New oceanic crust and lithosphere are formed at ________.
A) divergent boundaries by submarine eruptions and intrusions of rhyolitic magma
B) convergent boundaries by submarine eruptions and intrusions of rhyolitic magma
C) divergent boundaries by submarine eruptions and intrusions of basaltic magma
D) convergent boundaries by submarine eruptions and intrusions of basaltic magma

Question

Quizplus · Accepted Answer

New oceanic crust and lithosphere are formed at divergent boundaries by submarine eruptions and intrusions of basaltic magma. This process is known as seafloor spreading. At divergent boundaries, magma rises from the mantle and solidifies as it cools, creating new crust and pushing the existing plates apart. The magma that forms at divergent boundaries is typically basaltic, which is low in silica and more fluid than rhyolitic magma.

New Oceanic Crust and Lithosphere Are Formed at ________