Constraining the terrestrial age of micrometeorites using their record of the Earth's magnetic field polarity
We propose a new nondestructive method that uses the paleomagnetic record of micrometeorites in Earth's polar regions to constrain the age of their fall. During atmospheric entry, melted micrometeorites acquire a thermal remanent magnetization and record the polar subvertical geomagnetic field....
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Format: | Article in Journal/Newspaper |
Language: | English |
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2011
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Online Access: | http://hdl.handle.net/11568/148523 https://doi.org/10.1130/G31655.1 |
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ftunivpisairis:oai:arpi.unipi.it:11568/148523 2024-04-14T08:03:52+00:00 Constraining the terrestrial age of micrometeorites using their record of the Earth's magnetic field polarity Suavet C Gattacceca J Rochette P FOLCO, LUIGI Suavet, C Gattacceca, J Rochette, P Folco, Luigi 2011 STAMPA http://hdl.handle.net/11568/148523 https://doi.org/10.1130/G31655.1 eng eng info:eu-repo/semantics/altIdentifier/wos/WOS:000286505300007 volume:39 firstpage:123 lastpage:126 numberofpages:4 journal:GEOLOGY http://hdl.handle.net/11568/148523 doi:10.1130/G31655.1 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-78851471465 info:eu-repo/semantics/article 2011 ftunivpisairis https://doi.org/10.1130/G31655.1 2024-03-21T19:13:58Z We propose a new nondestructive method that uses the paleomagnetic record of micrometeorites in Earth's polar regions to constrain the age of their fall. During atmospheric entry, melted micrometeorites acquire a thermal remanent magnetization and record the polar subvertical geomagnetic field. When the fall vector can be determined, due to the location of bubbles, iron-nickel droplets, or grain-size gradients, it is possible to ascribe the fall to a normal or reverse polarity interval of the geomagnetic field. We tested this concept on a set of eight melted micrometeorites from the Transantarctic Mountains (Antarctica). Two micrometeorites have magnetization directions consistent with a normal polarity of the Earth's magnetic field, whereas four others have recorded a reverse polarity, and therefore fell to Earth at least 0.78 m.y. ago. One micrometeorite has a magnetization that is seemingly unrelated to the inferred entry direction. The fall direction could not be determined with certainty for one micrometeorite. These results provide new evidence suggesting that the Transantarctic Mountains micrometeorite traps are 1-2 m.y. old, and confirm that they contain the oldest non-fossil micrometeorites available. Article in Journal/Newspaper Antarc* Antarctica ARPI - Archivio della Ricerca dell'Università di Pisa Transantarctic Mountains Geology 39 2 123 126 |
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Open Polar |
collection |
ARPI - Archivio della Ricerca dell'Università di Pisa |
op_collection_id |
ftunivpisairis |
language |
English |
description |
We propose a new nondestructive method that uses the paleomagnetic record of micrometeorites in Earth's polar regions to constrain the age of their fall. During atmospheric entry, melted micrometeorites acquire a thermal remanent magnetization and record the polar subvertical geomagnetic field. When the fall vector can be determined, due to the location of bubbles, iron-nickel droplets, or grain-size gradients, it is possible to ascribe the fall to a normal or reverse polarity interval of the geomagnetic field. We tested this concept on a set of eight melted micrometeorites from the Transantarctic Mountains (Antarctica). Two micrometeorites have magnetization directions consistent with a normal polarity of the Earth's magnetic field, whereas four others have recorded a reverse polarity, and therefore fell to Earth at least 0.78 m.y. ago. One micrometeorite has a magnetization that is seemingly unrelated to the inferred entry direction. The fall direction could not be determined with certainty for one micrometeorite. These results provide new evidence suggesting that the Transantarctic Mountains micrometeorite traps are 1-2 m.y. old, and confirm that they contain the oldest non-fossil micrometeorites available. |
author2 |
Suavet, C Gattacceca, J Rochette, P Folco, Luigi |
format |
Article in Journal/Newspaper |
author |
Suavet C Gattacceca J Rochette P FOLCO, LUIGI |
spellingShingle |
Suavet C Gattacceca J Rochette P FOLCO, LUIGI Constraining the terrestrial age of micrometeorites using their record of the Earth's magnetic field polarity |
author_facet |
Suavet C Gattacceca J Rochette P FOLCO, LUIGI |
author_sort |
Suavet C |
title |
Constraining the terrestrial age of micrometeorites using their record of the Earth's magnetic field polarity |
title_short |
Constraining the terrestrial age of micrometeorites using their record of the Earth's magnetic field polarity |
title_full |
Constraining the terrestrial age of micrometeorites using their record of the Earth's magnetic field polarity |
title_fullStr |
Constraining the terrestrial age of micrometeorites using their record of the Earth's magnetic field polarity |
title_full_unstemmed |
Constraining the terrestrial age of micrometeorites using their record of the Earth's magnetic field polarity |
title_sort |
constraining the terrestrial age of micrometeorites using their record of the earth's magnetic field polarity |
publishDate |
2011 |
url |
http://hdl.handle.net/11568/148523 https://doi.org/10.1130/G31655.1 |
geographic |
Transantarctic Mountains |
geographic_facet |
Transantarctic Mountains |
genre |
Antarc* Antarctica |
genre_facet |
Antarc* Antarctica |
op_relation |
info:eu-repo/semantics/altIdentifier/wos/WOS:000286505300007 volume:39 firstpage:123 lastpage:126 numberofpages:4 journal:GEOLOGY http://hdl.handle.net/11568/148523 doi:10.1130/G31655.1 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-78851471465 |
op_doi |
https://doi.org/10.1130/G31655.1 |
container_title |
Geology |
container_volume |
39 |
container_issue |
2 |
container_start_page |
123 |
op_container_end_page |
126 |
_version_ |
1796300178915852288 |