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Rapid subglacial streamlined bedform formation at a calving bay margin

Dowling, Thomas LU ; Möller, Per LU and Spagnolo, Matteo (2016) In Journal of Quaternary Science 31(8). p.879-892
Abstract
Using the LiDAR-derived Swedish national height model we have identified previously undescribed shallow streamlined glacial bedforms, small-scale drumlins, on the Närke plain in south-central Sweden. These drumlins could only be detected with high-resolution LiDAR, due to both their subtle size and forest cover. In this area the ice margin receded in a subaqueous environment with a proglacial water depth in the order of 100 m during the last deglaciation. As indicated by the configuration of marginally formed De Geer moraine ridges draping the drumlinoids, the receding ice margin formed deeply indented calving bays. These were located around subaqueous outlets of the subglacial melt-water drainage, with their apex position marked... (More)
Using the LiDAR-derived Swedish national height model we have identified previously undescribed shallow streamlined glacial bedforms, small-scale drumlins, on the Närke plain in south-central Sweden. These drumlins could only be detected with high-resolution LiDAR, due to both their subtle size and forest cover. In this area the ice margin receded in a subaqueous environment with a proglacial water depth in the order of 100 m during the last deglaciation. As indicated by the configuration of marginally formed De Geer moraine ridges draping the drumlinoids, the receding ice margin formed deeply indented calving bays. These were located around subaqueous outlets of the subglacial melt-water drainage, with their apex position marked geomorphologically by beaded esker ridges. The mapped small-scale drumlins are aligned perpendicular to the reconstructed ice sheet margin and suggest formation along flow lines adjusted to the configuration of these calving embayments as they propagated up-flow with ice margin retreat. Based on these geometric relationships we argue that the emplacement of the drumlins was near-marginal, ∼7.7–1 km from the margin, on a short timescale (∼5–35 years). (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Journal of Quaternary Science
volume
31
issue
8
pages
14 pages
publisher
John Wiley & Sons
external identifiers
  • scopus:85006269735
  • wos:000390345600005
ISSN
1099-1417
DOI
10.1002/jqs.2912
language
English
LU publication?
yes
id
2249cf6a-7820-40d8-b5a5-ba2f26bc86bd
date added to LUP
2016-12-28 11:12:24
date last changed
2017-09-18 11:33:37
@article{2249cf6a-7820-40d8-b5a5-ba2f26bc86bd,
  abstract     = {Using the LiDAR-derived Swedish national height model we have identified previously undescribed shallow streamlined glacial bedforms, small-scale drumlins, on the Närke plain in south-central Sweden. These drumlins could only be detected with high-resolution LiDAR, due to both their subtle size and forest cover. In this area the ice margin receded in a subaqueous environment with a proglacial water depth in the order of 100 m during the last deglaciation. As indicated by the configuration of marginally formed De Geer moraine ridges draping the drumlinoids, the receding ice margin formed deeply indented calving bays. These were located around subaqueous outlets of the subglacial melt-water drainage, with their apex position marked geomorphologically by beaded esker ridges. The mapped small-scale drumlins are aligned perpendicular to the reconstructed ice sheet margin and suggest formation along flow lines adjusted to the configuration of these calving embayments as they propagated up-flow with ice margin retreat. Based on these geometric relationships we argue that the emplacement of the drumlins was near-marginal, ∼7.7–1 km from the margin, on a short timescale (∼5–35 years).},
  author       = {Dowling, Thomas and Möller, Per and Spagnolo, Matteo},
  issn         = {1099-1417},
  language     = {eng},
  month        = {12},
  number       = {8},
  pages        = {879--892},
  publisher    = {John Wiley & Sons},
  series       = {Journal of Quaternary Science},
  title        = {Rapid subglacial streamlined bedform formation at a calving bay margin},
  url          = {http://dx.doi.org/10.1002/jqs.2912},
  volume       = {31},
  year         = {2016},
}