High-resolution record of the deglaciation of the British-Irish Ice Sheet from North Atlantic deep-sea sediments.

Serena Tarlati, S. Benetti, Louise Callard, Colm O'Cofaigh, P Dunlop, Richard Chiverrell, Derek Fabel, Steven Moreton, Chris D Clark

Research output: Contribution to conferencePoster

Abstract

During the last glacial maximum the British-Irish Ice Sheet (BIIS) covered the majority of Ireland and Britain. Recent studies have described the BIIS as largely marine-based and highly dynamic with several advances and retreats recorded on the continental shelf.
The focus of this study is the more recent sediment record from the Donegal Barra Fan (DBF), the largest sediment depocentre formed by the ice streaming of the western BIIS onto the North Atlantic continental margin.

In this project, well-preserved, glacially-derived, deep-water sediments from 3 cores, up to 6.7 m long and retrieved from the DBF, are used to investigate and chronologically constrain the pattern of deglaciation of the BIIS. Deep-water sediments can record continuous sedimentation through time, avoiding hiatuses and erosional surfaces characteristic of a glacial environment and allow a detailed reconstruction of deglacial processes.

Five lithofacies have been identified using sedimentology, x-rays, physical properties and grain size analysis. They include bioturbated foraminifera-bearing muds, interpreted as hemipelagic and contouritic deposits from interglacial periods. Chaotic and laminated muds, ice-rafted debris (IRD)-rich layers and laminated mud to sand couplets are characteristic of the glacial period including ice-sheet maximum extent and the beginning of retreat. These represent downslope mass movements, plumites from meltwater alongside melting icebergs and turbidites. Radiocarbon dates from foraminifera suggest that the deglacial sedimentary sequence is up to 5m thick. The IRD concentration and abundance of the foraminifera Neogloboquadrina pachyderma sinistral indicate a minimum of 3 different calving events during deglaciation and a marked Younger Dryas cooling and ice calving period. Additionally the δ 18O record will be used to investigate the record of climatic changes in the region and x-ray fluorescence will be used to assess sediment provenance during deglaciation.

Conference

ConferenceAmerican Geophysical Union
Abbreviated titleAGU Fall Meeting
CountryUnited States
CitySan Francisco
Period12/12/1616/12/16

Fingerprint

deep-sea sediment
deglaciation
ice sheet
foraminifera
ice-rafted debris
mud
sediment
deep water
glacial environment
ice
iceberg
depocenter
mass movement
Younger Dryas
sedimentology
lithofacies
sedimentary sequence
Last Glacial Maximum
meltwater
interglacial

Keywords

  • British Irish Ice Sheet
  • Deglaciation
  • Donegal-Barra Fan

Cite this

Tarlati, S., Benetti, S., Callard, L., O'Cofaigh, C., Dunlop, P., Chiverrell, R., ... Clark, C. D. (2016). High-resolution record of the deglaciation of the British-Irish Ice Sheet from North Atlantic deep-sea sediments.. Poster session presented at American Geophysical Union, San Francisco, United States.
Tarlati, Serena ; Benetti, S. ; Callard, Louise ; O'Cofaigh, Colm ; Dunlop, P ; Chiverrell, Richard ; Fabel, Derek ; Moreton, Steven ; Clark, Chris D. / High-resolution record of the deglaciation of the British-Irish Ice Sheet from North Atlantic deep-sea sediments. Poster session presented at American Geophysical Union, San Francisco, United States.1 p.
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abstract = "During the last glacial maximum the British-Irish Ice Sheet (BIIS) covered the majority of Ireland and Britain. Recent studies have described the BIIS as largely marine-based and highly dynamic with several advances and retreats recorded on the continental shelf. The focus of this study is the more recent sediment record from the Donegal Barra Fan (DBF), the largest sediment depocentre formed by the ice streaming of the western BIIS onto the North Atlantic continental margin. In this project, well-preserved, glacially-derived, deep-water sediments from 3 cores, up to 6.7 m long and retrieved from the DBF, are used to investigate and chronologically constrain the pattern of deglaciation of the BIIS. Deep-water sediments can record continuous sedimentation through time, avoiding hiatuses and erosional surfaces characteristic of a glacial environment and allow a detailed reconstruction of deglacial processes. Five lithofacies have been identified using sedimentology, x-rays, physical properties and grain size analysis. They include bioturbated foraminifera-bearing muds, interpreted as hemipelagic and contouritic deposits from interglacial periods. Chaotic and laminated muds, ice-rafted debris (IRD)-rich layers and laminated mud to sand couplets are characteristic of the glacial period including ice-sheet maximum extent and the beginning of retreat. These represent downslope mass movements, plumites from meltwater alongside melting icebergs and turbidites. Radiocarbon dates from foraminifera suggest that the deglacial sedimentary sequence is up to 5m thick. The IRD concentration and abundance of the foraminifera Neogloboquadrina pachyderma sinistral indicate a minimum of 3 different calving events during deglaciation and a marked Younger Dryas cooling and ice calving period. Additionally the δ 18O record will be used to investigate the record of climatic changes in the region and x-ray fluorescence will be used to assess sediment provenance during deglaciation.",
keywords = "British Irish Ice Sheet, Deglaciation, Donegal-Barra Fan",
author = "Serena Tarlati and S. Benetti and Louise Callard and Colm O'Cofaigh and P Dunlop and Richard Chiverrell and Derek Fabel and Steven Moreton and Clark, {Chris D}",
note = "Conference poster; American Geophysical Union : Fall Meeting, AGU Fall Meeting ; Conference date: 12-12-2016 Through 16-12-2016",
year = "2016",
month = "12",
day = "16",
language = "English",

}

Tarlati, S, Benetti, S, Callard, L, O'Cofaigh, C, Dunlop, P, Chiverrell, R, Fabel, D, Moreton, S & Clark, CD 2016, 'High-resolution record of the deglaciation of the British-Irish Ice Sheet from North Atlantic deep-sea sediments.' American Geophysical Union, San Francisco, United States, 12/12/16 - 16/12/16, .

High-resolution record of the deglaciation of the British-Irish Ice Sheet from North Atlantic deep-sea sediments. / Tarlati, Serena; Benetti, S.; Callard, Louise; O'Cofaigh, Colm; Dunlop, P; Chiverrell, Richard; Fabel, Derek ; Moreton, Steven; Clark, Chris D.

2016. Poster session presented at American Geophysical Union, San Francisco, United States.

Research output: Contribution to conferencePoster

TY - CONF

T1 - High-resolution record of the deglaciation of the British-Irish Ice Sheet from North Atlantic deep-sea sediments.

AU - Tarlati, Serena

AU - Benetti, S.

AU - Callard, Louise

AU - O'Cofaigh, Colm

AU - Dunlop, P

AU - Chiverrell, Richard

AU - Fabel, Derek

AU - Moreton, Steven

AU - Clark, Chris D

N1 - Conference poster

PY - 2016/12/16

Y1 - 2016/12/16

N2 - During the last glacial maximum the British-Irish Ice Sheet (BIIS) covered the majority of Ireland and Britain. Recent studies have described the BIIS as largely marine-based and highly dynamic with several advances and retreats recorded on the continental shelf. The focus of this study is the more recent sediment record from the Donegal Barra Fan (DBF), the largest sediment depocentre formed by the ice streaming of the western BIIS onto the North Atlantic continental margin. In this project, well-preserved, glacially-derived, deep-water sediments from 3 cores, up to 6.7 m long and retrieved from the DBF, are used to investigate and chronologically constrain the pattern of deglaciation of the BIIS. Deep-water sediments can record continuous sedimentation through time, avoiding hiatuses and erosional surfaces characteristic of a glacial environment and allow a detailed reconstruction of deglacial processes. Five lithofacies have been identified using sedimentology, x-rays, physical properties and grain size analysis. They include bioturbated foraminifera-bearing muds, interpreted as hemipelagic and contouritic deposits from interglacial periods. Chaotic and laminated muds, ice-rafted debris (IRD)-rich layers and laminated mud to sand couplets are characteristic of the glacial period including ice-sheet maximum extent and the beginning of retreat. These represent downslope mass movements, plumites from meltwater alongside melting icebergs and turbidites. Radiocarbon dates from foraminifera suggest that the deglacial sedimentary sequence is up to 5m thick. The IRD concentration and abundance of the foraminifera Neogloboquadrina pachyderma sinistral indicate a minimum of 3 different calving events during deglaciation and a marked Younger Dryas cooling and ice calving period. Additionally the δ 18O record will be used to investigate the record of climatic changes in the region and x-ray fluorescence will be used to assess sediment provenance during deglaciation.

AB - During the last glacial maximum the British-Irish Ice Sheet (BIIS) covered the majority of Ireland and Britain. Recent studies have described the BIIS as largely marine-based and highly dynamic with several advances and retreats recorded on the continental shelf. The focus of this study is the more recent sediment record from the Donegal Barra Fan (DBF), the largest sediment depocentre formed by the ice streaming of the western BIIS onto the North Atlantic continental margin. In this project, well-preserved, glacially-derived, deep-water sediments from 3 cores, up to 6.7 m long and retrieved from the DBF, are used to investigate and chronologically constrain the pattern of deglaciation of the BIIS. Deep-water sediments can record continuous sedimentation through time, avoiding hiatuses and erosional surfaces characteristic of a glacial environment and allow a detailed reconstruction of deglacial processes. Five lithofacies have been identified using sedimentology, x-rays, physical properties and grain size analysis. They include bioturbated foraminifera-bearing muds, interpreted as hemipelagic and contouritic deposits from interglacial periods. Chaotic and laminated muds, ice-rafted debris (IRD)-rich layers and laminated mud to sand couplets are characteristic of the glacial period including ice-sheet maximum extent and the beginning of retreat. These represent downslope mass movements, plumites from meltwater alongside melting icebergs and turbidites. Radiocarbon dates from foraminifera suggest that the deglacial sedimentary sequence is up to 5m thick. The IRD concentration and abundance of the foraminifera Neogloboquadrina pachyderma sinistral indicate a minimum of 3 different calving events during deglaciation and a marked Younger Dryas cooling and ice calving period. Additionally the δ 18O record will be used to investigate the record of climatic changes in the region and x-ray fluorescence will be used to assess sediment provenance during deglaciation.

KW - British Irish Ice Sheet

KW - Deglaciation

KW - Donegal-Barra Fan

UR - https://agu.confex.com/agu/fm16/meetingapp.cgi/Paper/133356

M3 - Poster

ER -

Tarlati S, Benetti S, Callard L, O'Cofaigh C, Dunlop P, Chiverrell R et al. High-resolution record of the deglaciation of the British-Irish Ice Sheet from North Atlantic deep-sea sediments.. 2016. Poster session presented at American Geophysical Union, San Francisco, United States.