Saved in:
Bibliographic Details
Main Authors: Xuang, Chuang, Channell, James E T, Polyak, Leonid, Darby, Dennis A
Format: Dataset Open Access
Language:en
Published: PANGAEA 2013
Subjects:
Online Access:https://doi.org/10.1594/PANGAEA.804727
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867168562134646784
author Xuang, Chuang
Channell, James E T
Polyak, Leonid
Darby, Dennis A
author_facet Xuang, Chuang
Channell, James E T
Polyak, Leonid
Darby, Dennis A
collection Datos científicos de ciencias marinas y ambientales
contents 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.
format Dataset Open Access
id pangaea_https___doi_org_10_1594_PANGAEA_804727
institution PANGAEA
language en
publishDate 2013
publisher PANGAEA
record_format pangaea
spellingShingle Component NRM Directions for two sediment cores from the Arctic Ocean
Xuang, Chuang
Channell, James E T
Polyak, Leonid
Darby, Dennis A

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.
title Component NRM Directions for two sediment cores from the Arctic Ocean
topic
url https://doi.org/10.1594/PANGAEA.804727