Acoustic architecture of glaciolacustrine sediments deformed during zonal stagnation of the Laurentide Ice Sheet;
In North America, the last (Laurentide) Ice Sheet retreated from much of the Canadian Shield by ‘zonal stagnation’. Masses of dead ice, severed from the main ice sheet by emerging bedrock highs, downwasted in situ within valleys and lake basins and were commonly buried by sediment. Consequently, the...
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ftciteseerx:oai:CiteSeerX.psu:10.1.1.484.4335 2023-05-15T16:40:23+02:00 Acoustic architecture of glaciolacustrine sediments deformed during zonal stagnation of the Laurentide Ice Sheet; Nicholas Eyles A Mike Doughty A Joseph I. Boyce B Henry T. Mullins C The Pennsylvania State University CiteSeerX Archives 2001 application/pdf http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.484.4335 http://people.hws.edu/faculty/halfman/data/reprints/mazinawseismics.pdf en eng http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.484.4335 http://people.hws.edu/faculty/halfman/data/reprints/mazinawseismics.pdf Metadata may be used without restrictions as long as the oai identifier remains attached to it. http://people.hws.edu/faculty/halfman/data/reprints/mazinawseismics.pdf text 2001 ftciteseerx 2016-01-08T08:05:50Z In North America, the last (Laurentide) Ice Sheet retreated from much of the Canadian Shield by ‘zonal stagnation’. Masses of dead ice, severed from the main ice sheet by emerging bedrock highs, downwasted in situ within valleys and lake basins and were commonly buried by sediment. Consequently, the flat sediment floors of many valleys and lakes are now pitted by steep-sided, enclosed depressions (kettle basins) that record the melt of stagnant ice blocks and collapse of sediment. At Mazinaw Lake in eastern Ontario, Canada, high-resolution seismic reflection, magnetic and bathymetric surveys, integrated with onland outcrop and hammer seismic investigations, were conducted to identify the types of structural disturbance associated with the formation of kettle basins in glaciolacustrine sediments. Basins formed as a result of ice blocks being trapped within a regionally extensive proglacial lake (Glacial Lake Iroquois f 12,500 to 11,400 years BP) that flooded eastern Ontario during deglaciation. Kettles occur within a thick (>30 m) succession of parallel, high-frequency acoustic facies consisting of rhythmically laminated (varved?) Iroquois silty-clays. Iroquois strata underlying and surrounding kettle basins show large-scale normal faults, fractures, rotational failures and incoherent chaotically bedded sediment formed by slumping and collapse. Mazinaw Lake lies along part of the Ottawa Graben and while neotectonic earthquake activity cannot be entirely dismissed, deformation is most likely to have occurred as a result of the rapid melt of buried ice blocks. Seismic data do not fully penetrate the entire basin sediment fill but the structure and topography of bedrock can be inferred from magnetometer data. The location Text Ice Sheet Unknown Canada Glacial Lake ENVELOPE(-129.463,-129.463,58.259,58.259) |
institution |
Open Polar |
collection |
Unknown |
op_collection_id |
ftciteseerx |
language |
English |
description |
In North America, the last (Laurentide) Ice Sheet retreated from much of the Canadian Shield by ‘zonal stagnation’. Masses of dead ice, severed from the main ice sheet by emerging bedrock highs, downwasted in situ within valleys and lake basins and were commonly buried by sediment. Consequently, the flat sediment floors of many valleys and lakes are now pitted by steep-sided, enclosed depressions (kettle basins) that record the melt of stagnant ice blocks and collapse of sediment. At Mazinaw Lake in eastern Ontario, Canada, high-resolution seismic reflection, magnetic and bathymetric surveys, integrated with onland outcrop and hammer seismic investigations, were conducted to identify the types of structural disturbance associated with the formation of kettle basins in glaciolacustrine sediments. Basins formed as a result of ice blocks being trapped within a regionally extensive proglacial lake (Glacial Lake Iroquois f 12,500 to 11,400 years BP) that flooded eastern Ontario during deglaciation. Kettles occur within a thick (>30 m) succession of parallel, high-frequency acoustic facies consisting of rhythmically laminated (varved?) Iroquois silty-clays. Iroquois strata underlying and surrounding kettle basins show large-scale normal faults, fractures, rotational failures and incoherent chaotically bedded sediment formed by slumping and collapse. Mazinaw Lake lies along part of the Ottawa Graben and while neotectonic earthquake activity cannot be entirely dismissed, deformation is most likely to have occurred as a result of the rapid melt of buried ice blocks. Seismic data do not fully penetrate the entire basin sediment fill but the structure and topography of bedrock can be inferred from magnetometer data. The location |
author2 |
The Pennsylvania State University CiteSeerX Archives |
format |
Text |
author |
Nicholas Eyles A Mike Doughty A Joseph I. Boyce B Henry T. Mullins C |
spellingShingle |
Nicholas Eyles A Mike Doughty A Joseph I. Boyce B Henry T. Mullins C Acoustic architecture of glaciolacustrine sediments deformed during zonal stagnation of the Laurentide Ice Sheet; |
author_facet |
Nicholas Eyles A Mike Doughty A Joseph I. Boyce B Henry T. Mullins C |
author_sort |
Nicholas Eyles A |
title |
Acoustic architecture of glaciolacustrine sediments deformed during zonal stagnation of the Laurentide Ice Sheet; |
title_short |
Acoustic architecture of glaciolacustrine sediments deformed during zonal stagnation of the Laurentide Ice Sheet; |
title_full |
Acoustic architecture of glaciolacustrine sediments deformed during zonal stagnation of the Laurentide Ice Sheet; |
title_fullStr |
Acoustic architecture of glaciolacustrine sediments deformed during zonal stagnation of the Laurentide Ice Sheet; |
title_full_unstemmed |
Acoustic architecture of glaciolacustrine sediments deformed during zonal stagnation of the Laurentide Ice Sheet; |
title_sort |
acoustic architecture of glaciolacustrine sediments deformed during zonal stagnation of the laurentide ice sheet; |
publishDate |
2001 |
url |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.484.4335 http://people.hws.edu/faculty/halfman/data/reprints/mazinawseismics.pdf |
long_lat |
ENVELOPE(-129.463,-129.463,58.259,58.259) |
geographic |
Canada Glacial Lake |
geographic_facet |
Canada Glacial Lake |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_source |
http://people.hws.edu/faculty/halfman/data/reprints/mazinawseismics.pdf |
op_relation |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.484.4335 http://people.hws.edu/faculty/halfman/data/reprints/mazinawseismics.pdf |
op_rights |
Metadata may be used without restrictions as long as the oai identifier remains attached to it. |
_version_ |
1766030785325826048 |