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| Title |
Characteristics and Rates of Thermal Erosin Barrow, Alaska
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| Author(s) |
Lewellen, Robert I.
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| Advisor(s) |
Griffiths, Thomas M.
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| School/Department |
Department of Geography
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| Institution |
University of Denver
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| Degree Type |
Master's
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| Degree Name |
M.A.
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| Type of Resource |
text
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| Degree Date |
1965-12
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| Digital Origin |
reformatted digital
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| Rights Statement |
All Rights Reserved
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| Reason for Restrictions |
No restrictions
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| Type of Restriction |
No restrictions
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| Keyword(s) |
Geology
Geography
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| Abstract |
In the vicinity of Barrow, Alaska, the tundra-covered mainland of the Arctic Coastal Plain is eroding thermally. The upper several meters of perennially frozen ground consists of fine-grained, ice-cemented sediment, large quantities of buried peat, and massive ice wedges. The seasonally thawed soil is approximately 40 cm deep. The mechanisms of erosion include: undercutting, the formation of thermo-erosional niches and collapse, slumping and saturated flow of thawed soil and exposed sediment, and ice-wedge depletion. Rates of erosion have been determined for a tundra stream, along 75 km of the Elson Lagoon coastline, and along selected lake shorelines. The measurements were made from aerial photography compiled over the past 16 years. Locally, the shorelines are retreating differentially as a function of cliff exposure, sediment composition, currents, depth of offshore water, and wind generated waves. Erosion along selected portions of the Elson Lagoon shoreline ranges from amounts too small to be measured effectively, along sheltered areas, to 10.4 meters per year by Olkralik Point where the shore is exposed to the Beaufort Sea. Rate of shoreline retreat for selected points on the oriented lakes ranged from less than 0.3 to 3.6 meters per year. Many of the lakes are being revegetated. The Footprint Creek area was studied for changes caused by an increase in watershed area and precipitation. A nick point retreat rate of 3 meters per year was measured between 1952 and 1962. A rate of 28 meters per year for 1962 and 1963 was measured after heavy precipitation.
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| Handle |
http://hdl.handle.net/10176/codu:38545
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| Attached Files |
| Name |
Description |
MIMEType |
Size |
Downloads |
du_mas_1966_Lewellen.pdf
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du_mas_1966_Lewellen.pdf |
application/pdf |
16.22MB |
0 |
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