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Kenai Fjords National Park. DMoutoux & Earth Science Class of 2015. Where is Kenai Fjords National Park?. Why Visit Kenai Fjords National Park?. View arctic marine wildlife Visit fjords and glaciers Sea kayak, hike, backpack Find solitude – most of the park is inaccessible by car. - PowerPoint PPT Presentation
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Kenai Fjords National Park
DMoutoux & Earth ScienceClass of 2015
Where is Kenai Fjords National Park?
Why Visit Kenai Fjords National Park?
• View arctic marine wildlife
• Visit fjords and glaciers
• Sea kayak, hike, backpack
• Find solitude – most of the park is inaccessible by car
4 Active Volcanoes on the Kenai Peninsula
Large & frequent earthquakes One of the largest
recorded earthquakes, MR 9.2 struck nearby in 1964
How Plate Tectonics Affect the Park …
Southern coast of Alaska lies along a convergent plate boundaryo Pacific Plate subducting beneath NA Plate
Pillow Basalts from VolcanoesPlate Tectonics Affects Rock Type …
Batholith Magma that cools Underground Granodiorite (like granite, but darker)
Plate Tectonics Affects Rock Type …
Accreted Terranes Foreign land transported by the Pacific Plate and
scraped off on the coast Chert & Basalt from the ocean floor Limestone (old coral reef)
Plate Tectonics Affects Rock Type …
Produces Fractures Injected with superheated water carrying
minerals Iron, silica (quartz), arsenic, and gold
Plate Tectonics Affects Rock Type …
Half the park covered in ice Glaciers originate in the Harding Ice Field
Kenai Fjord National Park Today …
About 30,000 year ago, the entire Kenai Peninsula was covered by an ice sheet, much like Greendland or Antarctica
Kenai Fjord’s Past …
West AntarcticIce Sheet
Elevation was higher Tectonic action is causing subsidence
(slow sinking) Diagram shows subsidence following the 1964
earthquake
Kenai Fjord’s Past …
Glaciers
Mechanical Weathering & Erosion by …
Waves
Abundant snowfall Harding Icefield receives 60 feet of snow per
year. Cool summers
More snow accumulates than melts Air squeezed out as snow accumulates Becomes glacial ice in 4-10 years.
Vertical relief To allow flow downhill Tremendous weight of glacier crushes and
abrades rock Flow transport debris downhill.
How Glaciers Form
U-Shaped Valleys
Glacier-carved Features
Morraines – Piles of eroded rock left by retreating glaciers
Glacier-carved Features
Glacial Marks
Glacier-carved Features
Fjords – a long, narrow, deep glacier-carved valley filled by ocean water Found only in Norway, Greenland, New Zealand,
Chile, and Alaska
Glacier-carved Features
During an ice age, ocean water levels are much lower, so valleys can be longer
After the ice age, water level rises and fills the long, narrow, and deep u-shaped valley.
How Does a Glacier Carve a Fjord? Glaciers carve deep u-shaped valleys, but stop
at the edge of the ocean
Wave-carved Features Pounding surf erodes the coast Softer rock (limestone) far more susceptible
than basalts and granodiorite
Near Future - Embattled glaciers 3% decrease in area of Harding Ice Field in the last
16 years Estimated 40 cubic miles of glacial loss in Alaska
annually 1000’s of Years Gradual filling of fjords
Sediments accumulate at rates of up to a foot a year.
Fjords that are 600 to 1000 feet deep could be filled within the next couple thousand years.
Long Term - Continued subsidence The ocean will slowly encroach on the park.
Kenai Fjord’s Future
More, Inventory And Monitoring Network Learn about the various projects being studied. Read. National Parks Service. 19 Jan. 2013. National Parks Service. 12 Feb. 2013 <http://www.nps.gov/kefj/naturescience/index.htm>.
"Geomorphology." Geomorphology. 12 Feb. 2013 <http://svp.soic.indiana.edu/svp/4970813/FID1/html/ecosys/physical/geomorph.htm>.
"Moraine on Pederson Glacier, Aialik Bay, Kenai Fjords NP, Alaska." Panoramio. 12 Feb. 2013 <http://www.panoramio.com/photo/1268828>.
"McCarty Fjord and glacier, Kenai Fjords National Park, Alaska - aerial photograph (aat)."Panoramio. 12 Feb. 2013 <http://www.panoramio.com/photo/76217421>.
"Glaciers: Earthâs Rivers of Ice â Icebergs and Glaciers â Beyond �� �� ��Penguins and Polar Bears."Beyond Penguins and Polar Bears Glaciers Earths Rivers of Ice Comments. 12 Feb. 2013 <http://beyondpenguins.ehe.osu.edu/issue/icebergs-and-glaciers/glaciers-earths-rivers-of-ice>.
Bibliography
"West Antarctic Ice Sheet Science Traverse." : The Ice. 12 Feb. 2013 <http://waisdividetraverse.blogspot.com/2010/12/ice.html>.
"Harding Icefield." Photo Blog Photography Blog for Niebrugge Images Harding Icefield Comments. 12 Feb. 2013 <http://www.my-photo-blog.com/harding-icefield>.
"LARRY'S RAMBLE." : 2011-02-13. 12 Feb. 2013 <http://larrysramble.blogspot.com/2011_02_13_archive.html>.
"Kurt Friehauf - Alaska 2011 project description - Kenai FjordsNational Park." Kurt Friehauf - Alaska 2011 project description - Kenai FjordsNational Park. 12 Feb. 2013 <http://faculty.kutztown.edu/friehauf/alaska_2011/kenai_fjords/>.
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