Fig. 2: Groundwater geochemistry and age dating. | Nature Communications

Fig. 2: Groundwater geochemistry and age dating.

From: Hydrogen and dark oxygen drive microbial productivity in diverse groundwater ecosystems

Fig. 2: Groundwater geochemistry and age dating.The alternative text for this image may have been generated using AI.

a Piper diagram of hydrochemical facies of each groundwater sample (circles) visualizing calcium/sodium mass ratio used as a proxy for geochemical evolution, i.e., residence time/age. Na: sodium, K: potassium, Ca: calcium, Mg: magnesium, Cl−: chloride, SO42−: sulfate, CO32−: carbonate, HCO3−: bicarbonate b Ca/Na ratio decreases with increasing residence time (14CDIC uncorrected age, BP: before present). 14C: 14carbon, DIC: dissolved inorganic carbon. Samples that accumulate in the plot around 40k yrs BP (detection limit of method) may be much older. 3H-positive samples (circles with crosses) comprise meteoric water past 1952 (H-bomb) and corroborate the age trend. c Schematic timeline and summary of water aging.

Back to article page