Small layer that makes up the majority of the Earth and surrounds a small core made up primarily of iron.

Concept that the outer surface of the Earth consists of large plates composed of the crust and the outer portion of the mantle and that these plates are slowly moving over the surface of the liquid outer mantle.

Processes that is important in reducing the size of particles that can then be dislodged by moving water and air.

Results from physical forces that reduce the size of the rock particles without changing the chemical nature of the rock.

Determined by the size of the mineral particles within the soil.

Crumbles easily.

Series of horizontal layers in the soil that differ in chemical composition, physical properties, particles size, and amount of organic matter.

Undecomposed or partially decomposed organic matter.

Level areas constructed at right angles to the slope to retain water and greatly reduce the amount of erosion.