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Rashid [163]
4 years ago
8

The oceanic crust is composed mostly of which substance. why?

Biology
2 answers:
Ierofanga [76]4 years ago
5 0
 It is primarily composed of mafic rocks, or sima, which is rich in iron and magnesium. It is thinner than continental crust, or sial, generally less than 10 kilometers thick; however it is denser, having a mean density of about 2.9 grams per cubic centimeteras opposed to continental crust which has a density of about 2.7 grams per cubic centimeter.
kotegsom [21]4 years ago
3 0
It is composed of several layers, not including the overlying sediment. The topmost layer includes lavas made of basalt.
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