Question

which of these describes the outcome of the collision between oceanic and continental crust?
a the two portions of crust will slide past each other, side by side.
b the continental crust will be melted and become magma.
c the oceanic crust will subduct beneath the continental crust.
d the two portions of crust will stop moving.

Explanation:

To solve this, we analyze each option:

• Option A: Sliding past each other is a transform boundary, not oceanic - continental collision. Eliminate A.
• Option B: Continental crust is less dense than oceanic crust and is not easily melted in this collision. Oceanic crust is more likely to subduct and be melted. Eliminate B.
• Option C: Oceanic crust is denser than continental crust. In a collision between oceanic and continental crust, the denser oceanic crust subducts (goes under) the less dense continental crust. This is correct.
• Option D: Tectonic plates (and thus crusts) are in constant motion due to convection currents in the mantle. They don't stop moving in a collision. Eliminate D.

Answer:

C. The oceanic crust will subduct beneath the continental crust.