Glacier Vocabulary (Erosional)
1. Cirque- a steep-walled semi-circular depression eroded into a
mountain peak by a glacier
2. Arete- a narrow ridge between glacial valleys
3. Horn- a sharp, pyramid shaped mountain peak formed where
three or more cirques meet
4. Col- a break in an arete (mountain pass)
5. Truncated spur- a triangular shaped rock face formed that
forms when a valley glacier cuts off the lower portion of an
arete.
6. Tarn- a small lake at the base of a cirque
7. Hanging valley- a tributary glacial valley whose mouth lies
high above the floor of the main valley
8. Crevasse- a fracture or crack in the upper 40 to 50 meters of a
glacier
9. Roches Moutonees- (resting sheep) an outcrop of bedrock
which has become elongated. Sculpted by a glacier one side is
smooth and the other is left rough
10. Striations- parallel scratches in bedrock caused by rocks
embedded in the base of a flowing glacier
Glacier Vocabulary (Depositional)
1. Drift- all sediment transported and deposited by a glacier
2. Till- unsorted sediment deposited directly by a glacier
3. Moraine- a ridge of till deposited directly by a glacier
a) lateral- forms along the side of a glacier
b) medial- merging lateral moraines of two glaciers form a
moraine in the middle of the glacier
c) ground- a melting glacier deposits till in a thin layer over a
broad area
d) recessional- deposits of till that form at the end of a glacier
as it retreats
e) terminal- the end moraine found at the farthest advance of
a glacier
4. Outwash Plain- a broad, level plain in front of a glacier where
sorted sediments can be found
5. Kame- a mound of sand formed when a stream fell through a
crevasse in a glacier
6. Kettle- pit found in a glacial deposit formed by the weight of
a chunk of ice. Usually fills with the meltwater to form a
kettle lake
7. Drumlin- long narrow mound of till with rounded tops and
teardrop shapes. (show the direction of glacial movement)
8. Rock Flour- a mixture of fine sand and silt formed by the
crushing of rock under a glacier
9. Erratics- large, isolated boulders deposited by a glacier.
Often found in peculiar places.
10. Esker- winding mound of sand and gravel formed by streams
that formed under a glacier