Chemical weathering profile in the V–Ti–Fe mine tailings pond: a basalt-weathering analog

• 作者: OA Xiaolin Zhang Yinger Deng Liang Tang Zhengmeng Hou Jinsong Yang .College of Environment and Civil Engineering Chengdu University of Technology .Longchang Natural Resources and Planning Bureau .College of Earth Sciences Chengdu University of Technology .Institute of Subsurface Energy Systems Clausthal University of Technology .Key Laboratory of Quaternary Chronology and Hydro-Environmental Evolution Institute of Hydrogeology and Environmental Geology China Geological Survey
• 来源期刊: 地球化学学报(英文）
• 学科: 地球科学
• 年，卷（期）: 2025,（6）
• 页码范围: 75-90
• 页数: 16页
• 语种: 中文

摘要

The（ultra-）mafic mine tailings pond revealed a weathering discrepancy in the tailings profile, which provided a valuable analog to assess the role of carbonate and silicate weathering of the basalt. In this study, drill-cores samples were selected from the Wanniangou V–Ti–Fe mine tailings pond（Sichuan province, China） to investigate the mineralogicand geochemical characteristics in the tailings profile. The results reveal（1） the tailings pond profile consist of upper and lower layers. The upper layer is composed of carbonate weathering（1.4 %）, which was formed in the initial stages of tailings exposure and represented a minimal weathering degree.（2） The lower layer was primarily observed at the aquifer zone of the tailings pond, and was consistent with 0.45 % carbonate weathering and 48.4 % silicate weathering.（3） The weathering discrepancy in the tailings profile could be due to the sulfide oxidation and aerobic/flowing aquifer, which facilitate the water-tailings reactions. The tailings profile provides an analog to studying basalt weathering, as it spans both carbonate and silicate weathering. This research reinforces the idea that silicate weathering is predominant in basaltic areas and plays a crucial role in regulating atmospheric CO2（carbon dioxide） levels on Earth.