Water and gas chemistry data from: Mariner, R.H., Evans, W.C., Presser, T.S. and White, L.D., 2003. Excess nitrogen in selected thermal and mineral springs of the Cascade Range in northern California, Oregon, and Washington: sedimentary or volcanic in origin?. Journal of volcanology and Geothermal Research, 121(1-2), pp.99-114. https://doi.org/10.1016/S0377-0273(02)00414-6. Water chemistry data was digitized for 21 samples. Reported attributes include: Sample name, Type, Reported latitude, Reported longitude, State, Latitude, Longitude, Location resolution, Location error, Source, Temperature, pH (field), Boron (B), Bromide (Br), Calcium (Ca), Chloride (Cl), Fluoride (F), Alkalinity as bicarbonate (HCO3), Potassium (K), Magnesium (Mg), Sodium (Na), Silica (SiO2), Sulfate (SO4), Cations, Anions, Reported total dissolved solids, Salinity, Charge balance, Digitizer comment. Gas chemistry data was digitized for 88 samples. Reported attributes include: Sample name, Type, Collection date, Reported latitude, Reported longitude, State, Latitude, Longitude, Location resolution, Location error, Source, Temperature, Total gas, Argon (Ar), Ethane (C2H6), Methane (CH4), Carbon dioxide (CO2), Hydrogen (H2), Hydrogen sulfide (H2S), Helium (He), Nitrogen (N2), Oxygen (O2), Dissolved argon (Ar dissolved), Dissolved methane (CH4 dissolved), Dissolved helium (He dissolved), Dissolved nitrogen (N2 dissolved), Dissolved oxygen (O2 dissolved), Isotopic ratio of helium (3He/4He), Isotopic composition of nitrogen (Delta 15N), Author comment, Digitizer comment. Data was digitized from Tables 1, 2, and 3. The following tables were not digitized: Table 4: estimated total dissolved gas concentration before free-gas formation.