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Periodic Table--Cesium

Cesium has only one naturally occurring stable isotope, 133Cs. The radiogenic isotope 137Cs has been used in hydrologic studies, analogous to the use of 3H. 137Cs is produced from detonation of nuclear weapons and emissions from nuclear power plants. Beginning in 1954 with the commencement of nuclear testing, 137Cs was released into the atmosphere where it is absorbed readily into solution. Once 137Cs enters the ground water, it is deposited on soil surfaces and removed from the landscape primarily by particle transport. As a result, the input function of these isotopes can be estimated as a function of time. The resulting activities of 137Cs in sediments can thus be used to understand the geomorphic history of catchments by dating cores and estimating rates of sediment deposition and thus catchment erosion.

134Cs has also been used in hydrology as a measure of cesium output by the nuclear power industry. This isotope is used because, while it is less prevalent than either 133Cs or 137Cs, 134Cs can be produced solely by nuclear reactions. 135Cs has also been used in this function.

134Cs and 135Cs, while less prevalent than either 133Cs or 137Cs, have also been used in hydrology as a measure of cesium output by the nuclear power industry, as they too are produced solely by anthropogenic sources.

Source of text: This review was assembled by Eric Caldwell and Dan Snyder from the references below.

Bierman, P.R., Albrecht, A., Bothner, M., Brown, E.T., Bullen, T., Gray, L.B. and Trupin, L. (1998). "Erosion, Weathering and Sedimentation." In: C. Kendall and J.J. McDonnell (Eds.), Isotope Tracers in Catchment Hydrology. Elsevier, Amsterdam, pp. 647-678.
Brauer, F. P., and Ballou, N. E. (1975). "Isotopic ratios of iodine and other radionuclides as nuclear power pollution indicators", In: Isotope Ratios as Pollutant Source and Behaviour Indicators, International Atomic Energy Agency, Vienna.
Krishnaswami, S., Lal, D., Martin, J.M. and Meybeck, M. (1971). "Geochronology of lake sediments." Earth and Planet. Sci. Lett., 11: 407-414.
Ritchie, J.C., Spraberry, J.A. and McHenry, J.R. (1974). "Estimating soil erosion from the redistribution of fallout 137Cs." Soil Sci. Am. Proc., 38: 137-139.
Schell, W. R., and Nevissi, A. (1983). "Sedimentation in lakes and reservoirs", in Guidebook on Nuclear Techniques in Hydrology, 1983 Edition, International Atomic Energy Agency, Vienna. pp. 163-176.
Walling, D. E., He, Q., and Quine, T. A. (1995) "Use of caesium-137 and lead-210 as tracers in soil erosion investigations." In: Ch. Leibundgut (Ed.), Tracer Technologies for Hydrological Systems, Galliard, Great Yarmouth. pp.163-172.
Related Links
Periodic Table
Fundamentals of Stable Isotope Geochemistry
General References
Isotope Publications
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