Question 9 (1 point)

Question

Why does oceanic crust subduct under continental crust?

subduction zone with resulting volcano | Subduction zone, Subduction, Earth and space science

a
Oceanic crust is denser than continental crust and therefore sinks with gravity
b
Oceanic crust moves slower than continental crust, so Continental crust overtakes it.
c
Continental crust are more porous, which allows it to absorb the water in the oceanic crust
d
Oceanic crust is made of magnetic metals and are being attracted to the Core of the Earth.

Answer 1

The correct answer is:

a. Oceanic crust is denser than continental crust and therefore sinks with gravity.

Oceanic crust is primarily composed of basalt, which is denser than the granitic composition of continental crust. This density difference causes the oceanic crust to subduct beneath the continental crust at subduction zones.