Paleomagnetic inclination variations during the last 200 kyr in the Okhotsk Sea and their relation to persistent non-axial-dipole field
Abstract Studies on geomagnetic paleointensity using marine sediments revealed that intensity fluctuations contain variations with timescales of 10 4 years and longer. In contrast, directional secular variations of such timescales were far less studied. In this paper we study inclination variations...
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ftbiomed:oai:biomedcentral.com:s40623-016-0561-7 2023-05-15T17:52:32+02:00 Paleomagnetic inclination variations during the last 200 kyr in the Okhotsk Sea and their relation to persistent non-axial-dipole field Yamazaki, Toshitsugu Shimono, Takaya Inoue, Seiko 2016-11-09 http://www.earth-planets-space.com/content/68/1/174 en eng BioMed Central Ltd. http://www.earth-planets-space.com/content/68/1/174 Copyright 2016 The Author(s) Paleomagnetism Inclination Paleointensity Non-axial-dipole Okhotsk Sea Western equatorial Pacific Letter 2016 ftbiomed 2016-11-27T01:01:53Z Abstract Studies on geomagnetic paleointensity using marine sediments revealed that intensity fluctuations contain variations with timescales of 10 4 years and longer. In contrast, directional secular variations of such timescales were far less studied. In this paper we study inclination variations of longer than a millennial timescale using sediment cores at nine sites in the Okhotsk Sea. Relative paleointensity and magnetic susceptibility variations were used for inter-core correlations and age estimations. The average inclinations of individual cores were close to those of the geocentric axial dipole (GAD) field at the site latitudes. A stacked inclination curve for the last 200 kyr showed intervals of shallower inclinations at about 25–45, 75–90, 110–135, and 185–200 ka. These are synchronous with inclination shifts toward negative previously reported in the western equatorial Pacific, and temporally coincide with paleointensity lows in general. Both the Okhotsk Sea and western equatorial Pacific are within a region of outward directed flux in the persistent non-axial-dipole (NAD) field, and the synchronous inclination shifts may have been caused by a larger contribution of the NAD field when the GAD was weaker. Graphical Abstract . Manuscript okhotsk sea BioMed Central Okhotsk Pacific |
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Open Polar |
collection |
BioMed Central |
op_collection_id |
ftbiomed |
language |
English |
topic |
Paleomagnetism Inclination Paleointensity Non-axial-dipole Okhotsk Sea Western equatorial Pacific |
spellingShingle |
Paleomagnetism Inclination Paleointensity Non-axial-dipole Okhotsk Sea Western equatorial Pacific Yamazaki, Toshitsugu Shimono, Takaya Inoue, Seiko Paleomagnetic inclination variations during the last 200 kyr in the Okhotsk Sea and their relation to persistent non-axial-dipole field |
topic_facet |
Paleomagnetism Inclination Paleointensity Non-axial-dipole Okhotsk Sea Western equatorial Pacific |
description |
Abstract Studies on geomagnetic paleointensity using marine sediments revealed that intensity fluctuations contain variations with timescales of 10 4 years and longer. In contrast, directional secular variations of such timescales were far less studied. In this paper we study inclination variations of longer than a millennial timescale using sediment cores at nine sites in the Okhotsk Sea. Relative paleointensity and magnetic susceptibility variations were used for inter-core correlations and age estimations. The average inclinations of individual cores were close to those of the geocentric axial dipole (GAD) field at the site latitudes. A stacked inclination curve for the last 200 kyr showed intervals of shallower inclinations at about 25–45, 75–90, 110–135, and 185–200 ka. These are synchronous with inclination shifts toward negative previously reported in the western equatorial Pacific, and temporally coincide with paleointensity lows in general. Both the Okhotsk Sea and western equatorial Pacific are within a region of outward directed flux in the persistent non-axial-dipole (NAD) field, and the synchronous inclination shifts may have been caused by a larger contribution of the NAD field when the GAD was weaker. Graphical Abstract . |
format |
Manuscript |
author |
Yamazaki, Toshitsugu Shimono, Takaya Inoue, Seiko |
author_facet |
Yamazaki, Toshitsugu Shimono, Takaya Inoue, Seiko |
author_sort |
Yamazaki, Toshitsugu |
title |
Paleomagnetic inclination variations during the last 200 kyr in the Okhotsk Sea and their relation to persistent non-axial-dipole field |
title_short |
Paleomagnetic inclination variations during the last 200 kyr in the Okhotsk Sea and their relation to persistent non-axial-dipole field |
title_full |
Paleomagnetic inclination variations during the last 200 kyr in the Okhotsk Sea and their relation to persistent non-axial-dipole field |
title_fullStr |
Paleomagnetic inclination variations during the last 200 kyr in the Okhotsk Sea and their relation to persistent non-axial-dipole field |
title_full_unstemmed |
Paleomagnetic inclination variations during the last 200 kyr in the Okhotsk Sea and their relation to persistent non-axial-dipole field |
title_sort |
paleomagnetic inclination variations during the last 200 kyr in the okhotsk sea and their relation to persistent non-axial-dipole field |
publisher |
BioMed Central Ltd. |
publishDate |
2016 |
url |
http://www.earth-planets-space.com/content/68/1/174 |
geographic |
Okhotsk Pacific |
geographic_facet |
Okhotsk Pacific |
genre |
okhotsk sea |
genre_facet |
okhotsk sea |
op_relation |
http://www.earth-planets-space.com/content/68/1/174 |
op_rights |
Copyright 2016 The Author(s) |
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1766160053531836416 |