
Pattern and timing of the northwestern B arents S ea I ce S heet deglaciation and indications of episodic H olocene deposition
Author(s) -
Rüther Denise Christina,
Bjarnadóttir Lilja Rún,
Junttila Juho,
Husum Katrine,
Rasmussen Tine Lander,
Lucchi Renata Giulia,
Andreassen Karin
Publication year - 2012
Publication title -
boreas
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.95
H-Index - 74
eISSN - 1502-3885
pISSN - 0300-9483
DOI - 10.1111/j.1502-3885.2011.00244.x
Subject(s) - geology , deglaciation , facies , sedimentary depositional environment , deposition (geology) , oceanography , geochemistry , sediment , holocene , geomorphology , structural basin
The origin of two acoustic sediment units has been studied based on lithological facies, chronology and benthic stable isotope values as well as on foraminifera and clay mineral assemblages in six marine sediment cores from K veithola, a small trough west of S pitsbergenbanken on the western B arents S ea margin. We have identified four time slices with characteristic sedimentary environments. Before c. 14.2 cal. ka, rhythmically laminated muds indicate extensive sea ice cover in the area. From c. 13.9 to 14.2 cal. ka, muds rich in ice‐rafted debris were deposited during the disintegration of grounded ice on S pitsbergenbanken. From c. 10.3 to 13.1 cal. ka, sediments with heterogeneous lithologies suggest a shifting influence of suspension settling and iceberg rafting, probably derived from a decaying Barents Sea Ice Sheet in the inner‐fjord and land areas to the north of Kveithola. Holocene deposition was episodic and characterized by the deposition of calcareous sands and shell debris, indicative of strong bottom currents. We speculate that a marked erosional boundary at c. 8.2 cal. ka may have been caused by the S toregga tsunami. Whilst deposition was sparse during the H olocene, K veithola acted as a sediment trap during the preceding deglaciation. Investigation of the deglacial sediments provides unprecedented details on the dynamics and timing of glacial retreat from S pitsbergenbanken.