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ANTARCTICA
FINAL
172
Geology
Undergraduate 1
03/18/2014

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Term
Vinson Massif
Definition
Highest mountain in Antarctica, Ellsworth Mountain Range, 16,080 feet high.
Term
East Versus West Antarctica
Definition
East:
- 60m sea-level equivalent
- 3km thick, steep profile
- Terrestrial ice sheet
- Divergent ice flow
- Stable

West:
- 6m sea-level equivalent
- Marine-based ice sheet
- Convergent ice flow
- Ice streams
- Less stable
Term
Penguins Breeding in Antarctica
Definition
Emperor, Adelie, Chinstrap, Gentoo, King, Macaroni, Royal
Term
Antarctic circumpolar current
Definition
- Surface current
- Driven by the West Wind Drift
- Ocean current that flows clockwise from east to west
- Largest ocean current
Term
30 x 10^6 km of ice
Definition
Amount of Ice which makes up Antarctica
Term
Names of the major Subantarctic islands
Definition
- South Shetlands
- South Georgia
- South Sandwich
- Peters Island
- Heard and McDonald
Term
Major Bases of Antarctica
Definition
Main US Stations:
- McMurdo
- South Pole
- Palmer
Term
97% covered by ice
Definition
Amount of the surface of Antarctica which is covered by ice
Term
Krill
Definition
Small crustaceans consumed by whales
Term
Foredeepening of the Antarctica shelf
Definition
- Typical shelf depth 0-200m
- Inner Antarctic shelves up to 1200m deep
- Deep from isostatic depression
- Deep from glacial erosion
Term
Thermo-haline circulation
Definition
- Circulation Driven by Density Differences
- Changing Temperatures
- Changing Salinities
Term
Antarctic Bottom Water
Definition
- Most important Antarctica contribution to global oceans
- Deepest water masses in the ocean
- Far north as 50 N
- Created in the Weddell Sea, Ross Sea, and Adelie Land (East Antarctica)
- Forms on shelf as sea-ice freezes, increasing salinities
Term
Antarctic plants
Definition
- 2 Flowering plants
- Antarctica hairgrass (Deschampsia Antarctica)
- Antarctica pearlwort (Colobanthus quitensis)
- Mosses and Lichens
Term
Coriolis Effect
Definition
- Due to rotation of the Earth, currents are deflected
- Left in the southern hemisphere
Term
Ice shelves
Definition
- Floating ice extensions of glaciers
- Ice cliff seaward edge
- "The Barrier" of early explorers
Term
Albedo
Definition
- Reflecting solar energy
- Highest with white
- 80% of energy coming to Antarctica is reflected back
Term
Layers of the atmosphere
Definition
- Troposhere
- Stratosphere
- Stratospause
- Mesosphere
- Mesospause
- Thermopshere
- Exosphere
Term
What causes precipitation
Definition
- Continental effect
- Isolation from Ocean Currents
- Circumpolar Ocean
Term
Milankovitch cycles
Definition
- Incoming radiation spread differently through time
- Drives climate at:
- 100 ky, 41 ky, and 19-23 ky cycles
Term
S-waves versus P-waves
Definition
P-Waves:
- Compression waves
- Primary waves
- Faster waves
S-Waves:
- Shear waves
- Secondary waves
- Slower
Term
Evidence for plate boundaries
Definition
Antarctica is made of one plate
Term
Coldest, driest, and windiest continent
Definition
- Coldest temperature recorded on earth
- Windiest continent, 300 km/hr common
- Driest continent, <50 mm per year
Term
Hot spots
Definition
Anomalous region of volcanic activity that appear to remain stationary beneath the moving plates
Term
Cretaceous
Definition
Geological period 145 to 66 million years ago
Term
Antarctica's craton
Definition
East Antarctica, area in the interior of a continent that has been tectonically stable for a billion years
Term
Elemental abundances in the crust
Definition
98% is 8 elements: O, Si, Al, Fe, Ca, Na, K, Mg
Term
Mineral
Definition
Building blocks of rocks
Term
Cleavage
Definition
Tendency to break along flat surfaces
Term
Melting in the asthenosphere
Definition
Decreasing in seismic waves velocity from lithosphere to asthenosphere could be caused by the presence of small percentage of melt in the asthenosphere
Term
Common metamorphic rocks
Definition
Shale - Very fine
Slate - Fine
Schist - Coarse
Gneiss - Very Coarse
Term
Moho
Definition
The boundary layer between the earth's crust and mantle whose depth varies from about 3 miles (5 kilometers) beneath the ocean floor to about 25 miles (40 kilometers) beneath the continents
Term
Subduction zone
Definition
Area between sinking oceanic plate and an overriding plate
Term
Age of the Earth
Definition
4.6 billion years
Term
Shelf
Definition
Floating ice extensions which were barriers of early explorers
Term
Types of faults
Definition
Normal, reverse, and strike-slip
Term
Graben
Definition
Rifting that moves down
Term
Accreted terrain
Definition
Microplates and volcanic arches that end up "docking" onto a continent along an active continental margin
Term
Types of igneous rocks
Definition
Extrusive:
- Cools at the earth's surface
- Fine texture
Intrusive:
- Cools within the earth
- Coarse texture
Term
Stratovolcanoes and rocks
Definition
Stratovolcanoes:
-Have alternating pyroclastic and lava flows
-Violent
- Produce rhyolite and andesite
Term
Antarctic volcanoes
Definition
- West Antarctica Rift
- Mt. Erebus
- South Shetland Islands
- Peter I Island
- Buckle Island
Term
Metamorphic rock grade
Definition
Low grade - Fine grained
High grade - Coarse grained
Term
Weathering
Definition
Erosion of natural things caused by the long-term exposure to the air
Term
Grading
Definition
Determines the finesse of the grain in metamorphic rocsks
Term
Types of unconformities
Definition
Angular unconformity, nonconformity, disconformity
Term
Ice shelf
Definition
A sheet of very thick ice, with a level or gently undulating surface, which is attached to the land along one side but most of which is afloat and bounded on the seaward side by a step ice cliff rising up to several hundred meters above sea level
Term
Glacial erosion
Definition
Ice washes away the top layer of the earth and pushes it to a new low-land area
Term
Abrasion
Definition
Rock debris in base scrapes the bed
Term
Plucking
Definition
Glacier freezing to bed, moves pulls fragments away
Term
Tunnel valleys
Definition
A tunnel valley is a large, long, U-shaped valley originally cut under the glacial ice near the margin of continental ice sheets such as that now covering Antarctica and formerly covering portions of all continents during past glacial ages.
Term
Subglacial meltwater
Definition
The water beneath glacial ice
Term
Till
Definition
Sediments deposited directly by glacial ice
Term
Outwash
Definition
Sediments deposited by melwater streams
Term
Varves
Definition
True seasonal thin (cm scale) layers
Term
Erratic Boulders
Definition
a rock or boulder that differs from the Surrounding rock and is believed to have been brought from a distance by glacial action.
Term
Glacial Flour
Definition
Fine silt-sized quarts in water that gives lakes/oceans a turquoise color
Term
Glacial landforms
Definition
Cirque, Aretes, Horn, Nanutuk, Rock Drumlins, Roche Moutonnee
Term
Cirque
Definition
Semicircular hollows set in a mountain slope characterized by a steep headwall and bounded on three sides
Term
Sea level rise
Definition
Global average from 1900-2009: 1.7 mm/year
Global average from 1993-2009: 3.2 mm/year
Term
Antarctica's contribution to recent sea level rise
Definition
- Glacial meltwater
- Thermal expansion of oceans
Term
Sources of global sea level rise
Definition
- Thermal expansion of oceans
- Glacial Meltwater
Term
Antarctic explorers
Definition
Began in 1772
Term
Captain James Cook
Definition
- British
- 1772-1775
- Took 2 Ships
- Circumnavigated the globe twice
- Took a stab south 4 times
- First to cross Antarctica Circle
Term
Bellingshausen
Definition
- Russain
- 1819-1821
- Two ships
- Disputed first sighting of the Antarctica Peninsula
- First to find Peter I Island, and Alexander Island
- Sailed 145 latitude south of 60
- Visited South Shetland Islands
Term
Nathaniel B. Palmer
Definition
- US Sealer
- Sent to find good harbors for sealing
- Discovered Deception Island
- Went to 66 degrees S
- Didn't care found no seals
Term
James Weddell
Definition
- British Sealer
- 1820-1823
- Jane and Beaufroy
- Sealing in the area of the South Orkneys
- Ventured farther south
- Made it through ice pack of Weddell Sea
- Went furthest south at the time
Term
Enderby Voyages
Definition
- British Sealing and Whaling company
- Curious to geographic exploration
- Sent to voyages to Antartica
- John Biscoe
- Discovered Enderby Land
- Peter Kemp
- John Bellany
Term
John Bellany
Definition
Discovered the Bellany Islands and continental mainland south of Australia
Term
John Biscoe
Definition
- Tula and lively
- Become only 3rd to circumnavigate globa at high southern Latitudes
- Discovered Enderby Land
- Discovered Andelaide Island
Term
Jules S.-C Dumont D'Urville
Definition
- French (1837-1840)
- Commissioned for science
- Look for magnetic south pole
- L'Astrolabe and La Zelee
- Discovered:
- Mapped parts of the Eastern Antarctica Peninsula
- Parts of East Antarctica below Australia
Term
Charles Wilkes
Definition
- US (1838-1842)
- 6 ships, 400 men
- Explorer the coast of south Australia
- First to chart and surmise the extent of the continent
- Thought he was first to discover East Antarctica
Term
James Clark Ross
Definition
- British (1839-1843)
- Scientific expedition
- Study the Earth's magnetic field near the magnetic south pole
- Erebus (flag) and Terror
- Discoveries
- Ross Sea
- Victoria Land
- Transantarctic Mountains
Term
Robert F. Scott's Voyages
Definition
- 1901-1904
- Landed in McMurdo Area
- Hut Point
- Attempted South Pole
- Discovered Emperor Penguins hatch in the dead of winter
- Discovered Transantarctic Mountains
- First balloon launch in Antarctica
- Got stuck for a second year
Term
William Bruce
Definition
- Scottish National Antarctica Expedition
- 1902-1904
- Scotia - probably the most ice and seaworthy ship studying the Antarctica at the time
- Objective - Weddell Sea
- Didn't make it
Term
Charcot
Definition
- French
- Mapped 600 miles along Antarctica Peninsula
- Found wintered over in Port Lockroy
- Discovered Marguerite Bay
Term
Shackleton's expeditions
Definition
- 1907-1909 Nimrod
- Very Successful
- Discovered new farthest south
- First to reach south pole
- First to climb Mt. Erebus
- Realization that Ross Ice Shelf Changes
- Used ponies
Term
ArĂȘte
Definition
Narrow thin ridge between two cirques
Term
Glacial valley
Definition
Valley created by the movement of a glacier
Term
Hanging valley
Definition
A valley whose floor at the lower end is noticeably higher than the floor of the main valley at the junction
Term
Horn
Definition
Spire between 3+ cirques
Term
Fjord
Definition
Glacial valley flooded by an arm of the ocea
Term
Patemoster lakes
Definition
Series of small lakes connected by a small meltwater stream within an empty glacial valley
Term
Nanatuk
Definition
Isolated mountain sticking up through the ice sheet (becomes a horn)
Term
Rock drumlins
Definition
Smooth streamlined hills elongated parallel to the direction of former ice flow
Term
Roche moutonnee
Definition
Similar to a rock drumlin but truncated at the down ice end
Term
Drumlins
Definition
An elongate hill formed when a glacier flows over and reshapes a mound of till
Term
Eskers
Definition
Long snake-like ridges formed by deposition in a stream that flowed on, within, or beneath a glacier
Term
Types of moraines
Definition
- End(terminal) moraine
- Lateral moraine
- Medial moraine
- Ground moraine
Term
Megascale glacial lineations
Definition
Long narrow ridges of till alligned parallel to the ice flow and usually found in groups
Term
Kettle lake
Definition
A depression in outwash created by melting of a large chunk of ice buried in the till by a receding glacier
Term
Paraglacial landforms
Definition
Processes, conditoins, areas, climates, and topographic features at the immediate margins of former and existing glaciers and ice sheets, and influenced by the cold temperature of the ice
Term
Climate change
Definition
- Happens in cycles
- Places current observations into historical perspective
Term
Weather versus climate
Definition
Weather: condition of the atmosphere at any particular time and place
Climate: the "average weather"; the accumulation of daily and season weather events over a long period of time
Term
Major Antarctic glaciations
Definition
- Carboniferous - Permian Glaciation
- Modern Cenozoic Glaciation
Term
Milankovitch
Definition
Cycles of 23,000, 41,000, and 100,000 years
Term
Bond cycles
Definition
3 kyr cycles
Term
Little Ice Age
Definition
Best expressed in the South Shetland Islands
Term
Ice cores
Definition
Ice cores are cylinders of ice drilled out of an ice sheet or glacier
Term
El Nino/La Nina and Antarctica
Definition
- Periods of warmer temperatures along the Equatorian coast
- Brings changes Antarctic weather too
Term
Drivers of climate change
Definition
- Solar Output
- Ocean-Current changes
- Wind pattern changes
- Greenhouse gases
Term
Major greenhouse gases
Definition
- Carbon Dioxide
- Dust
- Sea Salts
- Pollutants
Term
CO2
Definition
Carbon Dioxide, comes from burning fossil fuels (14C)
Term
Amounts of CO2 in the atmosphere
Definition
Increasing, oceans remove 26% of CO2 emissions
Term
CO2 sources
Definition
Human activity
Term
Volcanoes and climate
Definition
- Cool the earth
- Put ash and aerosols into the stratosphere
Term
Mt. Pinatubo
Definition
0.2 C to 0.5 C cooling
Term
Krill changes over last 50 years
Definition
Krill have been decreasing
Term
Orogeny
Definition
Orogeny refers to forces and events leading to a large structural deformation of the Earth's lithosphere due to the engagement of tectonic plates
Term
Oldest rocks in Antarctica
Definition
4 billion years old
Term
SWEAT hypothesis
Definition
East Antarctica and Laurentia (early North America) were joined prior to 650-750 million years ago
Term
Gondswana
Definition
In paleogeography, Gondwana, also Gondwanaland, is the name given to the more southerly of two supercontinents that were part of the Pangaea supercontinent that existed from approximately 510 to 180 million years ago
Term
Drilling programs in Antarctica
Definition
- Cape Roberts Project
- AnDrill
- ShalDrill
Term
Northofagus
Definition
Antarctic tree
Term
Antarctica glaciations
Definition
- Late paleozoic
- Late cenozoic
Term
Gateways
Definition
Small passages of open ocean between continents
Term
Bowen's Reaction Series
Definition
Explains why some types of rocks are found together, why some some are never found together
Term
Upwelling Zones
Definition
Around Lows:
- Ascending air cools, holds less moisture
Around highs:
- Descending air warms, holds more moisture
Term
Hadley Cells
Definition
- Air rises at the equator
- Goes towards poles but some sinks
- Similar movement originationg from the poles
- Sets up Hadley Cells
- 0, 30, 60, 90
- 0 and 60 diverge, 30 and 90 converge
Term
Katabatic winds
Definition
- Cold air sinks
- Slope of the ice sheet - descending winds
Term
Napier orogeny
Definition
Period of time 4 billion to 3.8 billion years ago
Term
Layers of the Earth
Definition
Crust, Mantle, Outer Core, Inner Core
Term
Common gases in the atmosphere
Definition
Nitrogen - 78%
Oxygen - 21%
Argon - 0.93%
Carbon Dioxide - 0.037%
Term
Sea-level rise due to Antarctica melting
Definition
Antarctica is a major contribution to the rise in sea level because of melting glaciers
Term
Lake Vostok
Definition
Largest subglacial lake (14,000 km^2)
Term
Pelagic
Definition
- Ice Fish
- Silverfish
- Krill
Term
Sea ice formation
Definition
Sea ice formed = higher salinity
Sea ice melted = lower salinity
Term
Why is it cold in Antarctica?
Definition
- Pole Position
- High elevation
- Albedo effect
- Isolated Oceanographically
Term
Subduction zones of Antarctica
Definition
Major one is the Antarctic Peninsula
Term
Dikes
Definition
- Cuts across bedding
- Discordant
Term
Water cycle
Definition
Sometimes, evaporation does not always come from water, it often comes from land.
Term
Firn
Definition
Snow converts to firn after it becomes granular ice
Term
Glacial Ice
Definition
Glacial ice is formed after snow becomes granular ice, then firn, then glacial ice
Term
Sublimation
Definition
Precipitation from Solid to gas (over land)
Term
Water of the Earth
Definition
- Mostly in Oceans
Term
Water in Antarctica
Definition
- Most Water
- Most Evaporation
Term
Ice Cap
Definition
Continental glacier covering less than 50,000 km^2
Term
Ice Sheet
Definition
Glacier covering more than 50,000 km^2
Term
Glacial motion
Definition
- High precipitation = high speeds
- Glacial surges: periods of time with rapid glacial flow
Term
Basal slip
Definition
Entire glacier slides over bedock
Term
Plastic flow
Definition
Glacier deforms as viscous fluid
Term
Ice falls
Definition
Avalanches of ice, streaming down the side of mountains
Term
Zones of accumulation/ablation
Definition
Accumulation - More snow and ice falls in the winter than melts in the summer
Ablation - More snow and ice melts in the summer than falls in the winter
Term
Calving
Definition
- Icebergs breaking off into the ocean
- Dominant form of ablation in Antarctica
Term
Icebergs
Definition
- Calve from the front of the glacier
- Drift with the wind/current
Term
Tabular icebergs
Definition
Flat icebergs shaped like slabs/tabs
Term
Classification of glaciers
Definition
- Thermal
- Morphologic
- Dynamic
- Tidewater
Term
Piedmont glaciers
Definition
Confined in upper reaches but at terminus discharges as broad radially flow - like a lobe
Term
Wilhans Ice Stream
Definition
Major ice cream in North West Antarctica
Term
Recent temperature trends in Antarctica
Definition
One of the fastest warming places on the planet
Term
Ocean temperatures last 80 years
Definition
The southern ocean has gained 1 degree C over the last 80 years
Term
Sea ice changes last 50 years
Definition
- Spatial differences
- Increasing:
- Ross Sea
- Slightly in the Weddell and Indian Ocean
Decreasing:
- Amundsen
- Bellinghausen
Term
Tidewater glaciers change last 50 years
Definition
85% of the 244 glaciers surveyed retreated in the Antarctic Peninsula over the last 50 years
Term
Ice shelf collapse and causes
Definition
Rapidly retreating from:
- Increased temperature
- Basal melting from increased ocean temperatures
Term
Ice mass changes and measurements
Definition
- Melting ice
- Sea ice - no changes in sea level
Term
Race to the Pole
Definition
Amundsen and Scott raced to reach the South Pole first, Amundsen won
Term
Amundsen
Definition
- Norwegian
- 1910-1912 Fram
- Race to the south pole
- Small light swift
- Discovered Northwest Passage
- Used Dogs
Term
Country claims on Antarctica
Definition
- New Zealand
- Britain
- France
- Australia
- Norway
- America and USSR claim the whole continent
Term
SCAR
Definition
Established to continue the coordination of scientific activity on Antarctica after IGY
Term
Operation Highjump
Definition
- Post WWII as part of demobilization of military
- 13 ships, 23 aircraft, 4700 personnel
- Mapped parts of Antarctica
- Rewards not commiserate with effort
Term
Schwbenland Expedition
Definition
- Mapping via 2 airships
- 7 days, 16 trips
- Mapped 600,000 km^2
Term
Maudheim expedition
Definition
- Norwegian-British-Swedish
- International Science Expedition
- Established a research station
Term
Deepfreeze operations
Definition
- USA
- Largely paved the way for planned IGY activities
- Deepfreeze I established McMurdo
- Deepfreeze II established South Pole
Term
IGY
Definition
- Idea originated in 1950 between American and British Scientist
- Established 50 reserach stations
- Launch of Sputnik
- Laid framework for later international negotiations
Term
Antarctic Treaty
Definition
- Complex of arrangements made for the purpose of regulating relations among nations in the Antarctic
- Promotes peace
Term
Annexes to the Antarctic Treaty
Definition
- Environmental Impact Assessment
- Conservation of Antarctica Fauna and Flora
- Waste Disposal and Waste Management
- Prevention of Marine Pollution
- Area Protection and Management
- Liability arising from environmental emergencies
Term
Specially Protected Areas
Definition
- First established in 1964
- 3 Categories
- Antarctic specially Protected Areas
- Antarctic specially managed areas
- Historic sites and monuments
- Need a permit to enter
Term
Fishing in Antarctica
Definition
"nothing in the Treaty shall...affect the rights...of any state... with regard to the high seas within that area"
Term
Patagonia Toothfish
Definition
A really big fish which was illegal to catch
Term
Challenges in Antarctica
Definition
- Waste
- Managing Tourism
- Global Warming
- Ozone Hole
Term
Tourism in Antarctica
Definition
- Reached a peak in 2007-2008
- 32, 637 by sea
- Decline due to the global economy and banning of heavy fuels
Term
Ozone Hole
Definition
- Ozone protects us from UV radiation
- Use of choloflourocarbons depletes levels of ozone
- Saw expansoin of ozone hole in the 1980's
- CFC's banned by treated starting in September 1987
Term
Chloroflourocarbons
Definition
CFCs, aerosol cans, reactions destroying the ozone
Term
Mitigation of Ozone Hole
Definition
Reached as large as 11.4 million km^2
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