Zhang Jun-Ke, Chen Ke, Liu Zhong-Fa, Shao Yong-Jun, Tan Hua-Jie, Tan Rui-Chang, Zhang Tian-Dong, Zhang Jun-Ke, Chen Ke, Liu Zhong-Fa, Shao Yong-Jun, Tan Hua-Jie, Tan Rui-Chang, and Zhang Tian-Dong
In-situ LA-ICP-MS analysis and S isotopes of pyrite from the Baoshan Cu polymetallic deposit were conducted to investigate the ore-forming process and the enrichment mechanism of elements. Three generations of pyrite (Py I, Py II, and Py III) in the skarn-type ores and pyrite in the carbonate-hosted sulphide ores from central, western, and northern (C_Py, W_Py, and N_Py) mining districts are selected for comparison. Compared with Py I and Py III, the contents of most elements in Py II are apparently higher. The As and Se contents are high within a wide range and are decoupled in the growth band of the C_Py. The highest As, Se, and Pb contents were found in W_Py and N_Py. These results indicate the drastic changes in the temperature and fluid mixing during the mineralisation. The occurrence of fluctuation and change in temperature and f(O2) was triggered by intermittent pulses of magmatic-hydrothermal fluids, mixing with meteoric water, and water−rock interactions. The sulphur isotopes of all species of pyrite indicated the magmatic source. The change in the f(O2) conditions caused slight differences in the S isotope compositions. Consequently, a metallogenic model was proposed to explain the ore-forming processes., In-situ LA-ICP-MS analysis and S isotopes of pyrite from the Baoshan Cu polymetallic deposit were conducted to investigate the ore-forming process and the enrichment mechanism of elements. Three generations of pyrite (Py I, Py II, and Py III) in the skarn-type ores and pyrite in the carbonate-hosted sulphide ores from central, western, and northern (C_Py, W_Py, and N_Py) mining districts are selected for comparison. Compared with Py I and Py III, the contents of most elements in Py II are apparently higher. The As and Se contents are high within a wide range and are decoupled in the growth band of the C_Py. The highest As, Se, and Pb contents were found in W_Py and N_Py. These results indicate the drastic changes in the temperature and fluid mixing during the mineralisation. The occurrence of fluctuation and change in temperature and f(O2) was triggered by intermittent pulses of magmatic-hydrothermal fluids, mixing with meteoric water, and water−rock interactions. The sulphur isotopes of all species of pyrite indicated the magmatic source. The change in the f(O2) conditions caused slight differences in the S isotope compositions. Consequently, a metallogenic model was proposed to explain the ore-forming processes.