Why Is the Major Branch of the K-40 Decay to Ca-40

question 143

Multiple Choice

Why is the major branch of the K-40 decay to Ca-40 not useful in most cases for whole rock dating?

• A)It only works 89% of the time.
• B)The Ca-40 that is produced by decay is indistinguishable from the naturally most abundant isotope of Ca that may have been present initially.
• C)The decay to Ar-40 is faster and has wider geologic applicability.
• D)Ca-40 is itself unstable and further decays to more daughter products.

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