基于TOUGHREACT的成矿过程化学反应数值模拟——以虎头崖铅锌多金属矿床为例

虎头崖铅锌多金属矿床是青海省祁漫塔格成矿带中典型的矽卡岩型矿床.本文基于前人对该矿区地质特征、矿物学和地球化学特征等方面的研究成果,利用TOUGHREACT数值模拟软件,针对石英-晚期硫化物成矿阶段进行成矿过程化学反应数值模拟研究.通过建立地质概念模型和网格化物化参数的设置,在设置的时间步长内对多相流体流动和热对流传导...

The TOUGHREACT-based numerical simulation of chemical reactions in ore-forming process: A case study of Hutouya Pb-Zn polymetallic deposit

The Hutouya Pb-Zn polymetallic deposit located in Qinghai,China,is a typical skarn-type deposit in the Qimantage mineralization belt.Combined with previous studies on the geological features,mineralogy and geochemical characteristics of the deposit we used the software of TOUGHREACT to simulate numerically the chemical reactions of quartz-late sulfide mineralization stage.Geological conceptual model was built,the physicochemical parameters set in the grids,thermal convection and conduction of the multiphase fluid,solute transportation,and geochemical reaction processes within a set time step simulated and calculated.The general trend of chemical equilibrium concentration of ore-forming elements under different temperature and pressure conditions and the influence on dissolution and precipitation of galena and sphalerite was studied.The results show that the chemical equilibrium concentration of Pb^2+decreased sharply when the temperature dropped from 250℃to 155℃,and the chemical equilibrium concentration of Zn^2+decreased sharply when the temperature dropped from 300℃to 100℃.Precipitation of minerals onsumes a large number of relevant ore-forming elements.The influence on chemical equilibrium concentration of ore-forming elements is different under different temperatutre and pressure.Temperature is the key factor controlling the chemical reaction of galena and sphalerite precipitation,and the influence of pressure is small.The simulation results are relatively consistent with the traditional geological interpretation results and prove the validity of the numerical simulation.