1. Local hydroclimate alters interpretation of speleothem δ 18O records
- Author
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E. W. Patterson, V. Skiba, A. Wolf, M. L. Griffiths, D. McGee, T. N. Bùi, M. X. Trần, T. H. Đinh, Q. Đỗ-Trọng, G. R. Goldsmith, V. Ersek, and K. R. Johnson
- Subjects
Science - Abstract
Abstract Oxygen isotopes (δ 18O) are the most commonly utilized speleothem proxy and have provided many foundational records of paleoclimate. Thus, understanding processes affecting speleothem δ 18O is crucial. Yet, prior calcite precipitation (PCP), a process driven by local hydrology, is a widely ignored control of speleothem δ 18O. Here we investigate the effects of PCP on a stalagmite δ 18O record from central Vietnam, spanning 45 – 4 ka. We employ a geochemical model that utilizes speleothem Mg/Ca and cave monitoring data to correct the δ 18O record for PCP effects. The resulting record exhibits improved agreement with regional speleothem δ 18O records and climate model simulations, suggesting that the corrected record more accurately reflects precipitation δ 18O (δ 18Op). Without considering PCP, our interpretations of the δ 18O record would have been misleading. To avoid misinterpretations of speleothem δ 18O, our results emphasize the necessity of considering PCP as a significant driver of speleothem δ 18O.
- Published
- 2024
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