Continental crust is formed by ________.
A)melting and differentiation of oceanic crust at subduction zones
B)partial melting of mantle rocks
C)plumes of hot igneous material that rise from the core-mantle boundary to form hot spots
D)the original planetary accretion that also led to the formation of the earth's other layers
E)recycling of material in giant lava lakes in the early earth history

Question

Quizplus · Accepted Answer

Continental crust is formed by partial melting of mantle rocks, followed by differentiation and assimilation of material from the surrounding mantle. The composition of continental crust is different from that of oceanic crust, which is formed by melting and differentiation of material at subduction zones. Hotspots are responsible for the formation of volcanic island chains, but not for continental crust. Planetary accretion led to the formation of all layers of the Earth, but the differentiation process that created continental crust occurred later. The recycling of material in lava lakes is not a recognized mechanism for the formation of continental crust.

Continental Crust Is Formed by ________