New Archeomagnetic Directional Records From Iron Age Southern Africa (ca. 425–1550 CE) and Implications for the South Atlantic Anomaly
Abstract The paucity of Southern Hemisphere archeomagnetic data limits the resolution of paleosecular variation models. At the same time, important changes in the modern and historical field, including the recent dipole decay, appear to originate in this region. Here a new directional record from so...
Saved in:
| Main Authors: | , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2018-02-01
|
| Series: | Geophysical Research Letters |
| Subjects: | |
| Online Access: | https://doi.org/10.1002/2017GL076007 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850272637318594560 |
|---|---|
| author | Vincent J. Hare John A. Tarduno Thomas Huffman Michael Watkeys Phenyo C. Thebe Munyaradzi Manyanga Richard K. Bono Rory D. Cottrell |
| author_facet | Vincent J. Hare John A. Tarduno Thomas Huffman Michael Watkeys Phenyo C. Thebe Munyaradzi Manyanga Richard K. Bono Rory D. Cottrell |
| author_sort | Vincent J. Hare |
| collection | DOAJ |
| description | Abstract The paucity of Southern Hemisphere archeomagnetic data limits the resolution of paleosecular variation models. At the same time, important changes in the modern and historical field, including the recent dipole decay, appear to originate in this region. Here a new directional record from southern Africa is presented from analysis of Iron Age (ca. 425–1550 CE) archeological materials, which extends the regional secular variation curve back to the first millennium. Previous studies have identified a period of rapid directional change between 1225 and ∼1550 CE. The new data allow us to identify an earlier period of relatively rapid change between the sixth and seventh centuries CE. Implications for models of recurrent flux expulsion at the core‐mantle boundary are discussed. In addition, we identify a possible relationship of changes recorded in these African data with archeomagnetic jerks. |
| format | Article |
| id | doaj-art-c7e3e85ef9974c8e98bc84133fed5089 |
| institution | OA Journals |
| issn | 0094-8276 1944-8007 |
| language | English |
| publishDate | 2018-02-01 |
| publisher | Wiley |
| record_format | Article |
| series | Geophysical Research Letters |
| spelling | doaj-art-c7e3e85ef9974c8e98bc84133fed50892025-08-20T01:51:44ZengWileyGeophysical Research Letters0094-82761944-80072018-02-014531361136910.1002/2017GL076007New Archeomagnetic Directional Records From Iron Age Southern Africa (ca. 425–1550 CE) and Implications for the South Atlantic AnomalyVincent J. Hare0John A. Tarduno1Thomas Huffman2Michael Watkeys3Phenyo C. Thebe4Munyaradzi Manyanga5Richard K. Bono6Rory D. Cottrell7Department of Earth and Environmental Sciences University of Rochester Rochester NY USADepartment of Earth and Environmental Sciences University of Rochester Rochester NY USASchool of Geography, Archaeology and Environmental Studies University of the Witwatersrand Johannesburg South AfricaSchool of Geological Sciences University of KwaZulu‐Natal Durban South AfricaArchaeology Unit, Department of History University of Botswana Gaborone BotswanaHistory Department University of Zimbabwe Harare ZimbabweDepartment of Earth and Environmental Sciences University of Rochester Rochester NY USADepartment of Earth and Environmental Sciences University of Rochester Rochester NY USAAbstract The paucity of Southern Hemisphere archeomagnetic data limits the resolution of paleosecular variation models. At the same time, important changes in the modern and historical field, including the recent dipole decay, appear to originate in this region. Here a new directional record from southern Africa is presented from analysis of Iron Age (ca. 425–1550 CE) archeological materials, which extends the regional secular variation curve back to the first millennium. Previous studies have identified a period of rapid directional change between 1225 and ∼1550 CE. The new data allow us to identify an earlier period of relatively rapid change between the sixth and seventh centuries CE. Implications for models of recurrent flux expulsion at the core‐mantle boundary are discussed. In addition, we identify a possible relationship of changes recorded in these African data with archeomagnetic jerks.https://doi.org/10.1002/2017GL076007archeomagnetismSouth Atlantic Anomalygeomagnetismcoresouthern AfricaIron Age |
| spellingShingle | Vincent J. Hare John A. Tarduno Thomas Huffman Michael Watkeys Phenyo C. Thebe Munyaradzi Manyanga Richard K. Bono Rory D. Cottrell New Archeomagnetic Directional Records From Iron Age Southern Africa (ca. 425–1550 CE) and Implications for the South Atlantic Anomaly Geophysical Research Letters archeomagnetism South Atlantic Anomaly geomagnetism core southern Africa Iron Age |
| title | New Archeomagnetic Directional Records From Iron Age Southern Africa (ca. 425–1550 CE) and Implications for the South Atlantic Anomaly |
| title_full | New Archeomagnetic Directional Records From Iron Age Southern Africa (ca. 425–1550 CE) and Implications for the South Atlantic Anomaly |
| title_fullStr | New Archeomagnetic Directional Records From Iron Age Southern Africa (ca. 425–1550 CE) and Implications for the South Atlantic Anomaly |
| title_full_unstemmed | New Archeomagnetic Directional Records From Iron Age Southern Africa (ca. 425–1550 CE) and Implications for the South Atlantic Anomaly |
| title_short | New Archeomagnetic Directional Records From Iron Age Southern Africa (ca. 425–1550 CE) and Implications for the South Atlantic Anomaly |
| title_sort | new archeomagnetic directional records from iron age southern africa ca 425 1550 ce and implications for the south atlantic anomaly |
| topic | archeomagnetism South Atlantic Anomaly geomagnetism core southern Africa Iron Age |
| url | https://doi.org/10.1002/2017GL076007 |
| work_keys_str_mv | AT vincentjhare newarcheomagneticdirectionalrecordsfromironagesouthernafricaca4251550ceandimplicationsforthesouthatlanticanomaly AT johnatarduno newarcheomagneticdirectionalrecordsfromironagesouthernafricaca4251550ceandimplicationsforthesouthatlanticanomaly AT thomashuffman newarcheomagneticdirectionalrecordsfromironagesouthernafricaca4251550ceandimplicationsforthesouthatlanticanomaly AT michaelwatkeys newarcheomagneticdirectionalrecordsfromironagesouthernafricaca4251550ceandimplicationsforthesouthatlanticanomaly AT phenyocthebe newarcheomagneticdirectionalrecordsfromironagesouthernafricaca4251550ceandimplicationsforthesouthatlanticanomaly AT munyaradzimanyanga newarcheomagneticdirectionalrecordsfromironagesouthernafricaca4251550ceandimplicationsforthesouthatlanticanomaly AT richardkbono newarcheomagneticdirectionalrecordsfromironagesouthernafricaca4251550ceandimplicationsforthesouthatlanticanomaly AT rorydcottrell newarcheomagneticdirectionalrecordsfromironagesouthernafricaca4251550ceandimplicationsforthesouthatlanticanomaly |