500,000-Year Stable Carbon Isotopic Record from Devils Hole, Nevada

Abstract
The record of carbon-13 (δ13C) variations in DH-11 vein calcite core from Devils Hole, Nevada, shows four prominent minima near glacial terminations (glacial-interglacial transitions) V to II. The δ13C time series is inversely correlated with the DH-11 oxygen isotope ratio time series and leads it by as much as 7000 years. The δ13C variations likely record fluctuations in the δ13C of dissolved inorganic carbon of water recharging the aquifer. How such variations are transported 80 kilometers to Devils Hole without obliteration by water-rock reaction remains an enigma. The record may reflect (i) global variations in the δ13C of atmospheric CO2 and, hence, the δ13C of continental biomass or (ii) variations in extent and density of vegetation in the southern Great Basin. In the latter case, δ13C minima at 414, 334, 246, and 133 thousand years ago mark times of maximum vegetation.