Refining the span and rates of deposition of the Glenwood phase of Lake Chicago
The Glenwood phase of proglacial Lake Chicago is its oldest phase, but is the least studied. By developing the and ideas previously published maps by Bretz in the 1930s and studies by Hansel, Mickelson, Thompson and others I will be redefining the span and role of the Glenwood Phase of proglacial La...
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ftunivillidea:oai:www.ideals.illinois.edu:2142/92666 2024-10-20T14:09:30+00:00 Refining the span and rates of deposition of the Glenwood phase of Lake Chicago Bruegger, Alison Rae Conroy, Jessica Curry, B. Brandon 2016-08 application/pdf http://hdl.handle.net/2142/92666 en eng http://hdl.handle.net/2142/92666 Copyright 2016 Alison Bruegger Lake Chicago Glenwood Illinois text 2016 ftunivillidea 2024-10-01T12:57:50Z The Glenwood phase of proglacial Lake Chicago is its oldest phase, but is the least studied. By developing the and ideas previously published maps by Bretz in the 1930s and studies by Hansel, Mickelson, Thompson and others I will be redefining the span and role of the Glenwood Phase of proglacial Lake Chicago. This task will be completed by using LiDAR DEMs and by obtaining sediment cores proximal to Glenwood phase features and using age models created by AMS C-14 ages. Using this information, in addition to grain size analyses and clay mineral analyses, I will determine the span of the Glenwood phase of Glacial Lake Chicago and indirectly determine the timing of any large meltwater floods and the rate of downcutting of the Chicago Outlet during the transition from the Glenwood phase to its successive Calumet phase. 22 new radiocarbon ages of needles, charcoal and plant marcrofossils were obtained from cores sampled near Glenwood phase features that can still be easily identified. The age models created from the new ages indicate a disturbance in the record at about 15.1 ka. Presently, it is yet debated if the drop from the Glenwood to the Calumet level was due to gradual changes in hydrology or to rapid incision of the Chicago Outlet. If the sediment accumulation rate abruptly decreases simultaneously with the end of the Glenwood phase and subsequently the ~7meter drop from the Glenwood to the Calumet lake levels, that reflects sudden erosion of the Chicago Outlet. The produced age models do present evidence for an abrupt incision near the end of the Glenwood, but a more in depth look at LiDAR evidence proves the Glenwood/Calumet transition to be a bit more complex. A revised history of the Glenwood Phase of Glacial Lake Chicago will help resolve issues of the nature of downstream contributions of Glacial Lake Chicago to the Illinois and Mississippi Rivers, and Gulf of Mexico as well as upstream contributions from the Laurentide Ice Sheet into Glacial Lake Chicago. Submission original under an indefinite ... Text Ice Sheet University of Illinois at Urbana-Champaign: IDEALS (Illinois Digital Environment for Access to Learning and Scholarship) Glacial Lake ENVELOPE(-129.463,-129.463,58.259,58.259) Calumet ENVELOPE(-135.389,-135.389,63.927,63.927) Calumet Lake ENVELOPE(-111.766,-111.766,57.417,57.417) |
institution |
Open Polar |
collection |
University of Illinois at Urbana-Champaign: IDEALS (Illinois Digital Environment for Access to Learning and Scholarship) |
op_collection_id |
ftunivillidea |
language |
English |
topic |
Lake Chicago Glenwood Illinois |
spellingShingle |
Lake Chicago Glenwood Illinois Bruegger, Alison Rae Refining the span and rates of deposition of the Glenwood phase of Lake Chicago |
topic_facet |
Lake Chicago Glenwood Illinois |
description |
The Glenwood phase of proglacial Lake Chicago is its oldest phase, but is the least studied. By developing the and ideas previously published maps by Bretz in the 1930s and studies by Hansel, Mickelson, Thompson and others I will be redefining the span and role of the Glenwood Phase of proglacial Lake Chicago. This task will be completed by using LiDAR DEMs and by obtaining sediment cores proximal to Glenwood phase features and using age models created by AMS C-14 ages. Using this information, in addition to grain size analyses and clay mineral analyses, I will determine the span of the Glenwood phase of Glacial Lake Chicago and indirectly determine the timing of any large meltwater floods and the rate of downcutting of the Chicago Outlet during the transition from the Glenwood phase to its successive Calumet phase. 22 new radiocarbon ages of needles, charcoal and plant marcrofossils were obtained from cores sampled near Glenwood phase features that can still be easily identified. The age models created from the new ages indicate a disturbance in the record at about 15.1 ka. Presently, it is yet debated if the drop from the Glenwood to the Calumet level was due to gradual changes in hydrology or to rapid incision of the Chicago Outlet. If the sediment accumulation rate abruptly decreases simultaneously with the end of the Glenwood phase and subsequently the ~7meter drop from the Glenwood to the Calumet lake levels, that reflects sudden erosion of the Chicago Outlet. The produced age models do present evidence for an abrupt incision near the end of the Glenwood, but a more in depth look at LiDAR evidence proves the Glenwood/Calumet transition to be a bit more complex. A revised history of the Glenwood Phase of Glacial Lake Chicago will help resolve issues of the nature of downstream contributions of Glacial Lake Chicago to the Illinois and Mississippi Rivers, and Gulf of Mexico as well as upstream contributions from the Laurentide Ice Sheet into Glacial Lake Chicago. Submission original under an indefinite ... |
author2 |
Conroy, Jessica Curry, B. Brandon |
format |
Text |
author |
Bruegger, Alison Rae |
author_facet |
Bruegger, Alison Rae |
author_sort |
Bruegger, Alison Rae |
title |
Refining the span and rates of deposition of the Glenwood phase of Lake Chicago |
title_short |
Refining the span and rates of deposition of the Glenwood phase of Lake Chicago |
title_full |
Refining the span and rates of deposition of the Glenwood phase of Lake Chicago |
title_fullStr |
Refining the span and rates of deposition of the Glenwood phase of Lake Chicago |
title_full_unstemmed |
Refining the span and rates of deposition of the Glenwood phase of Lake Chicago |
title_sort |
refining the span and rates of deposition of the glenwood phase of lake chicago |
publishDate |
2016 |
url |
http://hdl.handle.net/2142/92666 |
long_lat |
ENVELOPE(-129.463,-129.463,58.259,58.259) ENVELOPE(-135.389,-135.389,63.927,63.927) ENVELOPE(-111.766,-111.766,57.417,57.417) |
geographic |
Glacial Lake Calumet Calumet Lake |
geographic_facet |
Glacial Lake Calumet Calumet Lake |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_relation |
http://hdl.handle.net/2142/92666 |
op_rights |
Copyright 2016 Alison Bruegger |
_version_ |
1813449035569168384 |