Ore-Forming Processes at the Xiajinbao Gold Deposit in Eastern Hebei Province: Constraints from EPMA and LA-ICPMS Analysis
Cheng Wang,
Yongjun Shao,
Kuanxin Huang,
Haodi Zhou,
Jianguo Zhang,
Zhongfa Liu,
Qingquan Liu
Affiliations
Cheng Wang
Key Laboratory of Metallogenic Prediction of Non-Ferrous Metals and Geological Environment Monitoring, Central South University, Ministry of Education, Changsha 410083, China
Yongjun Shao
Key Laboratory of Metallogenic Prediction of Non-Ferrous Metals and Geological Environment Monitoring, Central South University, Ministry of Education, Changsha 410083, China
Kuanxin Huang
Key Laboratory of Metallogenic Prediction of Non-Ferrous Metals and Geological Environment Monitoring, Central South University, Ministry of Education, Changsha 410083, China
Haodi Zhou
Hunan Key Laboratory of Land and Resources Evaluation and Utilization, Hunan Planning Institute of Land and Resources, Changsha 410007, China
Jianguo Zhang
Key Laboratory of Metallogenic Prediction of Non-Ferrous Metals and Geological Environment Monitoring, Central South University, Ministry of Education, Changsha 410083, China
Zhongfa Liu
Key Laboratory of Metallogenic Prediction of Non-Ferrous Metals and Geological Environment Monitoring, Central South University, Ministry of Education, Changsha 410083, China
Qingquan Liu
School of Resources and Safety Engineering, Central South University, Changsha 410083, China
The Xiajinbao gold deposit is located at the northern margin of the North China Craton. Hydrothermal pyrites belonging to three stages were identified: Py1; Py2; and Py3. Geochemical study of these pyrites was conducted using electron probe microanalysis and laser ablation inductively coupled plasma mass spectrometry to investigate the distributions of minor and trace elements, constrain pyrite genesis, and to obtain an improved understanding of the ore-forming processes. Py1 and Py2 contain high concentrations of Au and are interpreted to have been deposited from fluids from a dominantly magmatic source. Py3 grains have the lowest Co/Ni ratios. All generations of pyrite were deposited by mixing of meteoric waters with magmatic-hydrothermal fluids. Boiling of early ore-forming fluids led to the precipitation of Py1 and gold. Decreasing fO2 in the ore-forming system resulted in the formation of Py2 and gold. Fluid mixing was the dominant controlling factor for the precipitation of Py3 together with small amounts of gold.
