Marginal formation of De Geer moraines and their implications to the dynamics of grounding-line recession
Lindén, Mattias LU and Möller, Per LU
(2005)
In Journal of Quaternary Science
20(2).
p.113-133
- Abstract
- De Geer moraine ridges occur in abundance in the coastal zone of northern Sweden, preferentially in areas with proglacial water depths in excess of 150 m at deglaciation. From detailed sedimentological and structural investigations in machine-dug trenches across De Geer ridges it is concluded that the moraines formed due to subglacial sediment advection to the ice margin during temporary halts in grounding-line retreat, forming gradually thickening sediment wedges. The proximal part of the moraines were built up in submarginal position as stacked sequences of deforming bed diamictons, intercalated with glaciofluvial canal-infill sediments, whereas the distal parts were built up from the grounding line by prograding sediment gravity-flow... (More)
- De Geer moraine ridges occur in abundance in the coastal zone of northern Sweden, preferentially in areas with proglacial water depths in excess of 150 m at deglaciation. From detailed sedimentological and structural investigations in machine-dug trenches across De Geer ridges it is concluded that the moraines formed due to subglacial sediment advection to the ice margin during temporary halts in grounding-line retreat, forming gradually thickening sediment wedges. The proximal part of the moraines were built up in submarginal position as stacked sequences of deforming bed diamictons, intercalated with glaciofluvial canal-infill sediments, whereas the distal parts were built up from the grounding line by prograding sediment gravity-flow deposits, distally interfingering with glaciolacustrine sediments. The rapid grounding-line retreat (ca. 400 m yr(-1)) was driven by rapid calving, in turn enhanced by fast iceflow and marginal thinning of ice due to deforming bed conditions. The spatial distribution of the moraine ridges indicates stepwise retreat of the grounding line. It is suggested that this is due to slab and flake calving of the ice cliff above the waterline, forming a gradually widening subaqueous ice ledge which eventually breaks off to a new grounding line, followed by regained sediment delivery and ridge build-up. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/249906
- author
- Lindén, Mattias
LU
and Möller, Per
LU
- organization
- publishing date
- 2005
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- deforming bed, subaqueous deglaciation, De Geer moraines, glacial sedimentology, grounding line
- in
- Journal of Quaternary Science
- volume
- 20
- issue
- 2
- pages
- 113 - 133
- publisher
- John Wiley & Sons Inc.
- external identifiers
-
- wos:000227618100002
- scopus:14944354025
- ISSN
- 1099-1417
- DOI
- 10.1002/jqs.902
- language
- English
- LU publication?
- yes
- id
- cac1de06-781e-4007-a48f-a511f588419a (old id 249906)
- date added to LUP
- 2016-04-01 15:46:34
- date last changed
- 2022-04-14 23:51:03
@article{cac1de06-781e-4007-a48f-a511f588419a,
abstract = {{De Geer moraine ridges occur in abundance in the coastal zone of northern Sweden, preferentially in areas with proglacial water depths in excess of 150 m at deglaciation. From detailed sedimentological and structural investigations in machine-dug trenches across De Geer ridges it is concluded that the moraines formed due to subglacial sediment advection to the ice margin during temporary halts in grounding-line retreat, forming gradually thickening sediment wedges. The proximal part of the moraines were built up in submarginal position as stacked sequences of deforming bed diamictons, intercalated with glaciofluvial canal-infill sediments, whereas the distal parts were built up from the grounding line by prograding sediment gravity-flow deposits, distally interfingering with glaciolacustrine sediments. The rapid grounding-line retreat (ca. 400 m yr(-1)) was driven by rapid calving, in turn enhanced by fast iceflow and marginal thinning of ice due to deforming bed conditions. The spatial distribution of the moraine ridges indicates stepwise retreat of the grounding line. It is suggested that this is due to slab and flake calving of the ice cliff above the waterline, forming a gradually widening subaqueous ice ledge which eventually breaks off to a new grounding line, followed by regained sediment delivery and ridge build-up.}},
author = {{Lindén, Mattias and Möller, Per}},
issn = {{1099-1417}},
keywords = {{deforming bed; subaqueous deglaciation; De Geer moraines; glacial sedimentology; grounding line}},
language = {{eng}},
number = {{2}},
pages = {{113--133}},
publisher = {{John Wiley & Sons Inc.}},
series = {{Journal of Quaternary Science}},
title = {{Marginal formation of De Geer moraines and their implications to the dynamics of grounding-line recession}},
url = {{http://dx.doi.org/10.1002/jqs.902}},
doi = {{10.1002/jqs.902}},
volume = {{20}},
year = {{2005}},
}