glacial modification

Question 1

glacier

Answer 1

large natural accumulation of land ice affected by present or past motion, moves in response to gravity so downward. motion occurs because the ice loses its rigidity and becomes plastic

Question 2

what is the density of water

Answer 2

1 g/cm 3

Question 3

what are the stages of snow

Answer 3

snowflakes - ice granules - firn - ice

Question 4

ice age

Answer 4

a period of millions of years characterized by intermittent glacial occupation of large areas of high and mid latitudes

Question 5

glacial periods

Answer 5

period where glaciers advance, colder and drier than interglacial periods

Question 6

interglacial period

Answer 6

warmer periods where glacier retreat

Question 7

phanerozoic 3 major glaciations

Answer 7

andean
karoo
cenozoic

Question 8

types of glaciers

Answer 8

constrained (mountain/ alpine)
unconstrained (continental)

Question 9

what is a constrained glacier

Answer 9

shape and flow pattern strongly dependent on underlying topography

Question 10

what is an unconstrained glacier

Answer 10

shape and flow patter is mostly independent of underlying topography

Question 11

glaciers move by

Answer 11

internal deformation
basal sliding

Question 12

zone of ablation

Answer 12

more ice melts than accumulates as snow

Question 13

till

Answer 13

unstratified mixture of rock fragments of all sizes

Question 14

types of moraines

Answer 14

• end
• terminal
• recessional
• interlobate
• push/ squeeze
• ribbon

Question 15

drumlin

Answer 15

oval shaped hills composed of glacial till (look like little speed bumps)

Question 16

esker

Answer 16

sediments deposited by glacial streams (look like a very big string is under the ground)

Question 17

glaciolacustrine

Answer 17

sediments originate from glacier and deposited in a lake

Question 18

glacial lake agassiz

Answer 18

largest of all marginal lakes
contained lake of the woods, lake winnipeg, lake manitoba

Question 19

glacial pluking

Answer 19

glacier pulls large rocks or boulders from the ground as it moves and drops it later on as it melts out of the glacier (glacier erratics)