Glaciotectonic deformation associated with the Orient Point–Fishers Island moraine, westernmost Block Island Sound : further evidence of readvance of the Laurentide ice sheet
This paper is not subject to U.S. copyright. The definitive version was published in Geo-Marine Letters 32 (2012): 279-288, doi:10.1007/s00367-012-0296-9. High-resolution seismic-reflection profiles collected across pro-glacial outwash deposits adjacent to the circa 18 ka b.p. Orient Point–Fishers I...
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ftwhoas:oai:darchive.mblwhoilibrary.org:1912/5355 2023-05-15T16:40:38+02:00 Glaciotectonic deformation associated with the Orient Point–Fishers Island moraine, westernmost Block Island Sound : further evidence of readvance of the Laurentide ice sheet Poppe, Lawrence J. Oldale, Robert N. Foster, David S. Smith, Shepard M. 2012-06-29 application/pdf https://hdl.handle.net/1912/5355 en_US eng Springer https://doi.org/10.1007/s00367-012-0296-9 Geo-Marine Letters 32 (2012): 279-288 https://hdl.handle.net/1912/5355 doi:10.1007/s00367-012-0296-9 Geo-Marine Letters 32 (2012): 279-288 doi:10.1007/s00367-012-0296-9 Article 2012 ftwhoas https://doi.org/10.1007/s00367-012-0296-9 2022-05-28T22:58:38Z This paper is not subject to U.S. copyright. The definitive version was published in Geo-Marine Letters 32 (2012): 279-288, doi:10.1007/s00367-012-0296-9. High-resolution seismic-reflection profiles collected across pro-glacial outwash deposits adjacent to the circa 18 ka b.p. Orient Point–Fishers Island end moraine segment in westernmost Block Island Sound reveal extensive deformation. A rhythmic seismic facies indicates the host outwash deposits are composed of fine-grained glaciolacustrine sediments. The deformation is variably brittle and ductile, but predominantly compressive in nature. Brittle deformation includes reverse faults and thrust faults that strike parallel to the moraine, and thrust sheets that extend from beneath the moraine. Ductile deformation includes folded sediments that overlie undisturbed deposits, showing that they are not drape features. Other seismic evidence for compression along the ice front consists of undisturbed glaciolacustrine strata that dip back toward and underneath the moraine, and angular unconformities on the sea floor where deformed sediments extend above the surrounding undisturbed correlative strata. Together, these ice-marginal glaciotectonic features indicate that the Orient Point–Fishers Island moraine marks a significant readvance of the Laurentide ice sheet, consistent with existing knowledge for neighboring coeval moraines, and not simply a stillstand as previously reported. This work was supported by the Connecticut Department of Environmental Protection, and the Atlantic Hydrographic Branch of the National Oceanic and Atmospheric Administration. 2013-06-29 Article in Journal/Newspaper Ice Sheet Woods Hole Scientific Community: WHOAS (Woods Hole Open Access Server) Block Island ENVELOPE(-62.347,-62.347,67.051,67.051) Fishers Island ENVELOPE(-108.119,-108.119,67.918,67.918) Orient Point ENVELOPE(177.702,177.702,51.950,51.950) Geo-Marine Letters 32 4 279 288 |
institution |
Open Polar |
collection |
Woods Hole Scientific Community: WHOAS (Woods Hole Open Access Server) |
op_collection_id |
ftwhoas |
language |
English |
description |
This paper is not subject to U.S. copyright. The definitive version was published in Geo-Marine Letters 32 (2012): 279-288, doi:10.1007/s00367-012-0296-9. High-resolution seismic-reflection profiles collected across pro-glacial outwash deposits adjacent to the circa 18 ka b.p. Orient Point–Fishers Island end moraine segment in westernmost Block Island Sound reveal extensive deformation. A rhythmic seismic facies indicates the host outwash deposits are composed of fine-grained glaciolacustrine sediments. The deformation is variably brittle and ductile, but predominantly compressive in nature. Brittle deformation includes reverse faults and thrust faults that strike parallel to the moraine, and thrust sheets that extend from beneath the moraine. Ductile deformation includes folded sediments that overlie undisturbed deposits, showing that they are not drape features. Other seismic evidence for compression along the ice front consists of undisturbed glaciolacustrine strata that dip back toward and underneath the moraine, and angular unconformities on the sea floor where deformed sediments extend above the surrounding undisturbed correlative strata. Together, these ice-marginal glaciotectonic features indicate that the Orient Point–Fishers Island moraine marks a significant readvance of the Laurentide ice sheet, consistent with existing knowledge for neighboring coeval moraines, and not simply a stillstand as previously reported. This work was supported by the Connecticut Department of Environmental Protection, and the Atlantic Hydrographic Branch of the National Oceanic and Atmospheric Administration. 2013-06-29 |
format |
Article in Journal/Newspaper |
author |
Poppe, Lawrence J. Oldale, Robert N. Foster, David S. Smith, Shepard M. |
spellingShingle |
Poppe, Lawrence J. Oldale, Robert N. Foster, David S. Smith, Shepard M. Glaciotectonic deformation associated with the Orient Point–Fishers Island moraine, westernmost Block Island Sound : further evidence of readvance of the Laurentide ice sheet |
author_facet |
Poppe, Lawrence J. Oldale, Robert N. Foster, David S. Smith, Shepard M. |
author_sort |
Poppe, Lawrence J. |
title |
Glaciotectonic deformation associated with the Orient Point–Fishers Island moraine, westernmost Block Island Sound : further evidence of readvance of the Laurentide ice sheet |
title_short |
Glaciotectonic deformation associated with the Orient Point–Fishers Island moraine, westernmost Block Island Sound : further evidence of readvance of the Laurentide ice sheet |
title_full |
Glaciotectonic deformation associated with the Orient Point–Fishers Island moraine, westernmost Block Island Sound : further evidence of readvance of the Laurentide ice sheet |
title_fullStr |
Glaciotectonic deformation associated with the Orient Point–Fishers Island moraine, westernmost Block Island Sound : further evidence of readvance of the Laurentide ice sheet |
title_full_unstemmed |
Glaciotectonic deformation associated with the Orient Point–Fishers Island moraine, westernmost Block Island Sound : further evidence of readvance of the Laurentide ice sheet |
title_sort |
glaciotectonic deformation associated with the orient point–fishers island moraine, westernmost block island sound : further evidence of readvance of the laurentide ice sheet |
publisher |
Springer |
publishDate |
2012 |
url |
https://hdl.handle.net/1912/5355 |
long_lat |
ENVELOPE(-62.347,-62.347,67.051,67.051) ENVELOPE(-108.119,-108.119,67.918,67.918) ENVELOPE(177.702,177.702,51.950,51.950) |
geographic |
Block Island Fishers Island Orient Point |
geographic_facet |
Block Island Fishers Island Orient Point |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_source |
Geo-Marine Letters 32 (2012): 279-288 doi:10.1007/s00367-012-0296-9 |
op_relation |
https://doi.org/10.1007/s00367-012-0296-9 Geo-Marine Letters 32 (2012): 279-288 https://hdl.handle.net/1912/5355 doi:10.1007/s00367-012-0296-9 |
op_doi |
https://doi.org/10.1007/s00367-012-0296-9 |
container_title |
Geo-Marine Letters |
container_volume |
32 |
container_issue |
4 |
container_start_page |
279 |
op_container_end_page |
288 |
_version_ |
1766031046617333760 |