Role of the Africa Magnetic Anomaly in Controlling the Magnetic Configuration and its Secular Variation
Abstract The configuration of the Earth's main magnetic field and its secular variation are greatly controlled by the nondipole field. This portion of the main field exhibits as 5 planetary‐scale magnetic anomalies in Australia, Africa, Eurasia, North America, and South Atlantic Ocean, as well...
Published in: | Chinese Journal of Geophysics |
---|---|
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Wiley
2009
|
Subjects: | |
Online Access: | http://dx.doi.org/10.1002/cjg2.1402 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fcjg2.1402 https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1002/cjg2.1402 |
id |
crwiley:10.1002/cjg2.1402 |
---|---|
record_format |
openpolar |
spelling |
crwiley:10.1002/cjg2.1402 2024-06-02T08:14:28+00:00 Role of the Africa Magnetic Anomaly in Controlling the Magnetic Configuration and its Secular Variation 2009 http://dx.doi.org/10.1002/cjg2.1402 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fcjg2.1402 https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1002/cjg2.1402 en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor Chinese Journal of Geophysics volume 52, issue 4, page 793-802 ISSN 0898-9591 2326-0440 journal-article 2009 crwiley https://doi.org/10.1002/cjg2.1402 2024-05-03T11:02:51Z Abstract The configuration of the Earth's main magnetic field and its secular variation are greatly controlled by the nondipole field. This portion of the main field exhibits as 5 planetary‐scale magnetic anomalies in Australia, Africa, Eurasia, North America, and South Atlantic Ocean, as well as a few minor anomalies. Only anomaly in the equatorial region is the Africa anomaly, which affects seriously the shape and position of the magnetic equator, pushing the equator northward for 15° at maximum. The fast westward drift of the Africa anomaly results in a major secular variation cell ( Ż max > 200 nT/a for 1900~2005) in Central America on the west of the anomaly. In addition, the secular variations of the Africa and South Atlantic Ocean anomalies seriously distort the geomagnetic field in the western hemisphere, implying its causal relation with the polarity reversed patches on the core‐mantle boundary. Article in Journal/Newspaper South Atlantic Ocean Wiley Online Library Chinese Journal of Geophysics 52 4 793 802 |
institution |
Open Polar |
collection |
Wiley Online Library |
op_collection_id |
crwiley |
language |
English |
description |
Abstract The configuration of the Earth's main magnetic field and its secular variation are greatly controlled by the nondipole field. This portion of the main field exhibits as 5 planetary‐scale magnetic anomalies in Australia, Africa, Eurasia, North America, and South Atlantic Ocean, as well as a few minor anomalies. Only anomaly in the equatorial region is the Africa anomaly, which affects seriously the shape and position of the magnetic equator, pushing the equator northward for 15° at maximum. The fast westward drift of the Africa anomaly results in a major secular variation cell ( Ż max > 200 nT/a for 1900~2005) in Central America on the west of the anomaly. In addition, the secular variations of the Africa and South Atlantic Ocean anomalies seriously distort the geomagnetic field in the western hemisphere, implying its causal relation with the polarity reversed patches on the core‐mantle boundary. |
format |
Article in Journal/Newspaper |
title |
Role of the Africa Magnetic Anomaly in Controlling the Magnetic Configuration and its Secular Variation |
spellingShingle |
Role of the Africa Magnetic Anomaly in Controlling the Magnetic Configuration and its Secular Variation |
title_short |
Role of the Africa Magnetic Anomaly in Controlling the Magnetic Configuration and its Secular Variation |
title_full |
Role of the Africa Magnetic Anomaly in Controlling the Magnetic Configuration and its Secular Variation |
title_fullStr |
Role of the Africa Magnetic Anomaly in Controlling the Magnetic Configuration and its Secular Variation |
title_full_unstemmed |
Role of the Africa Magnetic Anomaly in Controlling the Magnetic Configuration and its Secular Variation |
title_sort |
role of the africa magnetic anomaly in controlling the magnetic configuration and its secular variation |
publisher |
Wiley |
publishDate |
2009 |
url |
http://dx.doi.org/10.1002/cjg2.1402 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fcjg2.1402 https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1002/cjg2.1402 |
genre |
South Atlantic Ocean |
genre_facet |
South Atlantic Ocean |
op_source |
Chinese Journal of Geophysics volume 52, issue 4, page 793-802 ISSN 0898-9591 2326-0440 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1002/cjg2.1402 |
container_title |
Chinese Journal of Geophysics |
container_volume |
52 |
container_issue |
4 |
container_start_page |
793 |
op_container_end_page |
802 |
_version_ |
1800738346642702336 |