Earth's Interior and Weathering

Vocabulary related to the structural layers of the Earth and the various processes of weathering.

Crust

The solid outer cover of the earth that envelopes its interior portion, sustains life, and is thicker under continents and thinner under the oceans.

Mantle

The layer in between the crust and the core with an average thickness of about $2,900\,km$ and a density that increases with depth.

Mohorovicic Discontinuity

The boundary that separates the crust from the mantle, named after the scientist Andrija Mohorovicic.

Core

The innermost shell of the earth, about $3,500\,km$ thick and made up of metals, often referred to as the metallic core.

Outer Core

A layer of the core mainly composed of iron and existing in a liquid state.

Inner Core

The innermost part of the core composed of nickel and iron; it behaves like a solid due to the extremely high pressure of the outer shell.

Earth's Temperature Gradient

The rate at which the temperature within the earth rises as depth increases, specifically $1^{\circ}C$ for every $32\,metres$.

Weathering

The process by which rocks exposed on the earth's surface are broken down, decaying or disintegrating in place.

Water Action (Weathering)

A weathering process where water collects in rock pores, freezes, and expands, widening cracks until the rocks disintegrate.

Wind Abrasion

A process where air loaded with sand strikes against rock surfaces, especially during storms, causing the rock to be broken into smaller pieces.