The University of Southampton
University of Southampton Institutional Repository

Paired 26Al and 10Be exposure ages from Lundy: new evidence for the extent and timing of Devensian glaciation in the southern British Isles

Paired 26Al and 10Be exposure ages from Lundy: new evidence for the extent and timing of Devensian glaciation in the southern British Isles
Paired 26Al and 10Be exposure ages from Lundy: new evidence for the extent and timing of Devensian glaciation in the southern British Isles
Lundy lies in a strategic geographical position for understanding the glacial history of the British Isles.
The island bears evidence of glaciation, largely in the form of ice-moulded bedrock and glaciallytransported
boulders e an unusual occurrence this far south in the British Isles. Irish Sea ice penetrated
the western Bristol Channel overriding Lundy from the northwest during the last phase of
glaciation in this area. The results of paired terrestrial cosmogenic nuclide analyses (26Al/10Be) constrain
the timing of this extensive glaciation and provide, for the first time, an age for the exposure of Lundy
granite following deglaciation. The results from nine paired samples yield 26Al/10Be exposure ages of
31.4e48.8 ka (10Be) and 31.7e60.0 ka (26Al). This challenges the view that any glaciation this far south
must belong to Middle Pleistocene glaciations, such as the Anglian Stage (c. 480e420 ka) and
a Devensian age for the last glaciation is consistent with findings from the Isles of Scilly further south.
However, the findings suggest early-mid Devensian (marine isotope stage (MIS) 4e3) glaciation of
Lundy. It also implies that the island was exposed or covered for a short time by non-erosive cold-based
ice at the global Last Glacial Maximum (LGM) during MIS 2 (26e21 ka). The potential exposure of the
island throughout MIS 2 contrasts with the evidence from the Isles of Scilly and the Celtic Sea, which
were glaciated at the LGM.
0277-3791
61-73
Rolfe, C.J.
b87801d1-90d2-41f1-85b8-fec405fe5557
Hughes, P.
5bd3dd2d-388a-42af-b26b-3b6915ae563d
Fenton, C.R.
d3056843-78ee-414c-8f67-468cb64b21cc
Xu, S.
cc1b53e4-d014-4d72-9af3-073ea273e88f
Brown, A.G.
c51f9d3e-02b0-47da-a483-41c354e78fab
Rolfe, C.J.
b87801d1-90d2-41f1-85b8-fec405fe5557
Hughes, P.
5bd3dd2d-388a-42af-b26b-3b6915ae563d
Fenton, C.R.
d3056843-78ee-414c-8f67-468cb64b21cc
Xu, S.
cc1b53e4-d014-4d72-9af3-073ea273e88f
Brown, A.G.
c51f9d3e-02b0-47da-a483-41c354e78fab

Rolfe, C.J., Hughes, P., Fenton, C.R., Xu, S. and Brown, A.G. (2012) Paired 26Al and 10Be exposure ages from Lundy: new evidence for the extent and timing of Devensian glaciation in the southern British Isles. Quaternary Science Reviews, 43, 61-73. (doi:10.1016/j.quascirev.2012.04.003).

Record type: Article

Abstract

Lundy lies in a strategic geographical position for understanding the glacial history of the British Isles.
The island bears evidence of glaciation, largely in the form of ice-moulded bedrock and glaciallytransported
boulders e an unusual occurrence this far south in the British Isles. Irish Sea ice penetrated
the western Bristol Channel overriding Lundy from the northwest during the last phase of
glaciation in this area. The results of paired terrestrial cosmogenic nuclide analyses (26Al/10Be) constrain
the timing of this extensive glaciation and provide, for the first time, an age for the exposure of Lundy
granite following deglaciation. The results from nine paired samples yield 26Al/10Be exposure ages of
31.4e48.8 ka (10Be) and 31.7e60.0 ka (26Al). This challenges the view that any glaciation this far south
must belong to Middle Pleistocene glaciations, such as the Anglian Stage (c. 480e420 ka) and
a Devensian age for the last glaciation is consistent with findings from the Isles of Scilly further south.
However, the findings suggest early-mid Devensian (marine isotope stage (MIS) 4e3) glaciation of
Lundy. It also implies that the island was exposed or covered for a short time by non-erosive cold-based
ice at the global Last Glacial Maximum (LGM) during MIS 2 (26e21 ka). The potential exposure of the
island throughout MIS 2 contrasts with the evidence from the Isles of Scilly and the Celtic Sea, which
were glaciated at the LGM.

Text
Rolf_et_al_2012.pdf - Version of Record
Restricted to Repository staff only
Request a copy

More information

e-pub ahead of print date: 9 May 2012
Published date: 8 June 2012
Organisations: Palaeoenvironment Laboratory (PLUS)

Identifiers

Local EPrints ID: 338387
URI: http://eprints.soton.ac.uk/id/eprint/338387
ISSN: 0277-3791
PURE UUID: a11d5bf7-eb40-4036-8ac9-60ed3e744488
ORCID for A.G. Brown: ORCID iD orcid.org/0000-0002-1990-4654

Catalogue record

Date deposited: 16 May 2012 10:48
Last modified: 15 Mar 2024 03:27

Export record

Altmetrics

Contributors

Author: C.J. Rolfe
Author: P. Hughes
Author: C.R. Fenton
Author: S. Xu
Author: A.G. Brown ORCID iD

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×