The average composition of the oceanic crust is thought to approximate that of ________.
A) granite
B) basalt
C) peridotite
D) iron

Question

Quizplus · Accepted Answer

The oceanic crust is primarily composed of basalt, which is a type of volcanic rock that forms from the cooling and solidification of lava. It contains high levels of iron and magnesium and is denser than continental crust. Granite (A) is a type of igneous rock that makes up most of the continental crust, but it is not found in the oceanic crust. Peridotite (C) is a type of ultramafic rock that is found in the Earth's mantle and is the primary rock type of the upper mantle, but it is not found in the oceanic crust. Iron (D) is a metallic element and is not a rock type.

The Average Composition of the Oceanic Crust Is Thought to Approximate