Supplementary Tables for article " Influence of saline springs on river water chemistry: a K isotope perspective"

This dataset supports the hydrogeochemical investigation of river water and saline springs in the Jinggu catchment, Southwest China. The data provide comprehensive geochemical and isotopic measurements used to trace solute sources, quantify water-rock interaction, and model the impact of saline inputs on riverine potassium isotope signatures.

The dataset includes four structured tables:

Table S1: Sampling locations, major ion concentrations, and potassium isotope compositions
Contains field sampling details, concentrations of major ions (e.g., Na⁺, K⁺, Ca²⁺, Mg²⁺, Cl⁻, SO₄²⁻, HCO₃⁻), and measured potassium isotope compositions (δ⁴¹K) for all river water and saline spring samples. This table serves as the foundational geochemical dataset for the study.

Table S2: Hydrogen and oxygen isotope compositions (δ²H and δ¹⁸O) of selected samples
Reports stable water isotope data for a subset of river water and saline spring samples. These data are used to identify water origins, evaporation effects, and mixing processes within the catchment.

Table S3: Measured and atmosphere-corrected potassium isotope compositions (δ⁴¹K)
Provides both raw and atmosphere-corrected δ⁴¹K values for all samples, enabling accurate interpretation of potassium cycling and silicate weathering by removing atmospheric deposition influences.

Table S4: Modeled shifts in riverine δ⁴¹K values as a function of saline spring input fractions
Presents quantitative model outputs illustrating how riverine δ⁴¹K values respond to varying proportions of saline spring contribution. This table directly supports the interpretation of potassium isotope variability and saline water mixing in the catchment.

Scientific Relevance:
Collectively, these tables offer a systematic geochemical and isotopic framework for studying solute origin, weathering intensity, and fluid mixing in a catchment influenced by saline groundwater discharge. The dataset is valuable for researchers in hydrogeochemistry, isotope hydrology, low-temperature geochemistry, and environmental modeling.