Multiple Choice
Which of the following is true of the magma formed from subducted ocean floor material that is eventually incorporated into continental crust?
A) the composition of the magma changes from a high silica content to a lower silica content by the incorporation of sediments and other materials when it melts.
B) the magma that forms in this way tends to produce more violent volcanic eruptions than magma derived directly from the aesthenosphere.
C) batholiths may create magma as they move downward into the subduction zone.
D) it has a low viscosity and rises easily to spread over the surface of the continental crust.
E) because this magma is exactly like the magma at sea-floor spreading centres,it creates new oceanic crust at the surface.
Correct Answer:

Verified
Correct Answer:
Verified
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