Hydrochemical Characteristics and Formation Mechanism of Quaternary Groundwater in Baoshan Basin, Western Yunnan, China

The shallow groundwater of the quaternary system in Baoshan basin, Yunnan Province is seriously polluted, threatening human health and restricting local socio-economic development; therefore, it necessary to investigate hydrochemical characteristics formation mechanisms basin. This study used EVS 2022 establish a 3D visual geological model basin divided aquifers into three systems, sampling 22, 9, 4 groups each system, respectively. Mathematical statistics, Piper’s trilinear diagram, Gibbs plots, Gaillardet model, ion ratio method, saturation, PCA-APCS-MLR were analyze genesis area. results show following: (1) types chemicals are mainly HCO3-Ca-Mg type HCO3-Ca, causes water chemical influenced by water–rock interaction alternate cation adsorption, rock with which exchanges substances carbonate rocks silicate rocks. (2) Fe2+, Mn2+, NH3-N contents systems I II exceed standard, activity area, pollution affected activities. (3) Four main categories factors obtained according namely dissolution filtration, migration enrichment factors, environmental factors; cumulative contribution variance was 77.84%, jointly hydrogeological conditions this provide basis for protection management where key area should be strengthened control.