500,000-year stable carbon isotopic record from Devils Hole, Nevada

T.B. Coplen; I.J. Winograd; J.M. Landwehr; A.C. Riggs

doi:10.1126/science.263.5145.361

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500,000-year stable carbon isotopic record from Devils Hole, Nevada

T.B. Coplen·I.J. Winograd·J.M. Landwehr·A.C. Riggs

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Abstract

The record of carbon-13 (δ 13 C) 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 δ 13 C time series is inversely correlated with the DH-11 oxygen isotope ratio time series and leads it by as much as 7000 years. The δ 13 C variations likely record fluctuations in the δ 13 C 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 δ 13 C of atmospheric CO 2 and, hence, the δ 13 C of continental biomass or (ii) variations in extent and density of vegetation in the southern Great Basin. In the latter case, δ 13 C minima at 414, 334, 246, and 133 thousand years ago mark times of maximum vegetation.

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Source-reported bounding extent: 36.379062987140315° to 36.48038829888887° latitude; -116.36559814113079° to -116.24409639159839° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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T.B. Coplen, I.J. Winograd, J.M. Landwehr, A.C. Riggs. 1994. 500,000-year stable carbon isotopic record from Devils Hole, Nevada. https://doi.org/10.1126/science.263.5145.361

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