glaciation (p1) Flashcards
what is a ribbon lake
thin lakes found at the bottom of glacial trough
why do ribbon lakes occur
glaciers erode soft rock faster than hard rock
what are corries
the product of rotational slip, hollows formed on steep back walls
why do corries occur
after snow accumulates in hollows forming small glaciers
what is freeze-thaw weathering
water flows into cracks in rocks, freezes and expands until the rock break
what is rotational slip
glaciers that are developed in hollows can move in a circular motion
what is plucking
when ice starts to move it plucks the rock away
why does plucking happen
when ice melts and re-freezes on the rocks surface
what is abrasion
when rocks that are embedded at the bottom of the glacier scrape against whats below
what is a sign abrasion has occured
striations
what is bulldozing
the glaciers pushes rocks and soil downhill as it descends
what are pyramidal peaks
when 3 or more corries develop back to back to form a sharp peak
what is an arete
2 corries developed back to back to form a knife-edge ridge
what is a hanging valley
when a smaller tributary glacier flows into a larger one but didn’t erode as much
what are glacial troughs
ice eroded v-shaped valleys at the sides and bottom - u-shaped valley
