Compared with the mantle beneath a mid-ocean ridge,the mantle above a subduction zone
A)contains less water and melts at a lower temperature.
B)contains less water and melts at a higher temperature.
C)contains more water and melts at a lower temperature.
D)contains more water and melts at a higher temperature.

Question

Quizplus · Accepted Answer

The mantle above a subduction zone contains more water because the descending oceanic crust carries water into the mantle. This water lowers the melting point of the mantle rock, causing it to melt at a lower temperature compared to the drier mantle beneath a mid-ocean ridge.

Compared with the Mantle Beneath a Mid-Ocean Ridge,the Mantle Above