Magnetic characterization of Cretaceous-Tertiary boundary sediments
Rock magnetic properties across several K-T boundary sections have been investigated to reveal any possible magnetic signature associated with the remains of the impact event at the end of the Cretaceous. Studied sections locations vary in distance to the Chicxulub structure from distal (Agost and C...
Main Authors: | , , , |
---|---|
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Meteoritics & Planetary Science Archives
2007
|
Subjects: | |
Online Access: | https://journals.uair.arizona.edu/index.php/maps/article/view/15484 |
id |
ftunivarizonaojs:oai:journals.uair.arizona.edu:article/15484 |
---|---|
record_format |
openpolar |
spelling |
ftunivarizonaojs:oai:journals.uair.arizona.edu:article/15484 2023-05-15T17:35:15+02:00 Magnetic characterization of Cretaceous-Tertiary boundary sediments VILLASANTE-MARCOS, V. MARTNEZ-RUIZ, F. OSETE, M. L. URRUTIA-FUCUGAUCHI, J. 2007-01-01 application/pdf https://journals.uair.arizona.edu/index.php/maps/article/view/15484 eng eng Meteoritics & Planetary Science Archives https://journals.uair.arizona.edu/index.php/maps/article/view/15484/15472 https://journals.uair.arizona.edu/index.php/maps/article/view/15484 Meteoritics & Planetary Science Archives; Vol 42, No 9 (2007); 1505-1527 1945-5100 1086-9379 ejecta deposition;magnetic properties;K-T boundary;impact markers info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Peer-reviewed Article 2007 ftunivarizonaojs 2020-11-14T17:53:01Z Rock magnetic properties across several K-T boundary sections have been investigated to reveal any possible magnetic signature associated with the remains of the impact event at the end of the Cretaceous. Studied sections locations vary in distance to the Chicxulub structure from distal (Agost and Caravaca, Spain), through closer (ODP Hole 1049A, Blake Nose, North Atlantic), to proximal (El Mimbral and La Lajilla, Mexico). A clear magnetic signature is associated with the fireball layer in the most distal sections, consisting of a sharp increase in susceptibility and saturation isothermal remanent magnetization (SIRM), and a decrease in remanence coercivity. Magnetic properties in these sections point to a distinctive ferrimagnetic phase, probably corresponding to the reported Mg- and Ni-rich, highly oxidized spinels of meteoritic origin. At closer and proximal sections magnetic properties are different. Although there is an increase in susceptibility and SIRM associated with a rusty layer placed on top of the siliciclastic deposit in proximal sections, and with a similar limonitic layer on top of the spherule bed that defines the boundary at Blake Nose, the magnetic properties indicate a mixture of iron oxyhydroxides dominated by fine-grained goethite. Based on previous geochemical studies at Blake Nose and new geochemical and PGE abundance measurements performed in this work at El Mimbral, this goethite-rich layer can be interpreted as an effect of diagenetic remobilization and precipitation of Fe. There is not enough evidence to assert that this Fe concentration layer at proximal sections is directly related to deposition of fine meteoritic material. Magnetic, geochemical, and iridium data reject it as a primary meteoritic phase. Article in Journal/Newspaper North Atlantic Journals at the University of Arizona |
institution |
Open Polar |
collection |
Journals at the University of Arizona |
op_collection_id |
ftunivarizonaojs |
language |
English |
topic |
ejecta deposition;magnetic properties;K-T boundary;impact markers |
spellingShingle |
ejecta deposition;magnetic properties;K-T boundary;impact markers VILLASANTE-MARCOS, V. MARTNEZ-RUIZ, F. OSETE, M. L. URRUTIA-FUCUGAUCHI, J. Magnetic characterization of Cretaceous-Tertiary boundary sediments |
topic_facet |
ejecta deposition;magnetic properties;K-T boundary;impact markers |
description |
Rock magnetic properties across several K-T boundary sections have been investigated to reveal any possible magnetic signature associated with the remains of the impact event at the end of the Cretaceous. Studied sections locations vary in distance to the Chicxulub structure from distal (Agost and Caravaca, Spain), through closer (ODP Hole 1049A, Blake Nose, North Atlantic), to proximal (El Mimbral and La Lajilla, Mexico). A clear magnetic signature is associated with the fireball layer in the most distal sections, consisting of a sharp increase in susceptibility and saturation isothermal remanent magnetization (SIRM), and a decrease in remanence coercivity. Magnetic properties in these sections point to a distinctive ferrimagnetic phase, probably corresponding to the reported Mg- and Ni-rich, highly oxidized spinels of meteoritic origin. At closer and proximal sections magnetic properties are different. Although there is an increase in susceptibility and SIRM associated with a rusty layer placed on top of the siliciclastic deposit in proximal sections, and with a similar limonitic layer on top of the spherule bed that defines the boundary at Blake Nose, the magnetic properties indicate a mixture of iron oxyhydroxides dominated by fine-grained goethite. Based on previous geochemical studies at Blake Nose and new geochemical and PGE abundance measurements performed in this work at El Mimbral, this goethite-rich layer can be interpreted as an effect of diagenetic remobilization and precipitation of Fe. There is not enough evidence to assert that this Fe concentration layer at proximal sections is directly related to deposition of fine meteoritic material. Magnetic, geochemical, and iridium data reject it as a primary meteoritic phase. |
format |
Article in Journal/Newspaper |
author |
VILLASANTE-MARCOS, V. MARTNEZ-RUIZ, F. OSETE, M. L. URRUTIA-FUCUGAUCHI, J. |
author_facet |
VILLASANTE-MARCOS, V. MARTNEZ-RUIZ, F. OSETE, M. L. URRUTIA-FUCUGAUCHI, J. |
author_sort |
VILLASANTE-MARCOS, V. |
title |
Magnetic characterization of Cretaceous-Tertiary boundary sediments |
title_short |
Magnetic characterization of Cretaceous-Tertiary boundary sediments |
title_full |
Magnetic characterization of Cretaceous-Tertiary boundary sediments |
title_fullStr |
Magnetic characterization of Cretaceous-Tertiary boundary sediments |
title_full_unstemmed |
Magnetic characterization of Cretaceous-Tertiary boundary sediments |
title_sort |
magnetic characterization of cretaceous-tertiary boundary sediments |
publisher |
Meteoritics & Planetary Science Archives |
publishDate |
2007 |
url |
https://journals.uair.arizona.edu/index.php/maps/article/view/15484 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
Meteoritics & Planetary Science Archives; Vol 42, No 9 (2007); 1505-1527 1945-5100 1086-9379 |
op_relation |
https://journals.uair.arizona.edu/index.php/maps/article/view/15484/15472 https://journals.uair.arizona.edu/index.php/maps/article/view/15484 |
_version_ |
1766134369905278976 |