glaciers

glacier

a large mass of moving ice (are capable of eroding, moving, and depositing of rock materials)

how do glaciers form

in areas so cold where snow stays on ground year round, piles up on itself and compacts into a giant ice mass

alpine glaciers

Form in mountainous areas (also known as a valley Glacier)

where do valley glaciers form

in valleys originally created by stream erosion

what do alpine glaciers do

form in valleys created by a stream, widens and straightens valley to a broad U shape

continental glaciers

huge, continuous masses of ice that spread out across an entire continent

what direction do glaciers move

down hill

what kind of glaciers move faster

thicker ones

what are the two ways Glaciers move

slides or flows slowly

how do glaciers slide

its weight causes the ice on the bottom to melt and it slides downhill

how does a glacier flow slowly

ice crystals within the glacier slip over each other (like a deck of cards)

how do continental glaciers erode

smooth landscape by scraping and eroding features that existed before the ice (bulldozer)

how do alpine glaciers erode

carve out rugged features in the mountain rocks

horns

sharp, pyramid-shaped Peaks that form when three or more Cirque glaciers around a mountain

cirques

Bowl Shaped depressions where glacial ice cuts back into the mountain walls

aretes

jagged ridges that form between two or more cirques cutting into the same mountain

u shaped valley

Form when a glacier erodes a river valley from its original v-shape

hanging valleys

Smaller glacial valleys that join the deeper main valley

glacial drift

the general term used to describe all material carried and deposited by glaciers

till

unsorted rock material that is deposited directly by a melting glacier

moraines

most common till deposits that generally form ridges along the edges of glaciers

stratified drift

a glacial deposit that has been sorted and layered by the action of streams or meltwater

outwash plain

a broad area in front of a glacier where streams carry sorted material and deposit it

lateral moraine

form a long sides of glaciers

medial moraine

glacier separates, middle, between glaciers with lateral moraines

ground moraine

on the ground left beneath a glacier

terminal moraine

at the end, when glacier stops moving

kettle

a depression formed when sediment builds up around a block of ice in an outwash plain

mass movement

the movement of any material, such as rock, soil, or snow, downslope

What causes ice, rocks, and soil to move down a slope

the force of gravity pulls them

Angle of repose

The steepest angle, or slope, at which loose material will not slide down slope

What are four of the characteristics of a material that will affect its angle of repose

Size, wait, shape, and moisture

landslide

Sudden, rapid movement of rock and soil down a slope

Rock fall

A group of loose rocks falling down a steep slope

lahar

Mudflows of volcanic origin, mud forms from melted snow and mixes with ash

mud flow

Rapid movement of a large mass of mud

slump

Most common type of landslide, occurs when a block of material moves down slope over a curved surface

creep

Extremely slow movement of material downhill

three factors that affect creep

Water loosen soil, plant roots wedge, burrowing animals

how does deforestation affect the likelihood of mud flows

Increases the likelihood of them happening, because the roots of trees hold soil in place

what makes glaciers flow like rivers of ice

gravity

what are the main 2 types of glacial drift

stratified drift and till