lol Flashcards
1
Q
how are glaciers formed
A
- layers of snow fall on top of each other
- layers get compacted into ice
- can need 10 metres of snow to make 1 metre of ice
- happens over hundreds of years
- also contain rock + sediment + running water ( if melting near the surface)
2
Q
how do glaciers move
A
- ice gets thicker → much heavier
- weight forces glacier to move
- flow like water
- ice crystals slide over each other or ice melts and allows
3
Q
what’s an alpine glacier
A
- form on mountain side
- move downwards through valleys
4
Q
what’s an ice sheet glacier
A
- cover everything around them with a thick layer of ice
- form broad domes
5
Q
when do glaciers stop “flowing”
A
until they melt or reach the sea
6
Q
when a glacier breaks out in the sea what does it become
A
an iceberg
7
Q
what move faster alpine or ice sheet glaciers
A
alpine glaciers due to gravity
8
Q
when did the last ice age end
A
10,000 years ago
9
Q
what are periods of time between glacial periods called
A
interglacials
10
Q
define freeze thaw weathering
A
when water gets into the crack of a rock then freezes and expands causing the crack to get bigger until the rock splits
11
Q
what are the three distinctive features of a corrie
A
- steep back wall
- over-deepened hollow
- lip