Aeromagnetic and Radio Echo Ice-Sounding Measurements Show Much Greater Area of the Dufek Intrusion, Antarctica
A combined aeromagnetic and radio echo ice-sounding survey made in 1978 in Antarctica over the Dufek layered mafic intrusion suggests a minimum area of the intrusion of about 50,000 square kilometers, making it comparable in size with the Bushveld Complex of Africa. Comparisons of the magnetic and s...
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American Association for the Advancement of Science (AAAS)
1980
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Online Access: | http://dx.doi.org/10.1126/science.209.4460.1014 https://www.science.org/doi/pdf/10.1126/science.209.4460.1014 |
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craaas:10.1126/science.209.4460.1014 2024-06-09T07:40:47+00:00 Aeromagnetic and Radio Echo Ice-Sounding Measurements Show Much Greater Area of the Dufek Intrusion, Antarctica Behrendt, John C. Drewry, David J. Jankowski, Edward Grim, Muriel S. 1980 http://dx.doi.org/10.1126/science.209.4460.1014 https://www.science.org/doi/pdf/10.1126/science.209.4460.1014 en eng American Association for the Advancement of Science (AAAS) Science volume 209, issue 4460, page 1014-1017 ISSN 0036-8075 1095-9203 journal-article 1980 craaas https://doi.org/10.1126/science.209.4460.1014 2024-05-16T12:55:30Z A combined aeromagnetic and radio echo ice-sounding survey made in 1978 in Antarctica over the Dufek layered mafic intrusion suggests a minimum area of the intrusion of about 50,000 square kilometers, making it comparable in size with the Bushveld Complex of Africa. Comparisons of the magnetic and subglacial topographic profiles illustrate the usefulness of this combination of methods in studying bedrock geology beneath ice-covered areas. Magnetic anomalies range in peak-to-trough amplitude from about 50 nanoteslas over the lowermost exposed portion of the section in the Dufek Massif to about 3600 nanoteslas over the uppermost part of the section in the Forrestal Range. Theoretical magnetic anomalies, computed from a model based on the subice topography fitted to the highest amplitude observed magnetic anomalies, required normal and reversed magnetizations ranging from 10 -3 to 10 -2 electromagnetic units per cubic centimeter. This result is interpreted as indicating that the Dufek intrusion cooled through the Curie isotherm during one or more reversals of the earth's magnetic field. Article in Journal/Newspaper Antarc* Antarctica ice covered areas AAAS Resource Center (American Association for the Advancement of Science) Dufek Massif ENVELOPE(-52.500,-52.500,-82.500,-82.500) Forrestal Range ENVELOPE(-48.500,-48.500,-82.667,-82.667) Science 209 4460 1014 1017 |
institution |
Open Polar |
collection |
AAAS Resource Center (American Association for the Advancement of Science) |
op_collection_id |
craaas |
language |
English |
description |
A combined aeromagnetic and radio echo ice-sounding survey made in 1978 in Antarctica over the Dufek layered mafic intrusion suggests a minimum area of the intrusion of about 50,000 square kilometers, making it comparable in size with the Bushveld Complex of Africa. Comparisons of the magnetic and subglacial topographic profiles illustrate the usefulness of this combination of methods in studying bedrock geology beneath ice-covered areas. Magnetic anomalies range in peak-to-trough amplitude from about 50 nanoteslas over the lowermost exposed portion of the section in the Dufek Massif to about 3600 nanoteslas over the uppermost part of the section in the Forrestal Range. Theoretical magnetic anomalies, computed from a model based on the subice topography fitted to the highest amplitude observed magnetic anomalies, required normal and reversed magnetizations ranging from 10 -3 to 10 -2 electromagnetic units per cubic centimeter. This result is interpreted as indicating that the Dufek intrusion cooled through the Curie isotherm during one or more reversals of the earth's magnetic field. |
format |
Article in Journal/Newspaper |
author |
Behrendt, John C. Drewry, David J. Jankowski, Edward Grim, Muriel S. |
spellingShingle |
Behrendt, John C. Drewry, David J. Jankowski, Edward Grim, Muriel S. Aeromagnetic and Radio Echo Ice-Sounding Measurements Show Much Greater Area of the Dufek Intrusion, Antarctica |
author_facet |
Behrendt, John C. Drewry, David J. Jankowski, Edward Grim, Muriel S. |
author_sort |
Behrendt, John C. |
title |
Aeromagnetic and Radio Echo Ice-Sounding Measurements Show Much Greater Area of the Dufek Intrusion, Antarctica |
title_short |
Aeromagnetic and Radio Echo Ice-Sounding Measurements Show Much Greater Area of the Dufek Intrusion, Antarctica |
title_full |
Aeromagnetic and Radio Echo Ice-Sounding Measurements Show Much Greater Area of the Dufek Intrusion, Antarctica |
title_fullStr |
Aeromagnetic and Radio Echo Ice-Sounding Measurements Show Much Greater Area of the Dufek Intrusion, Antarctica |
title_full_unstemmed |
Aeromagnetic and Radio Echo Ice-Sounding Measurements Show Much Greater Area of the Dufek Intrusion, Antarctica |
title_sort |
aeromagnetic and radio echo ice-sounding measurements show much greater area of the dufek intrusion, antarctica |
publisher |
American Association for the Advancement of Science (AAAS) |
publishDate |
1980 |
url |
http://dx.doi.org/10.1126/science.209.4460.1014 https://www.science.org/doi/pdf/10.1126/science.209.4460.1014 |
long_lat |
ENVELOPE(-52.500,-52.500,-82.500,-82.500) ENVELOPE(-48.500,-48.500,-82.667,-82.667) |
geographic |
Dufek Massif Forrestal Range |
geographic_facet |
Dufek Massif Forrestal Range |
genre |
Antarc* Antarctica ice covered areas |
genre_facet |
Antarc* Antarctica ice covered areas |
op_source |
Science volume 209, issue 4460, page 1014-1017 ISSN 0036-8075 1095-9203 |
op_doi |
https://doi.org/10.1126/science.209.4460.1014 |
container_title |
Science |
container_volume |
209 |
container_issue |
4460 |
container_start_page |
1014 |
op_container_end_page |
1017 |
_version_ |
1801369187441967104 |