Melt Regimes, Internal Stratigraphy, and Flow Dynamics of Three Glaciers in the Alaska Range
Mountain and alpine valley glaciers are often described by their thermal characteristics, which, in turn, are heavily influenced by environmental factors such as latitude and elevation, amongst others. Low elevation and/or low latitude glaciers that experience melting throughout the snow pack are in...
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ftmaineuniv:oai:digitalcommons.library.umaine.edu:etd-1771 2023-06-11T04:03:08+02:00 Melt Regimes, Internal Stratigraphy, and Flow Dynamics of Three Glaciers in the Alaska Range Campbell, Seth William 2010-01-01T08:00:00Z application/pdf https://digitalcommons.library.umaine.edu/etd/773 https://digitalcommons.library.umaine.edu/context/etd/article/1771/viewcontent/CampbellSW2010.pdf unknown DigitalCommons@UMaine https://digitalcommons.library.umaine.edu/etd/773 https://digitalcommons.library.umaine.edu/context/etd/article/1771/viewcontent/CampbellSW2010.pdf Electronic Theses and Dissertations Glaciology Melt Regimes Internal Stratigraphy Earth Sciences text 2010 ftmaineuniv 2023-05-04T18:00:37Z Mountain and alpine valley glaciers are often described by their thermal characteristics, which, in turn, are heavily influenced by environmental factors such as latitude and elevation, amongst others. Low elevation and/or low latitude glaciers that experience melting throughout the snow pack are in the wet zone. Whereas glaciers at higher elevations and/or higher latitudes that experience some melting and refreezing, or no melting, are in the percolation and dry zones, respectively. Defining boundary elevations between these melt regimes is a fundamental step to determine where melting occurs, both locally (glacier scale) and regionally (mountain range scale). Secondly, ice cores, a primary source of paleoclimate information, require glacier ice which has experienced minimal melting and deformation. Herein, I use ground penetrating radar (GPR), geodetic, and glaciochemical evidence collected on three glaciers from the Alaska Range, to estimate regional melt regime boundary elevations. I simultaneously use the same evidence to assess englacial stratigraphy and flow dynamics of the three glaciers and make recommendations for potential ice core drill sites based on pre-determined drilling criteria. Glaciochemical and snow pit stratigraphy collected at Kahiltna Pass Basin on Mount McKinley (3100 masl) show evidence of some melt and refreezing in the snow pack and firn suggesting this site is in the upper region of the percolation zone. Radar profiles and surface velocity data show a maximum depth of 300 meters in the basin and westward dipping englacial stratigraphy that experienced vertical thickening as it flowed from a steep, narrow, and high velocity valley into a flat, wide basin in which velocities were slower. Stratigraphy on the western side of this basin is surface conformable, but likely experiences some fanning and thinning due to the increasing basin dimensions relative to the narrow valley, up-glacier. Radar profiles show that isochronal integrity is preserved and mostly continuous within the upper ... Text alaska range glacier glaciers ice core Alaska The University of Maine: DigitalCommons@UMaine Fanning ENVELOPE(-60.632,-60.632,-72.404,-72.404) |
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Open Polar |
collection |
The University of Maine: DigitalCommons@UMaine |
op_collection_id |
ftmaineuniv |
language |
unknown |
topic |
Glaciology Melt Regimes Internal Stratigraphy Earth Sciences |
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Glaciology Melt Regimes Internal Stratigraphy Earth Sciences Campbell, Seth William Melt Regimes, Internal Stratigraphy, and Flow Dynamics of Three Glaciers in the Alaska Range |
topic_facet |
Glaciology Melt Regimes Internal Stratigraphy Earth Sciences |
description |
Mountain and alpine valley glaciers are often described by their thermal characteristics, which, in turn, are heavily influenced by environmental factors such as latitude and elevation, amongst others. Low elevation and/or low latitude glaciers that experience melting throughout the snow pack are in the wet zone. Whereas glaciers at higher elevations and/or higher latitudes that experience some melting and refreezing, or no melting, are in the percolation and dry zones, respectively. Defining boundary elevations between these melt regimes is a fundamental step to determine where melting occurs, both locally (glacier scale) and regionally (mountain range scale). Secondly, ice cores, a primary source of paleoclimate information, require glacier ice which has experienced minimal melting and deformation. Herein, I use ground penetrating radar (GPR), geodetic, and glaciochemical evidence collected on three glaciers from the Alaska Range, to estimate regional melt regime boundary elevations. I simultaneously use the same evidence to assess englacial stratigraphy and flow dynamics of the three glaciers and make recommendations for potential ice core drill sites based on pre-determined drilling criteria. Glaciochemical and snow pit stratigraphy collected at Kahiltna Pass Basin on Mount McKinley (3100 masl) show evidence of some melt and refreezing in the snow pack and firn suggesting this site is in the upper region of the percolation zone. Radar profiles and surface velocity data show a maximum depth of 300 meters in the basin and westward dipping englacial stratigraphy that experienced vertical thickening as it flowed from a steep, narrow, and high velocity valley into a flat, wide basin in which velocities were slower. Stratigraphy on the western side of this basin is surface conformable, but likely experiences some fanning and thinning due to the increasing basin dimensions relative to the narrow valley, up-glacier. Radar profiles show that isochronal integrity is preserved and mostly continuous within the upper ... |
format |
Text |
author |
Campbell, Seth William |
author_facet |
Campbell, Seth William |
author_sort |
Campbell, Seth William |
title |
Melt Regimes, Internal Stratigraphy, and Flow Dynamics of Three Glaciers in the Alaska Range |
title_short |
Melt Regimes, Internal Stratigraphy, and Flow Dynamics of Three Glaciers in the Alaska Range |
title_full |
Melt Regimes, Internal Stratigraphy, and Flow Dynamics of Three Glaciers in the Alaska Range |
title_fullStr |
Melt Regimes, Internal Stratigraphy, and Flow Dynamics of Three Glaciers in the Alaska Range |
title_full_unstemmed |
Melt Regimes, Internal Stratigraphy, and Flow Dynamics of Three Glaciers in the Alaska Range |
title_sort |
melt regimes, internal stratigraphy, and flow dynamics of three glaciers in the alaska range |
publisher |
DigitalCommons@UMaine |
publishDate |
2010 |
url |
https://digitalcommons.library.umaine.edu/etd/773 https://digitalcommons.library.umaine.edu/context/etd/article/1771/viewcontent/CampbellSW2010.pdf |
long_lat |
ENVELOPE(-60.632,-60.632,-72.404,-72.404) |
geographic |
Fanning |
geographic_facet |
Fanning |
genre |
alaska range glacier glaciers ice core Alaska |
genre_facet |
alaska range glacier glaciers ice core Alaska |
op_source |
Electronic Theses and Dissertations |
op_relation |
https://digitalcommons.library.umaine.edu/etd/773 https://digitalcommons.library.umaine.edu/context/etd/article/1771/viewcontent/CampbellSW2010.pdf |
_version_ |
1768377301322432512 |