Luminescent microbanding in speleothems: High-resolution chronology and paleoclimate
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Publication Date
May 1994
Abstract
When illuminated by ultraviolet light, many calcite speleothems (stalagmites, stalactites, flowstones) display luminescence caused by the presence of organic (humic) substances occluded in the calcite. The amplitude of luminescence varies in a banded pattern parallel to growth layering. Through 14C and thermal ionization mass spectrometry uranium-series dating, we show that cyclical oscillations in the luminescence have periodicities ranging from a few days to ≥105 yr. A well-defined annual cycle is present in many vadose-zone speleothems and can be used to define the chronology of short-term events. This cycle is probably a response to hydrological events in the recharge to the cave. Longer term oscillations are inferred to be controlled by climate, through its effect on organic activity in the overlying soil.
Keywords
Absolute Age, Banded Materials, C-14, Calcite, Carbon, Carbonates, Cenozoic, Cycles, Dates, Experimental Studies, Geochronology, High-Resolution Methods, Holocene, Humates, Isotopes, Luminescence, Mass Spectra, Organic Compounds, Organic Materials, Paleoclimatology, Paleohydrology, Periodicity, Quaternary, Radi Active Isotopes, Solution Features, Spectra, Speleothems, Uranium Disequilibrium
Document Type
Article
Notes
Geology, Vol. 22, no. 5 (1994-05-01).
Identifier
SFS0072209_00001
Recommended Citation
Shopov, Y. Y.; Ford, D. C.; and Schwarrcz, H. P., "Luminescent microbanding in speleothems: High-resolution chronology and paleoclimate" (1994). KIP Articles. 3305.
https://digitalcommons.usf.edu/kip_articles/3305
