In an Unweathered Sample of Detrital Sedimentary Rock,the Ratio of an Unstable

question 29

Multiple Choice

In an unweathered sample of detrital sedimentary rock,the ratio of an unstable isotope to its stable daughter isotope is 1/15.If no daughters were present at the time the rock cooled below closure temperature,and the half-life of the reaction is 50 million years,how old is the rock?

• A)200 million years
• B)400 million years
• C)750 million years
• D)None of the above are correct.

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