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Periodic Table--Osmium

Osmium has seven naturally-occurring isotopes, all of which are stable: 184Os, 186Os, 187Os, 188Os, 189Os, 190Os, and (most abundant) 192Os. 187Os is the daughter of rhenium-187 (half-life 4.56 x 1010 years: Luck and Allègre, 1983) and is most often measured in a 187Os/186Os ratio. This ratio, as well as the 187Re/187Os ratio, have been used extensively in dating terrestrial as well as meteoric rocks. However, the most notable application of Os in dating has been in conjunction with iridium, to analyze the layer of shocked quartz along the K-T boundary (Luck and Turekian, 1983).

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

Bowen, R. (1988). Isotopes in the Earth Sciences. Elsevier Applied Science, New York, 647 p.
Faure, G. (1986)."The Re-Os method of dating", in Principles of Isotope Geology, Second Edition. John Wiley and Sons, New York, pp. 264-274.
Luck, J.M., and Allègre, G.J. (1983). "187Re-187Os systematics in meteorites and cosmological consequences." Nature, 302: 130-132.
Luck, J.M., and Turekian, K.K. (1983). "Osmium-187/Osmium-186 in manganese nodules and the Cretaceous-Tertiary boundary." Science, 222: 613-615.
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Periodic Table
Fundamentals of Stable Isotope Geochemistry
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Isotope Publications
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