St Andrews Research Repository

St Andrews University Home
View Item 
  •   St Andrews Research Repository
  • University of St Andrews Research
  • University of St Andrews Research
  • University of St Andrews Research
  • View Item
  •   St Andrews Research Repository
  • University of St Andrews Research
  • University of St Andrews Research
  • University of St Andrews Research
  • View Item
  •   St Andrews Research Repository
  • University of St Andrews Research
  • University of St Andrews Research
  • University of St Andrews Research
  • View Item
  • Login
JavaScript is disabled for your browser. Some features of this site may not work without it.

Internal dynamics condition centennial-scale oscillations in marinebased ice-stream retreat

Thumbnail
View/Open
Ballantyne_2017_Geology_Ice_streamRetreat_CC.pdf (705.0Kb)
Date
07/2017
Author
Smedley, R. K.
Chiverrell, R. C.
Ballantyne, C. K.
Burke, M. J.
Clark, C. D.
Duller, G. A. T.
Fabel, D.
McCarroll, D.
Scourse, J. D.
Small, D.
Thomas, G. S. P.
Keywords
QE Geology
Geology
DAS
Metadata
Show full item record
Altmetrics Handle Statistics
Altmetrics DOI Statistics
Abstract
Rates of ice-stream retreat over decades can be determined from repeated satellite surveys and over millennia by paleoenvironmental reconstructions. Centennial time scales are an important temporal gap in geological observations of value in process understanding and evaluation of numerical models. We address this temporal gap by developing a 3 ka and 123 km retreat time series for the Irish Sea ice stream (ISIS), a major outlet draining the last British-Irish ice sheet. The Llŷn Peninsula (northwest Wales, UK) contains numerous ice-marginal indicators from which we reconstructed a robust chronological framework of margin oscillations. The landscape documents the retreat of a former marine-terminating ice stream through a topographic constriction, across a reverse bed slope, and across variations in calving margin width. New dating constraints for this sequence were integrated in a Bayesian sequence model to develop a high-resolution ice-retreat chronology. Our results show that retreat of the ISIS during the period 24-20 ka displayed centennial-scale oscillatory behavior of the margin despite relatively stable climatic, oceanic, and relative sea-level forcing mechanisms. Faster retreat rates coincided with greater axial trough depths as the ice passed over a reverse bed slope and the calving margin widened (from 65 to 139 km). The geological observations presented here over a 123-km-long ice-retreat sequence are consistent with theory that marine-based ice can be inherently unstable when passing over a reverse bed slope, but also that wider calving margins lead to much faster ice retreat.
Citation
Smedley , R K , Chiverrell , R C , Ballantyne , C K , Burke , M J , Clark , C D , Duller , G A T , Fabel , D , McCarroll , D , Scourse , J D , Small , D & Thomas , G S P 2017 , ' Internal dynamics condition centennial-scale oscillations in marinebased ice-stream retreat ' , Geology , vol. 45 , no. 9 , pp. 787-790 . https://doi.org/10.1130/G38991.1
Publication
Geology
Status
Peer reviewed
DOI
https://doi.org/10.1130/G38991.1
ISSN
0091-7613
Type
Journal article
Rights
© 2017 The Authors. Gold Open Access: This paper is published under the terms of the CC-BY license.
Description
This paper was supported by a Natural Environment Research Council consortium grant (BRITICECHRONO NE/J008672/1).
Collections
  • University of St Andrews Research
URI
http://hdl.handle.net/10023/11672

Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.

Advanced Search

Browse

All of RepositoryCommunities & CollectionsBy Issue DateNamesTitlesSubjectsClassificationTypeFunderThis CollectionBy Issue DateNamesTitlesSubjectsClassificationTypeFunder

My Account

Login

Open Access

To find out how you can benefit from open access to research, see our library web pages and Open Access blog. For open access help contact: openaccess@st-andrews.ac.uk.

Accessibility

Read our Accessibility statement.

How to submit research papers

The full text of research papers can be submitted to the repository via Pure, the University's research information system. For help see our guide: How to deposit in Pure.

Electronic thesis deposit

Help with deposit.

Repository help

For repository help contact: Digital-Repository@st-andrews.ac.uk.

Give Feedback

Cookie policy

This site may use cookies. Please see Terms and Conditions.

Usage statistics

COUNTER-compliant statistics on downloads from the repository are available from the IRUS-UK Service. Contact us for information.

© University of St Andrews Library

University of St Andrews is a charity registered in Scotland, No SC013532.

  • Facebook
  • Twitter