| Terms |
Definitions |
|
Lacustrine
|
lake
|
|
till
|
unsorted glacial sediment
|
|
Ground Moraine
|
unsorted
material left
beneath the
glacier when
the ice melts
• Both glacier
types
|
|
Shrinking
|
Many Alpine Glaciers are
|
|
Recessional moraine
|
Till marking glacial retreat.
|
|
Glacial Erratic
|
large boulders
transported by glaciers
|
|
Glacial trough
|
The movement of glaciers.
|
|
Abrasion
|
wind -carried sand polishes rock
|
|
glacier
|
a moving river of ice
|
|
Eskers
|
(glacial deposit) Long winding ridge of sand and gravel
|
|
most glacier deposits are...
|
scratched and semi-round
|
|
Ventifacts
|
Rocks shaped by wind- blown sediments.
|
|
paternoster lake
|
string of connected glacial lakes
|
|
Drumlins
|
a. asymmetrical hills composed of till. b. Probably molded in the zone of flow.
|
|
Two types of glaciers
|
valley glaiers
continental glaciers
|
|
Serac
|
standing ice tower. Common in icefalls
- also very dangerous.
|
|
Accumulation
|
addition of snowfall, compaction and recrystallization
|
|
Alluvial Fans
|
A sloping deposit of sediment
|
|
Drumlins
|
Tear drop shaped land features; unsorted.
|
|
Crevasses
|
Cracks in surface ice in glaciers going down steeper gradient.
|
|
Erratics
|
A large bolder transported by a Glacier.
|
|
drumlin
|
a long, smooth, canoe-shaped hill that is usually found in groups, shaped by an advancing glacier
|
|
esker
|
result of deposits made by glacial melt waters running through tunnels under the glacier
|
|
Col
|
arete that takes on a saddle shape
|
|
Aretes
|
The ridges between glacial valleys can become very narrow, forming knife-like features
|
|
wedging
|
ice getting into the ground and creating cracks
|
|
Mountain glaciers
|
accumulated snow at colder HIGHER elevations, snow turns to ice and flows to lower elevations where it melts
|
|
stratified drift
|
sediments laid down by glacial meltwater
|
|
glacial drift
|
the material deposited in association with a glacier
|
|
A land-form formed when an advancing glacier overruns its old moraines
|
drumlin
|
|
isostasy
|
balance of the earth's crust which means if one area, the cause is sinking, another area, the crust is rising. isostatic rebound - man cause for earthquakes in ohio.
|
|
Striations
|
Scratch marks gouged into the bedrock by rocks suspended in glacial ice
|
|
plastic
|
lower 60 m, ductile flow heals cracks
|
|
kame
|
a symmetrical hill of sediment formed under crevasses after ice melts
|
|
isostatic rebound
|
removal of ice cause crustal uplift
|
|
Snow line
|
altitude at which snow accumulates on a mountain
|
|
mass and size
|
what two characteristics of glaciers make its distinct and often stunning evidence for their passing
|
|
Moulin
|
a nearly vertical channel in the ice that is formed by flowing water
|
|
Erosion by plucking
|
occurs when rocks disaggregate along pre-existing fractures, which are commonly enhanced by freeze and thaw of meltwateror by pressurized meltwater or ice that is injected into the cracks.
|
|
Medial Moraine
|
A moraine formed when two advancing valley glaciers come together to form a single ice stream, forms in the middle of the glacier
|
|
Iceberg
|
a mass of ice floating in the ocean
|
|
Erosion
|
process in which the glacier or melt water removes pieces rock from the earth's crust
|
|
kettle
|
a small deposition that forms when a chunk of ice is left in glacial till
|
|
glacier effect on midwest
|
erosional and depositional features throughout landscape, reason illinois is so flat, great lakes are the u-shaped glacial valleys
|
|
glacial valley
|
A U-shaped valley formed by glacial erosion
|
|
hanging valley
|
when a small tributary glacier is unable to erode as deeply as the large glaciers they join
|
|
Plucking
|
the process where a glacier flows over land and it picks up rocks
|
|
continental features
|
kame: made of glacier till. kettle: depressents that have water (geauga/punderson). marines: hills of ridges of till. drumlin: teardropped shape hill. esker: made of sand and is like a marine.
|
|
Tarn
|
a small lake (in mountain) occupying a cirque or trough. Usually occupies only a couple of acres
|
|
lateral moraines
|
form on the sides of the glacier
|
|
ice ages
|
times in the past when glaciers covered large parts of the worlds surface
|
|
Cirque
|
basin at the head of a glacial valley
|
|
What are the layers of the atmosphere?
|
Top: ThermosphereMesosphereSratospheretrophosphere(closest to our sky)
|
|
Moraines
|
A deposit of till left behind when a glacier retreats.
|
|
ice cap
|
a glacier that is less than 50,000 square kilometers in area
|
|
Medial moraines
|
The middle of the glacier, when the lateral moraines form they make a medial moraine
|
|
Wind Deposits are of Two Distinct Types
|
loess and dunes
|
|
continental glacier
|
a glacier that covers much of a continent or large island
|
|
crevasse
|
a fracture or crack in the upper 40-50 meters of a glacier
|
|
interglacial features
|
warmer periods of time btwn ice ages currently are living in an interglacial period and the earth should naturally warm for the next 80,000 years.
|
|
Self Arrest
|
a technique that climbers use to stop from falling down a slope by digging an ice ax into the snow
|
|
Polar glaciers
|
ice in a ______ always maintains a temp well below its melting point
|
|
What are the parts of a wave?
|
Top: CrestBottom: Troph
|
|
Internal plastic flow-
|
slow movement of a glacier in which ice crystals slip over each other
|
|
Zone of Fracture is Located...
|
near the surface of a glacier
|
|
Glacial erosion: explain proccesses and describe resulting landforms; Abrasion
|
Abrasion- scraping and grinding (rock flower and striations)
|
|
End Moraine
|
A ridge of till at the leading edge end of a stationary glacier.
|
|
How is glacial load transported?
|
Suspension (material stuck in the ice)
|
|
Alpine Glacier
|
a glacier that moves down from a high valley
|
|
Describe the Green House Effect?
|
Suns short waves heat the ground--warm air raises and heats the greenhouse.--long wave lengths radiated to the atmosphere.
|
|
How Did Early Scientists Explain Bubble Rock in Acadia National Park?
|
came from God (the great flood)
|
|
Where is the fastest flow of glaciers?
|
in the center, at the top
|
|
Describe the characteristics of a driftless area
|
This is an area in southwestern Wisconsin that the glacier went around. The hills are steeper and the land is not flat there.
|
|
Any Theory the Attempts to Explain the Causes of Glacial Ages Must Answer...
|
what causes the on set of glacial conditions? what caused the alternating glacial and interglacial stages that have been documented for the Pleistocene epoch?
|
|
ablated
|
lost ice
|
|
Types of deposition
|
drift
till
outwash
loess
erratics
|
|
Alpine
|
Form in mountainous areas
|
|
compress
|
squeeze or press together
|
|
terminus retreats
|
When wastage > accumulation
|
|
land cover
|
10%, ice age= 30%
|
|
end moraines
|
form at stable toe
|
|
Morain
|
unsorted till. Lateral, Medial, Recessional, Ground, end
|
|
Direction
|
grooves and striations indicate the ___________ a glacier moved
|
|
alpine glaciation
|
glacier in the mountainous regions
|
|
ice front
|
the end of the glacier
|
|
horn
|
a pyramid-like mountain with hollowed out faces in it from glaciers
|
|
firn
|
Partially compacted and refrozen snow which has yet to become a glacier
|
|
glacial outwash
|
meltwater...muds removed, size GRADED and stratified, abraded, rounded...dominated by sand and gravel
|
|
outwash
|
material deposited by melt water streams: some sorting occurs
|
|
tidewater glaciers
|
valley glaciers that flow into sea
|
|
Eskers-
|
long winding ridge of gravel and course sand deposited by a glacier
|
|
arete
|
sharp ridge formed by two glaciers eroding away on opposite sides; separating two cirques
|
|
Loess
|
extensive blankets of silt that is carried by the wind in suspension
|
|
Snowline
|
The lowest elevation in a particular area that remains coverd in snow all year. At the poles, the snowline occurs at sea level.
|
|
kinds of glaciers
|
valley glacier and continental glacier
|
|
Terminal Moraine
|
The farthest advance of a glacier
|
|
moraine
|
rock debris deposited by glaciers form features called
|
|
Icefall
|
broken glacial surface caused by steep inclines. (Very Dangerous)
|
|
Drift
|
any material carried and deposited by a glacier
|
|
Kettle Holes
|
If depressions form underneath a glacier and remain after the glacier is melted then water filling these depressions become small lakes where fine‐grained sediment is deposited.
|
|
hanging glaciers
|
cling to mt sides; wide not long
|
|
Moraine-damned lakes
|
Occurs when a terminal moraine has prevented some meltwater from leaving the valley.
|
|
a pile of glacier deposits that looks like an inverted spoon
|
drumlin
|
|
fiord
|
forms when sea levels rise, filling a valley once cut by a glacier in a coastal region
|
|
The Elevation Above Which Snow Remains Year Round
|
snow line
|
|
ice fall
|
region of crevasses and ice pinnacles (where blocks shear off)
|
|
Which movement of glacier occurs upper 150 feet and does not flow like taffy?
|
Brittle flow
|
|
Where are there continental glaciers?
|
Northern Canada, Greenland, Antarctica
|
|
Erratic
|
Big rock carried and deposited by a glacier.
|
|
Internal Flow
|
results from the deformation of the ice crystal structure, crystals slide over each other like a deck of cards
|
|
U
|
A ______ shaped valley is a valley that has steep sides and a flat bottom
|
|
basal slip
|
Sometimes the weight of the overlying ice
causes the ice at the bottom of a glacier to
melt and refreeze forming either a layer of
meltwater or a slushy layer of water and
sediment. In each case, friction with the
bottom is reduced causing the glacier to
move forward.
|
|
ice shelves
|
ice sheets that extend over the sea and float on water
|
|
Chatter Marks or Crescentic Gouges
|
half-mooned shaped fractures on glaciated rock surfaces caused by the irregular, jerky motion of a glacier
|
|
2 types of glacier
|
1. vallley glacier (alpine) 2. continental (ice sheet/ice cap)
|
|
Valley Glacier
|
A long, narrow glacier that forms when snow and ice build up in a mountain valley
|
|
Zone of fracture
|
Upper ~ 150 feet of the glacier
|
|
Glacial Till
|
What makes up moraines, which are an unsorted mix of rock materials
|
|
stratagraphic
|
most common oil map in NE Ohio also produces the least amount of oil.
|
|
Lake and River Ice
|
Ice forms later and disappears earlier
|
|
cryoconite
|
a depression made in the snow due to rock absorbing heat
|
|
Lateral Moraine
|
Glacial deposit on the side of a valley glacier on valley walls
|
|
kettle lakes
|
form in large numbers in the kettle holes or moraines and outwash plains
|
|
Star dune
|
Dune with a star shape, formed by wind that blows in from many directions
|
|
Hanging valleys
|
occur due to the more rapid erosion in the main glacier channel versus tributary channels, causing a large vertical difference between the channels once the glacier melts. Hanging valleys often contain waterfalls like Bridal Veil Falls in Yosemite
|
|
zone of accumulation
|
The process by which the glacier adds mass
|
|
compressant (type of stress)
|
rock layers are pushed tgthr occurs when large crustal plates collide.
|
|
5 acres
|
amount of cape cod lost every year due to erosion
|
|
it's left in place
|
what happens to a terminal moraine if the glacier retreats
|
|
depositional landforms created by alpine glaciation
|
(what glaciers produce when they melt and deposit their debris cargo at the glacier's terminus) glacial drift: stratified drift, till; moraines: lateral moraine, medial moraine, terminal moraine
|
|
glaciers carry lots of sediment
|
some falls from cliffs, some from erosion of substrate
|
|
A ______ is a stream of ice that flows between a steep rock walls from a place near the top of a mountain valley.
|
Answer: Valley Glacier
|
|
What causes a wave to break?
|
Trips over bottom. When depth to the bottom is 1/2 the wave length.
|
