HyGCS: Hydro-Geochemical Classification Suite

HyGCS is a Python toolkit for hysteresis analysis and geochemical phase classification in concentration-discharge (C-Q) relationships. It builds on and combines a series of published C-Q analysis procedures and seeks to make them available in a comprehensive manner. HyGCS provides tools for analyzing water quality dynamics in catchments, mine drainage systems, and environmental monitoring networks. The package integrates scientifically validated methods for: Multi-method hysteresis analysis (HARP, Zuecco, Lloyd/Lawler) CVc/CVq variability analysis (Musolff et al., 2015) C-Q slope calculation (power-law exponents) Geochemical phase classification (6-phase hierarchical system) Comprehensive visualization tools Please note, that despite all testing and care, this code is scientific and experimental. Do not trust the results before throughout analysis. The code has a couple of more or less hard-coded assumptions (like usual time series in days and spline interpolations) which might completely screw up under untested circumstances. Feel free to fork, contribute, extend with cc-by. The development of this code has been interactively supported with AI. Claude Code Sonnet 4.5 has been deployed to integrate and organize the code base.