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Author Question: Why is the oldest continental crust (4.4 billion years) so much older than the oldest oceanic crust ... (Read 117 times)

Lobcity

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on: Jul 16, 2018
Why is the oldest continental crust (4.4 billion years) so much older than the oldest oceanic crust (180 million years)?
 
  What will be an ideal response?

Question 2

How can we estimate the abundances of chemical elements in the early solar system?
 
  What will be an ideal response?


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alvinum

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

All of the oceanic crust older than 180 million years has been destroyed by subduction.

Answer to Question 2

We can use the composition of meteorites that have not been modified by accretion into planetesimals.


Lobcity

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Reply 2 on: Jul 16, 2018
Excellent

aliotak

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Reply 3 on: Yesterday
Great answer, keep it coming :)

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