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Carbonates and Evaporites

, Volume 15, Issue 1, pp 1–6 | Cite as

U/Th isotopic study of speleothems from the Wadi Sannur Cavern, Eastern Desert of Egypt

  • Adel A. Dabous
  • J. K. Osmond
Article

Abstract

The Wadi Sannur Cavern was discovered in 1991 beneath an “Egyptian alabaster” (travertine) quarry, active since pharaonic times. It is the only extensively speleothem-decorated cavern that has been described in Egypt. Nine small stalagmites, 5–10 cm in diameter, were sectioned and sampled according to coloration bands a few cm thick. Of 32 individual samples several exhibited230Th/234U activity ratios greater than unity, indicative of open-system leaching of uranium, and several others had anomalous234U/238U activity ratios. The modal apparent age of the 17 “dateable” samples is close to 200,000 years, but because of leaching indications must be considered only a maximum age for the time of deposition of secondary carbonates in the cave. Both the initial formation of speleothems and subsequent leaching are consistent with what is known about pluvial climates in the Eastern Desert of Egypt.

Keywords

Uranium Egypt Thorium 234U Activity Ratio 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer 2000

Authors and Affiliations

  • Adel A. Dabous
    • 1
  • J. K. Osmond
    • 1
  1. 1.Department of Geological SciencesFlorida State UniversityTallahassee

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