The University of Southampton
University of Southampton Institutional Repository

Paleomagnetism of Quaternary sediments from Lomonosov Ridge and Yermak Plateau: implications for age models in the Arctic Ocean

Paleomagnetism of Quaternary sediments from Lomonosov Ridge and Yermak Plateau: implications for age models in the Arctic Ocean
Paleomagnetism of Quaternary sediments from Lomonosov Ridge and Yermak Plateau: implications for age models in the Arctic Ocean
Inclination patterns of natural remanent magnetization (NRM) in Quaternary sediment cores from the Arctic Ocean have been widely used for stratigraphic correlation and the construction of age models, however, shallow and negative NRM inclinations in sediments deposited during the Brunhes Chron in the Arctic Ocean appear to have a partly diagenetic origin. Rock magnetic and mineralogical studies demonstrate the presence of titanomagnetite and titanomaghemite. Thermal demagnetization of the NRM indicates that shallow and negative inclination components are largely “unblocked” below ?300 °C, consistent with a titanomaghemite remanence carrier. Following earlier studies on the Mendeleev–Alpha Ridge, shallow and negative NRM inclination intervals in cores from the Lomonosov Ridge and Yermak Plateau are attributed to partial self-reversed chemical remanent magnetization (CRM) carried by titanomaghemite formed during seafloor oxidation of host (detrital) titanomagnetite grains. Distortion of paleomagnetic records due to seafloor maghemitization appears to be especially important in the perennially ice covered western (Mendeleev–Alpha Ridge) and central Arctic Ocean (Lomonosov Ridge) and, to a lesser extent, near the ice edge (Yermak Plateau). On the Yermak Plateau, magnetic grain size parameters mimic the global benthic oxygen isotope record back to at least marine isotope stage 6, implying that magnetic grain size is sensitive to glacial–interglacial changes in bottom-current velocity and/or detrital provenance.
lomonosov ridge, yermak plateau, magnetic excursions, titanomaghemite, self-reversal
0277-3791
48-63
Xuan, Chuang
3f3cad12-b17b-46ae-957a-b362def5b837
Channell, James E.T.
55b6c1cc-76e7-4ca5-8186-d9111b9b5158
Polyak, Leonid
d98748c7-21e7-4850-9ce4-d6cacdb7ba50
Darby, Dennis A.
76289b79-cbea-45f0-bf14-10177bf26b7b
Xuan, Chuang
3f3cad12-b17b-46ae-957a-b362def5b837
Channell, James E.T.
55b6c1cc-76e7-4ca5-8186-d9111b9b5158
Polyak, Leonid
d98748c7-21e7-4850-9ce4-d6cacdb7ba50
Darby, Dennis A.
76289b79-cbea-45f0-bf14-10177bf26b7b

Xuan, Chuang, Channell, James E.T., Polyak, Leonid and Darby, Dennis A. (2012) Paleomagnetism of Quaternary sediments from Lomonosov Ridge and Yermak Plateau: implications for age models in the Arctic Ocean. Quaternary Science Reviews, 32, 48-63. (doi:10.1016/j.quascirev.2011.11.015).

Record type: Article

Abstract

Inclination patterns of natural remanent magnetization (NRM) in Quaternary sediment cores from the Arctic Ocean have been widely used for stratigraphic correlation and the construction of age models, however, shallow and negative NRM inclinations in sediments deposited during the Brunhes Chron in the Arctic Ocean appear to have a partly diagenetic origin. Rock magnetic and mineralogical studies demonstrate the presence of titanomagnetite and titanomaghemite. Thermal demagnetization of the NRM indicates that shallow and negative inclination components are largely “unblocked” below ?300 °C, consistent with a titanomaghemite remanence carrier. Following earlier studies on the Mendeleev–Alpha Ridge, shallow and negative NRM inclination intervals in cores from the Lomonosov Ridge and Yermak Plateau are attributed to partial self-reversed chemical remanent magnetization (CRM) carried by titanomaghemite formed during seafloor oxidation of host (detrital) titanomagnetite grains. Distortion of paleomagnetic records due to seafloor maghemitization appears to be especially important in the perennially ice covered western (Mendeleev–Alpha Ridge) and central Arctic Ocean (Lomonosov Ridge) and, to a lesser extent, near the ice edge (Yermak Plateau). On the Yermak Plateau, magnetic grain size parameters mimic the global benthic oxygen isotope record back to at least marine isotope stage 6, implying that magnetic grain size is sensitive to glacial–interglacial changes in bottom-current velocity and/or detrital provenance.

This record has no associated files available for download.

More information

Published date: 16 January 2012
Keywords: lomonosov ridge, yermak plateau, magnetic excursions, titanomaghemite, self-reversal
Organisations: Ocean and Earth Science

Identifiers

Local EPrints ID: 351179
URI: http://eprints.soton.ac.uk/id/eprint/351179
ISSN: 0277-3791
PURE UUID: b9f95a97-ef8d-4411-8128-2efb4e3a467c
ORCID for Chuang Xuan: ORCID iD orcid.org/0000-0003-4043-3073

Catalogue record

Date deposited: 16 Apr 2013 08:37
Last modified: 10 Jan 2022 03:01

Export record

Altmetrics

Contributors

Author: Chuang Xuan ORCID iD
Author: James E.T. Channell
Author: Leonid Polyak
Author: Dennis A. Darby

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.

×