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Updated: Jul 11, 2026
11:19
Measuring Carbon-based Contaminant Mineralization Using Combined CO2 Flux and Radiocarbon Analyses
Published on: October 21, 2016
500,000-year stable carbon isotopic record from devils hole, nevada.
Science (New York, N.Y.)
|January 21, 1994
Summary
Carbon-13 variations in Devils Hole calcite reveal past climate shifts. These carbon isotope records correlate with glacial terminations, suggesting changes in atmospheric carbon dioxide and vegetation density.
Area of Science:
- Paleoclimatology
- Geochemistry
- Isotope Hydrology
Background:
- The Devils Hole calcite core (DH-11) provides a valuable archive of past environmental conditions.
- Understanding past climate variability is crucial for predicting future climate change.
Purpose of the Study:
- To analyze carbon-13 (delta(13)C) variations in the DH-11 calcite core.
- To investigate the relationship between delta(13)C and oxygen isotope ratios in the core.
- To interpret the paleoenvironmental implications of observed delta(13)C fluctuations.
Main Methods:
- Analysis of carbon-13 (delta(13)C) in vein calcite from the DH-11 core.
- Comparison of delta(13)C time series with oxygen isotope data.
- Modeling potential sources of delta(13)C variations.
Main Results:
- Four prominent delta(13)C minima were identified near glacial terminations V to II.
- The delta(13)C time series is inversely correlated with the oxygen isotope record, leading it by up to 7000 years.
- These variations likely reflect changes in the delta(13)C of aquifer recharge water.
Conclusions:
- The delta(13)C record may indicate global atmospheric CO(2) changes or regional vegetation shifts in the southern Great Basin.
- Minima in the delta(13)C record correspond to periods of maximum vegetation extent and density.
- The transport mechanism of these isotopic signals to Devils Hole without significant alteration remains an open question.
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