Ju P.-J.,Central South University |
Lai J.-Q.,Central South University |
Yang H.-J.,Liyuan Gold Deposit Ltd Liability Company |
Wang Y.-J.,Liyuan Gold Deposit Ltd Liability Company |
And 5 more authors.
Zhongguo Youse Jinshu Xuebao/Chinese Journal of Nonferrous Metals | Year: 2015
Liyuan Gold Deposit is located at the Taihang Mountain tectonic-magma-polymetallic metallogenic belt. Ore bodies mainly occur in the NNE-trending structural zone. The hydrothermal process can be divided into four stages, namely, A stage (quartz vein stage), B stage (quartz-pyrite stage), C stage (quartz-polymetallic sulfide stage) and D stage (quartz-carbonate stage). Three types of fluid inclusions are developed in B, C and D stages: aqueous inclusion (type I), CO2-aqueous inclusion (type II) and pure CO2 inclusion (type III). All three types of inclusions, mainly type I inclusions present in stage B, with homogenization temperatures ranging in 230-350 ℃, and salinities ranging from 1.82% to 12.63%. In addition to development of type I inclusions, type II and III inclusions increase significantly in stage C, with homogenization temperatures ranging from 200 ℃ to 330 ℃, salinities ranging in 1.82%-9.71%. Type I inclusions relatively develop in stage D, with homogenization temperatures concentrating in 140-170 ℃, and salinities ranging from 1.16% to 9.58%. High density of CO2 and CH4, H2 and N2 are found as gas compositions in the inclusions. Liquid phase of fluid is mainly composed of Ca2+, Na+, K+, SO4 2-, Cl-, F-. The calculated metallogenic pressures are in the range of 68-114 MPa, corresponding to capture temperature of 200-430 ℃, and the maximum estimated mineralization depth is 4.3 km. To sum up, the mineralization fluid of Liyuan Gold Deposit may be late magmatic hydrothermal fluid, belongs to low salinity, medium-low temperature, CO2-rich Ca2+(Na+, K+)-SO4 2-(Cl-, F-)-H2O-CO2 system. Liyuan Gold Deposit formed in intracontinental orogeny belongs to magmatic hydrothermal altered rock type gold deposit controlled by fracture zone. ©, 2015, Central South University of Technology. All right reserved.