Identification model of water inrush source based on statistical analysis in Fengyu minefield, Northwest China

Abstract

Rapid and effective identification of water inrush source is an important guarantee for mine safety production. Hydrogeochemical theory has been applied in coal mining and water prevention and control, but its application scale and coverage are limited. The main reason is that the existing research is mostly based on conventional hydrochemical indicators, and less applied in trace elements and environmental isotopes. In order to explore the evolution mechanism of water inrush in well field and realize the accurate identification of water inrush source, this paper takes Fengyu well field in Shuozhou City, Shanxi Province, China, as the research object. Based on the test results of conventional hydrochemistry, trace elements, and environmental isotope indexes of each aquifer, the hydrogeochemical distribution and evolution law of each aquifer in a minefield are analyzed. Combined with cluster analysis, principal component analysis, and Bayesian stepwise linear discriminant method, the discrimination model of mine water inrush source is established. The results show that, with the gradual increase of aquifer depth, the total dissolved solids (TDS) of water samples showed a decreasing trend; HCO3− is dominant in all aquifers, which may be the result of mixing after water inrush in each aquifer; the content of trace elements in underground aquifer of minefield can be summarized as three principal components of groundwater overflow, river recharge, and dissolution. The distribution of Shanxi water, Taiyuan water, and Ordovician water conforms to the height effect and temperature effect; the established discrimination model of water inrush source in minefield can effectively discriminate water inrush source. The calculation process is simple and the model structure is stable, which is worthy of promotion and application. The research results can provide a scientific basis for the development of water control measures (draining, depressurization, and plugging) in minefields.