Yifan Zeng , Qiang Wu , Aoshuang Mei , Lu Wang , Wenbin Yin , Lei Yang , Di Zhao , Shihao Meng , Hongfei Gao
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引用次数: 0
Abstract
The Jurassic coalfield in the mining area of western China exhibits a multi-layered groundwater system. However, it is subject to an arid and semi-arid climate with limited water resources. Consequently, the ecological environment is highly vulnerable, and the chemistry and quality of groundwater may be influenced by multiple factors. This study systematically the coal mining-motivated effect on the hydrochemistry and water quality of the groundwater system, using the Caojiatan Coal Mine as a case study. The analysis incorporates a combination of the self-organizing maps (SOM), entropy-weighted water quality index (EWQI), and traditional hydrochemical analysis methods. After coal mining, there was an increase in the proportion of HCO3-Ca and HCO3-Mg in the groundwater samples of J2z, J2y4, and J2y5. The groundwater is controlled by cation exchange as a whole. The J2y4 and above groundwater is influenced by both the dissolution of carbonate and silicate rocks before coal mining. After coal mining, the Quaternary and J2a groundwater in the western wing is primarily influenced by the dissolution of carbonate rocks; the J2z, J2y4 and J2y5 groundwater is primarily governed by the dissolution of silicate rocks and the oxidation of FeS2; the J2y3 and below groundwater is primarily controlled by the dissolution of evaporate rocks. The resulting dilution effect after coal mining and the implementation of measures for the discharge of treated mine water make the groundwater quality of the J2y4 and higher aquifers tend to be better. The research findings serve as a valuable reference for promoting the sustainable development and protection of groundwater resources not only in the study area but also in other coal mines.
期刊介绍:
Journal of Geochemical Exploration is mostly dedicated to publication of original studies in exploration and environmental geochemistry and related topics.
Contributions considered of prevalent interest for the journal include researches based on the application of innovative methods to:
define the genesis and the evolution of mineral deposits including transfer of elements in large-scale mineralized areas.
analyze complex systems at the boundaries between bio-geochemistry, metal transport and mineral accumulation.
evaluate effects of historical mining activities on the surface environment.
trace pollutant sources and define their fate and transport models in the near-surface and surface environments involving solid, fluid and aerial matrices.
assess and quantify natural and technogenic radioactivity in the environment.
determine geochemical anomalies and set baseline reference values using compositional data analysis, multivariate statistics and geo-spatial analysis.
assess the impacts of anthropogenic contamination on ecosystems and human health at local and regional scale to prioritize and classify risks through deterministic and stochastic approaches.
Papers dedicated to the presentation of newly developed methods in analytical geochemistry to be applied in the field or in laboratory are also within the topics of interest for the journal.