Natural Thorium

["Elizabeth Algutifan"<elizabeth_algutifan@wssrap-host.wssrap.com>]

This is a question of semantics: What does the term "natural thorium" really
mean? A geologist colleague of mine came up to me this morning and asked me to
tell him the specific activity of natural thorium. As I got to thinking about
it, it occurred to me that if natural thorium is only referring to the thorium
isotopes in the decay chain, I can calculate it based on assuming secular
equilibrium between Th-232 and Th-228 (and say they both contribute half to the
total nat Th activity). Is that an oversimplification? 

Elizabeth Algutifan
Elizabeth_Algutifan@wssrap-host.wssrap.com

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