Characteristics of the natural remanent magnetization (NRM) of a core collected from offshore Wilkes Land, East Antarctica
Paleomagnetic and rockmagnetic studies were carried out in order to investigate the characteristics of natural remanent magnetization (NRM) of deep-sea sediments cored from offshore Wilkes Land, East Antarctica. The core is 540cm long. Alternating-field (AF) demagnetization experiments using a stepw...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
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National Institute of Polar Research
2003-11-01
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| Series: | Antarctic Record |
| Online Access: | http://doi.org/10.15094/00009269 |
| _version_ | 1818230676145569792 |
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| author | Haruka Matsuoka Minoru Funaki |
| author_facet | Haruka Matsuoka Minoru Funaki |
| author_sort | Haruka Matsuoka |
| collection | DOAJ |
| description | Paleomagnetic and rockmagnetic studies were carried out in order to investigate the characteristics of natural remanent magnetization (NRM) of deep-sea sediments cored from offshore Wilkes Land, East Antarctica. The core is 540cm long. Alternating-field (AF) demagnetization experiments using a stepwise AF field from5to100mTwereconductedonallofthesamples. TheNRMintensitiesare10-100 times higher than those commonly obtained from different localities. In the upper 460cm of the core, most samples had stable single component magnetization, and remarkable high-stability components which survived up to 100mT were observed. In the lower section of the core, in contrast, many samples showed more unstable (zigzag) demagnetization curves and secondary acquired magnetizations. The optimum AF demagnetization field intensity was assumed to be 30mT, because the secondary magnetizations of every sample seemed to be completely demagnetized at that AF field. The down core NRM variation after demagnetization by the optimum field revealed that the core contains 3 polarity intervals. By using smaller cubic samples of 1cc volume, the time resolution of the paleomagnetic record was much improved. Anhysteretic remanent magnetization (ARM) experiments were also conducted on all of the samples. The results of the AF demagnetization of ARM imply that the samples showing only soft NRM component possibly acquired their magnetization under a weak geomagnetic field. |
| first_indexed | 2024-12-12T10:38:17Z |
| format | Article |
| id | doaj.art-6fd9cd2af4774e3fbd612d1a5af94ae3 |
| institution | Directory Open Access Journal |
| issn | 0085-7289 2432-079X |
| language | English |
| last_indexed | 2024-12-12T10:38:17Z |
| publishDate | 2003-11-01 |
| publisher | National Institute of Polar Research |
| record_format | Article |
| series | Antarctic Record |
| spelling | doaj.art-6fd9cd2af4774e3fbd612d1a5af94ae32022-12-22T00:27:09ZengNational Institute of Polar ResearchAntarctic Record0085-72892432-079X2003-11-0147331532710.15094/00009269Characteristics of the natural remanent magnetization (NRM) of a core collected from offshore Wilkes Land, East AntarcticaHaruka Matsuoka0Minoru Funaki1Department of Polar Science, School of Mathematical and Physical Science, The Graduated University for Advanced StudiesNational Institute of Polar Research Paleomagnetic and rockmagnetic studies were carried out in order to investigate the characteristics of natural remanent magnetization (NRM) of deep-sea sediments cored from offshore Wilkes Land, East Antarctica. The core is 540cm long. Alternating-field (AF) demagnetization experiments using a stepwise AF field from5to100mTwereconductedonallofthesamples. TheNRMintensitiesare10-100 times higher than those commonly obtained from different localities. In the upper 460cm of the core, most samples had stable single component magnetization, and remarkable high-stability components which survived up to 100mT were observed. In the lower section of the core, in contrast, many samples showed more unstable (zigzag) demagnetization curves and secondary acquired magnetizations. The optimum AF demagnetization field intensity was assumed to be 30mT, because the secondary magnetizations of every sample seemed to be completely demagnetized at that AF field. The down core NRM variation after demagnetization by the optimum field revealed that the core contains 3 polarity intervals. By using smaller cubic samples of 1cc volume, the time resolution of the paleomagnetic record was much improved. Anhysteretic remanent magnetization (ARM) experiments were also conducted on all of the samples. The results of the AF demagnetization of ARM imply that the samples showing only soft NRM component possibly acquired their magnetization under a weak geomagnetic field.http://doi.org/10.15094/00009269 |
| spellingShingle | Haruka Matsuoka Minoru Funaki Characteristics of the natural remanent magnetization (NRM) of a core collected from offshore Wilkes Land, East Antarctica Antarctic Record |
| title | Characteristics of the natural remanent magnetization (NRM) of a core collected from offshore Wilkes Land, East Antarctica |
| title_full | Characteristics of the natural remanent magnetization (NRM) of a core collected from offshore Wilkes Land, East Antarctica |
| title_fullStr | Characteristics of the natural remanent magnetization (NRM) of a core collected from offshore Wilkes Land, East Antarctica |
| title_full_unstemmed | Characteristics of the natural remanent magnetization (NRM) of a core collected from offshore Wilkes Land, East Antarctica |
| title_short | Characteristics of the natural remanent magnetization (NRM) of a core collected from offshore Wilkes Land, East Antarctica |
| title_sort | characteristics of the natural remanent magnetization nrm of a core collected from offshore wilkes land east antarctica |
| url | http://doi.org/10.15094/00009269 |
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