Formation and evolution mechanism of groundwater in Huibaoling iron mine area revealed by hydrochemistry and isotope

Objective In response to the insufficient research on groundwater in the Huibaoling iron mine, the focus is on studying the sources and formation mechanisms of groundwater in the mining area, in order to guide the prevention and control of mine water hazards.

Method Based on the hydrogeological characteristics of the Huibaoling iron mine, hydrochemistry and hydrogen oxygen isotopes were selected to reveal the sources, formation mechanisms, and hydraulic connections of various types of groundwater in its mining area.

Results The research shows that various groundwater recharge sources are atmospheric precipitation, which is significantly affected by leaching during the runoff process. The ions in the fracture water of the Liguan Formation and the Erqingshan Formation mainly come from the dissolution of carbonate, sulfate minerals, and salt rocks; The Na⁺ and K⁺ in the fissure water of Shancaoyu Formation come from the dissolution of silicate minerals, while Ca²⁺, Mg²⁺, HCO₃⁻, and SO₄²⁻ mainly come from the dissolution of carbonates, sulfates, and pyrite oxidation. Cation exchange leads to a relative surplus of K⁺ +Na⁺ and a relative deficit of Ca²⁺+Mg²⁺; The fissure water in the Liguan Formation is significantly affected by human activities, mainly manifested in the external input of NO₃⁻. The fissure water in the Erqingshan Formation and the Shancaoyu Formation are weakly affected by human activities.

Conclusion There are no strong water channels or hydraulic connections between each layer of groundwater. Different prevention and control measures have been proposed for different types of groundwater flooding in the mine.