Question

Which of the following is true of oceanic crust?

a) It makes up 71% of the earth's crust.
b) It makes up 29% of the earth's crust.
c) It averages 2,000 feet above sea level.
d) It is the type of crust between Alaska and Siberia.

Answer 1

A) it takes up 71% of the earth’s crust.

Answer 2

A. It take up 71% of the earth's crust.

Step-by-step explanation:

• The oceanic crust makes about more than 70 percent of the oceanic landmass, having a thickness of 25 to 70 kilometers thick. Its the oldest of the crust on earth. Having an average density of 2,7 g/cm, primarily being composed of denser rocks like basalt and gabbro from below.

• Mostly it's basaltic, from here all sorts of rocks are recycled to the outer land surface of the earth. Accounting for nearly 60% of the global slab of plates.

• Apart from this, the seafloor is covered with volcanic necks, trenches and deep-seated volcanoes that produce magma and the oceanic floor is composed of layers of rocks that date back to the various epi, meso, bathy, and abyssopelagic divisions.