FN Archimer Export Format
PT J
TI Cosmogenic exposure age constraints on deglaciation and flow behaviour of a marine-based ice stream in western Scotland, 21-16 ka
BT 
AF SMALL, David
   BENETTI, Sara
   DOVE, Dayton
   BALLANTYNE, Colin K.
   FABEL, Derek
   CLARK, Chris D.
   GHEORGHIU, Delia M.
   NEWALL, Jennifer
   XU, Sheng
AS 1:1;2:2;3:3;4:4;5:5;6:6;7:7;8:1;9:5;
FF 1:;2:;3:;4:;5:;6:;7:;8:;9:;
C1 Univ Glasgow, Dept Geog & Earth Sci, Glasgow G12 8QQ, Lanark, Scotland.
   Univ Ulster, Sch Environm Sci, Coleraine BT52 1SA, Londonderry, North Ireland.
   Lyell Ctr, British Geol Survey, Edinburgh EH14 4AP, Midlothian, Scotland.
   Univ St Andrews, Sch Geog & Sustainable Dev, St Andrews KY16 9AL, Fife, Scotland.
   Scottish Univ Environm Res Ctr, SUERC AMS Lab, E Kilbride G75 0QF, Lanark, Scotland.
   Univ Sheffield, Dept Geog, Sheffield S10 2TN, S Yorkshire, England.
   SUERC, NERC Cosmogen Isotope Anal Facil, E Kilbride G75 0QF, Lanark, Scotland.
C2 UNIV GLASGOW, SCOTLAND
   UNIV ULSTER, NORTH IRELAND
   BRITISH GEOL SURVEY, SCOTLAND
   UNIV ST ANDREWS, SCOTLAND
   SUERC, SCOTLAND
   UNIV SHEFFIELD, ENGLAND
   NERC, SCOTLAND
IF 4.334
TC 29
UR https://archimer.ifremer.fr/doc/00420/53148/55337.pdf
LA English
DT Article
CR IMAGES 1-MD101
BO Marion Dufresne
DE ;Exposure dating;Marine ice stream;British-Irish ice sheet;Deglaciation
AB Understanding how marine-based ice streams operated during episodes of deglaciation requires geochronological data that constrain both timing of deglaciation and changes in their flow behaviour, such as that from unconstrained ice streaming to topographically restricted flow. We present seventeen new Be-10 exposure ages from glacial boulders and bedrock at sites in western Scotland within the area drained by the Hebrides Ice Stream, a marine-based ice stream that drained a large proportion of the former British-Irish Ice Sheet. Exposure ages from Tiree constrain deglaciation of a topographic high within the central zone of the ice stream, from which convergent flowsets were produced during ice streaming. These ages thus constrain thinning of the Hebrides Ice Stream, which, on the basis of supporting information, we infer to represent cessation of ice streaming at 20.6 +/- 1.2 ka, 3-4 ka earlier than previously inferred. A period of more topographically restricted flow produced flow indicators superimposed on those relating to full ice stream conditions, and exposure ages from up-stream of these constrain deglaciation to 17.5 +/- 1.0 ka. Complete deglaciation of the marine sector of the Hebrides Ice Stream occurred by 17-16 ka at which time the ice margin was located near the present coastline. Exposure ages from the southernmost Outer Hebrides (Mingulay and Barra) indicate deglaciation at 18.9 +/- 1.0 and 17.1 +/- 1.0 ka respectively, demonstrating that an independent ice cap persisted on the southern Outer Hebrides for 3-4 ka after initial ice stream deglaciation. This suggests that deglaciation of the Hebrides Ice Stream was focused along major submarine troughs. Collectively, our data constrain initial deglaciation and changes in flow regime of the Hebrides Ice Stream, final deglaciation of its marine sector, and deglaciation of the southern portion of the independent Outer Hebrides Ice Cap, providing chronological constraints on future numerical reconstructions of this key sector of the former British Irish Ice Sheet. 
PY 2017
PD JUN
SO Quaternary Science Reviews
SN 0277-3791
PU Pergamon-elsevier Science Ltd
VL 167
UT 000403997900003
BP 30
EP 46
DI 10.1016/j.quascirev.2017.04.021
ID 53148
ER

EF