7.6 The Interior of the Earth

Question 1

Basement rocks

Answer 1

The deeper granitic and gneissic parts of Earth’s continental crust.

Question 2

Crust

Answer 2

The outermost layer of the solid Earth, composed largely of granitic rock (continental crust) or gabbroic rock (oceanic crust).

Question 3

Mantle

Answer 3

The thick layer in Earth’s interior between the crust and the core, composed of dense silicate rocks such as peridotite.

Question 4

Moho

Answer 4

The crust-mantle boundary, characterized both by a change in rock composition and a change in seismic wave velocity.

Question 5

Peridotite

Answer 5

A dense iron and magnesium-rich silicate rock that is common in Earth’s mantle.

Question 6

Core

Answer 6

The innermost part of the Earth, composed mainly of iron, and divided into a liquid outer core and a solid inner core.