Hydrogeochemical Characteristics of Spatiotemporal Variation, Controlling Factors and Travertine Deposition Capacity of the Springs and the Secondary Conversion Springs in Huanglong, a World Natural Heritage, Sichuan, China

To investigate the hydrochemical properties, influencing factors, and travertine deposition potential of the Springs and the Secondary Conversion Springs in the Huanglong Scenic Area, 14 surface water samples were gathered from two aquifers. The composition and controlling factors of hydrochemical elements in the region’s surface water were analysed using statistical methods, Pearson correlation, Piper diagrams, Gibbs diagrams, ion ratio analysis, and principal component analysis. The findings are as follows: (1) The dominant hydrochemical classification in the region is \({\text{HCO}}_{3}^{ - }\)–Ca²⁺. (2) The Springs exhibit significant spatial variability in hydrochemical traits, heavily influenced by factors such as temperature, aquifer materials, and terrain. In contrast, the Secondary Conversion Springs are less impacted by these variables. (3) The hydrochemical composition of the Springs and the Secondary Conversion Springs in July and September remained stable over time, primarily influenced by a single factor—water−rock interaction. The hydrochemical profile was mainly governed by the dissolution of carbonate rocks, with minor contributions from halite and gypsum dissolution. (4) The Springs in the study area are characterised by high \({{P}_{{{\text{C}}{{{\text{O}}}_{{\text{2}}}}}}}\), high \({\text{HCO}}_{3}^{ - }\) and high Ca²⁺, concentrations, providing the main sources of calcium and carbon for travertine deposition in the Secondary Conversion Springs, and the deposition capacity of travertine is mainly affected by Ca²⁺, \({\text{HCO}}_{3}^{ - }\), \({{P}_{{{\text{C}}{{{\text{O}}}_{{\text{2}}}}}}}\) and pH.