NAME: ______

EROSION BY GRAVITY, ICE, AND WIND

Erosion by is called (mass wasting), and is the movement of rocks and soil due to the of gravity.

·  Factors that affect mass wasting:

o  at which the sit ( the slope the more likely to slide)

o  which lessens the and adds to the sediments

o  have greatly impacted mass movement due to and land use

·  Types of mass wasting

o  occur when rock and soil slide down slope.

o  are the down slope movement of mixed with .

o  occurs when masses of soil slips down a .

o  occurs when rock materials and soil move downhill. Creep does damage than all other mass movement processes .

are large sheets of that cover areas of land and ocean. Glaciers form over periods of time during which snow falls during the than during the summer.

·  Once glaciers reach a of about meters, they start to slowly downhill. They flow because the layers of the ice become due to the of the overlying ice.

·  The of a glacier moves faster than the sides.

·  The end of the glacier is known as the .

·  The snout of the glacier will if the rate of is greater than the rate of .

·  If flow is than melting, a glacier .

·  If flow melting, a glacier is .

There are types of glaciers:

·  glaciers form in areas

o  glacier features are mostly in nature:

o  Named after their broad valley.

·  glaciers cover a much land area and are the type that shaped area.

o  Two significant continental glaciers in the world include where collectively of all ice is located.

o  The part of continental glaciers is typically the , from which the ice then flows out in directions.

o  Chunks of glaciers that off and float in the ocean are called . Only of an iceberg sticks up above the surface.

o  glacial features are mostly in nature.

Glacial erosion:

·  - ice to rocks and pulls them downhill as they flow.

·  These plucked rocks then and erode the rocks beneath them by .

·  in the rocks, which are scratches or grooves.

Glacial deposits:

·  is and left directly by the .

o  Till deposits that build up at the of glaciers are called .

§  moraines form on the sides of glaciers.

§  moraines form in the middle of glaciers, where lateral moraines meet.

§  moraines form underneath a retreating glacier.

§  moraines form beyond the of a glacier.

·  moraines mark the advance of a glacier.

·  moraines form as a glacier becomes again after a period of .

·  is and left by melt water streams.

o  An is a thick blanket of glacial sediments deposited from the of glacial melt water streams.

are periods of time where glaciers cover most of the latitudes.

·  ice age - the most recent ice age that ended years ago and shaped most of the glacial features in .

·  ice age – ended about 100,000 years ago and covered almost the entire state of Illinois.

·  During ice ages, more of the Earth’s is frozen on land, causing ocean levels.

·  Sea level has risen about feet since the last ice age.

Erosion by is most common in climates, though erosion still causes the erosion in deserts. is the of deserts into non-desert areas.

There are main processes of wind erosion:

·  is the removal of large amounts of sediment by the wind.

o  - deep where large amounts of sediment are eroded.

o  - a layer of on the desert floor.

·  - windblown sand landforms.

o  is very fine silt created due to excessive . Loess is formed by both .

o  is a gloss that forms on rocks due to abrasion.

o  – rocks that are and angular due to abrasion.

o  are large hill shaped of sand.

§  The shape of a dune is determined by the of sand available and the of the wind.

§  The side of the dune is the side that the wind. The side is the side that faces from the wind and is .