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Author Question: What evidence tells us that early Earth contained radioactive isotopes that are no longer present? ... (Read 15 times)

crobinson2013

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on: Jul 16, 2018
What evidence tells us that early Earth contained radioactive isotopes that are no longer present?
 
  What will be an ideal response?

Question 2

Has the innermost part of Earth's core always been solid and constant in size?
 
  What will be an ideal response?


srodz

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Reply #1 on: Jul 16, 2018
Answer to Question 1

The daughter products of these isotopes are present in Earth rocks. They are also present in Moon rocks and in meteorites.

Answer to Question 2

No, the Earth's entire core was once molten. The core started to crystallize from the inside outward and continues to crystallize today. The inner core is slowly enlarging.


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