Question

Why is it generally more difficult to find very old rocks on the Earth than it is to find
them on the moon?

Answer 1

Wind; which is absent on the moon 
Water flow/rain; which is absent on the moon 
Plate Tectonics; which is absent on the moon 
Substantial Volcanic activity; which is absent on the moon 
Life/ Macro- and Micro- ; which is absent on the moon 
Glaciers; which are absent on the moon

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