Geochronological implications of ²¹⁰Pb and ¹³⁷Cs mobility in cave guano deposits

Authors

Donald A. McFarlane, The Claremont Colleges, California, USAFollow
Joyce Lundberg, Carleton University, Ottawa, CanadaFollow

Highlights

• ²¹⁰Pb and ¹³⁷CS dating techniques have been used to establish chronologies guano deposits
• Guano deposits may experience rapid decomposition resulting in low pH fluids in the guano
• ²¹⁰Pb and ¹³⁷CS are shown to be highly mobile under moist, low Ph conditions
• ²¹⁰Pb and ¹³⁷Cs chronologies should be supported by an independent, concordant ¹⁴C date series

Abstract

Some recent publications on the paleo- and historical environmental interpretation of bat guano sequences have relied on ²¹⁰Pb and ¹³⁷Cs distribution to establish age-depth models, even when these are at odds with radiocarbon models in the lower parts of the sequence. Here, we present both field and laboratory evidence for the unpredictable mobility of lead and cesium in decomposing bat guano deposits. We suggest that ²¹⁰Pb- and ¹³⁷Cs-based chronologies of bat guano deposits should only be used when independently supported, for example, by a robust radiocarbon age-depth model.

DOI

https://doi.org/10.5038/1827-806X.50.3.2391

Creative Commons License

This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 4.0 License.

Recommended Citation

McFarlane, D.A., Lundberg, J., 2021. Geochronological implications of ²¹⁰Pb and ¹³⁷Cs mobility in cave guano deposits. International Journal of Speleology, 50(3), 239-248. https://doi.org/10.5038/1827-806X.50.3.2391