Erosion
The process by which natural forces move weathered rock and soil from one place to another.
Deposition
Occurs where the agents of erosion, deposit, or lay down, sediment.
Sediment
The material moved by erosion.
Mass Movement
Any one of several processes by which gravity moves sediment downhill.
Landslide
The most destructive kind of mass movement, which occurs when rock and soil slide quickly down a steep slope.
Mudflow
The rapid downhill movement of a mixture of water, rock, and soil.
Slump
When a mass of rock and soil suddenly slips down a slope.
Creep
The very slow downhill movement of rock and soil.
Runoff
Water that moves over Earth's surface.
Rills
A tiny groove in soil made by flowing water.
Gully
A large channel in soil formed by erosion.
Stream
A channel through which water is continually flowing downhill.
Tributary
A stream or smaller river that feeds into a main river.
Flood Plain
The flat, wide area of a land along a river.
Meander
A loop-like bend in the course of a river.
Oxbow Lake
A meander that has been cut off from the river.
Alluvial Fan
A wide, sloping deposit of sediment formed where a stream leaves a mountain range.
Delta
Sediment deposited where a river flows into an ocean or lake builds up a landform.
Groundwater
The term geologists use for this underground water.
Glacier
Any large mass of ice that moves slowly over land.
Continental Glacier
A glacier that covers much of a continent or large island.
Valley Glacier
A long, narrow glacier that forms when snow and ice build up high in a mountain valley.
Ice Age
Times in the past when continental glaciers covered large parts of Earth's surface.
Plucking
A process when a glacier flows over the land it picks up rocks.
Abrasion
The grinding away of rock by other rock particles carried in water, ice, or wind.
Deflation
Wind removes surface materials.
Headland
A part of the shore that sticks out into the ocean.
Beach
An area of wave-washed sediment along a coast.
Longshore Drift
When waves repeatedly hit the beach, some of the beach sediment moes down the beach with the current.
Loess
Fine, wind-deposited sediment.
Spit
Formed as longshore drift deposits sand along the shore.
Sea Stack
Left standing when sea arch collapses.
Sea Cave
Formed as wave action hollows out the cliff.
Sea Arch
Formed when sea caves on either side of a headland join.
Sandbar
Formed by wave action.
Desert Pavement
Forms when wind blows away the smaller sediment or sand and leaves behind larger rock, too big to move, leaving hard, flat surface.