeological conditions,we established a hydrogeological conceptual model.After using the principles of equivalence permeability coefficient and negative exponential model,we combined structural model,then we using GMS established a groundwater flow model which stress period is February,2014-January,2015.When the model is fitting,we discussed the East and the West water blocking body and draw a conclusion that they have lost their water-resistance.We done a comparison about the strengths and weaknesses of the local sensibility analysis and global sensitivity analysis through the uncertainty analysis on groundwater flow numerical simulation model.It is find out that permeability coefficient is the main uncertain factor.Then we introduce the orthogonal test to sensitivity analysis,and obtained the combined effects of a representative of each of the partition coefficient of permeability of the model.This method not only to make up for the local sensitivity analysis can only be considered a single parameter on the result,but also greatly simplifies the global sensitivity analysis cumbersome.In the south part,the stable water yield of mine 360m deep below the surface is calculated to be 9706.01-10178.81m~3/d.1210m deep below the surface is calculated to be14129.45-17567.99 m~3/d.In the north part,the stable water yield of mine 360m deep below the surface is calculated to be 5025.43-5226.63m~3/d.1210m deep below the surface is calculated to be 6811.10-8028.78m~3/d.Under deep mining conditions in future,with the depth of exploitation increases,the water yield of the south part and the north part is increasing.But the growth rate will gradually slow down,finally reach a steady.In the north part,the growth rate from 5.86%slowed to 0.08%.In the South part,the growth rate from 7.91%slowed to0.48%.By the way of comparative analysis of groundwater flow field caused by different mining part,we can see the water gallery-centered drain with the deepening exploitation levels.The groundwater depression cone is expanding.One hand the groundwater table lowers greatly around the pit,forming a drawdown funnel to the west.On the other hand,the expanding of drawdown funnel to the Quaternary coverage area in the south and the east of Chi lake is slow and limited.As mining goes deeper,the groundwater table in the periphery of the mining area is falling away.However,the descent range is small and stable.