Name ____________________________ Science 1 2 3 6 7
Glacier Computer Lab
Date _______________________
(These sites are also linked on my webpage)
Go to this Glacier Information Website:
http://www.as.uky.edu/academics/departments_programs/EarthEnvironmentalSciences/
EarthEnvironmentalSciences/Educational%20Materials/Documents/elearning/module13s
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1.
What is the key to building glaciers?
summer will build glaciers.
More snowfall in winter than melts away in
Types of Glaciers:
2.
What is the difference between confined and unconfined glaciers?
Confined
glaciers are limited in their forms by local topography while unconfined are typically
larger and flow over the land without being bound by the shape of the land.
3.
Give two examples of unconfined glaciers.
Ice caps- ex. Islands in Arctic polar
region; Ice sheet- greater than 50,000 km area- ex. Greenland and Antarctica.
Anatomy of Glaciers:
4.
How is a glacier’s accumulation zone different from its ablation zone?
High on
the glacier, more snow, firn, and ice add more mass to the glacier in the
accumulation zone, while at the base of the glacier, in the ablation zone, there is
loss of ice due to melting and sublimation.
Glacial Movement:
5.
What force causes ice to move down slope?
Gravity by: 1) internal deformation
of ice by pressure of overlying ice and 2) basal sliding of ice mass along the ground
due to slight thaw at base
Glacial Erosion:
6.
7.
8.
How can a glacier made of ice erode a landscape made of rock?
2 main mechanisms: 1) quarrying (plucking) and 2) abrasion- pluck, scrape, and
gouge landscape
Explain quarrying: Glacier freezes to rock landscape, gains leverage to pluck rock
as it moves over, especially jointed or fractured bedrock.
Explain abrasion:
once the glacier carries the rock debris, it can scrape the
underlying landscape and gouge softer rocks.
Glacial Erosional Features:
9.
Explain striations:
Grooves cut into bedrock surface as frock fragments are
carried along at the base of a glacier. Striations show direction glacier was moving
10. Compare U-shaped and V-shaped valleys:
Rivers erode straight down, creating
V-shaped valleys; however, glaciers erode broadly, creating steep sides and wide
broad floor.
Name ____________________________ Science 1 2 3 6 7
Date _______________________
11. Explain hanging valleys:
tributary glaciers that don’t cut as quickly into bedrock
as the main glacier, so when the glacier recedes, leave a flat valley that ends at a
steep drop often forming waterfalls from hanging valley.
Glacial Sediment:
12. What is till and how does it form?
Unsorted mix of clay, sand, pebbles, and
boulders formed when glacial ice melts, leaving debris (sediment)
13. What is an erratic and how does it form?
Glacial sediment that travels far
from its bedrock point of origin and differs dramatically from the bedrock where it is
deposited.
Glacial Depositional Features:
14. What is a moraine and how does it form?
Deposits of till left behind from
glacial melting; named based on where they form relative to glacial anatomy
(terminal moraine, medial moraine)
Model:
15. What factors make a glacier grow?
temperature decreases (colder)
Precipitation increases (wetter) and
16. What factors make a glacier shrink?
temperature increases (hotter).
Precipitation decreases (drier) and
Go to this Glacier Interactive Simulation Website:
http://phet.colorado.edu/simulations/sims.php?sim=Glaciers
17. What happens when you adjust the two climate conditions?
When you
decrease temperature and increase snowfall, the glacier grows. The glacier shrinks
when temp increases and snowfall decreases.
18. What do the black specks in the glacier represent?
Glacial till (drift, debris) from
quarrying and abrasion, left behind as till and/or moraines.
19. Explain how the distribution (arrangement) of black specks changes from the
top of the glacier to the toe of the glacier?
The further down the glacier, the
black specks increase. There are fewer specks in the accumulation zone and more
in the ablation zone.
20. What happens to the black specks when the glacier recedes (melts and gets
shorter)? What does this form? The black specks are left behind on the land and
form till deposits and moraines.
drift is a general term for all glacial sediment