Lower Jaramillo polarity transition records from ODP Holes 108-665A and 121-758B
Two records of the geomagnetic polarity transition at the beginning of the Jaramillo Subchron (0.97 Ma) have been obtained from sediments in the equatorial Atlantic (Leg 108, Site 665; 2.95°N, 340.33°E) and Indian (Leg 121, Site 758; 5.38°N, 90.35°E) oceans. Both cores yielded high-quality magnetost...
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.761128 2024-09-15T18:23:45+00:00 Lower Jaramillo polarity transition records from ODP Holes 108-665A and 121-758B Gee, Jeff S Tauxe, Lisa Barg, Eunjoo MEDIAN LATITUDE: 4.167600 * MEDIAN LONGITUDE: 35.346700 * SOUTH-BOUND LATITUDE: 2.951200 * WEST-BOUND LONGITUDE: -19.667800 * NORTH-BOUND LATITUDE: 5.384000 * EAST-BOUND LONGITUDE: 90.361200 * DATE/TIME START: 1986-04-03T21:00:00 * DATE/TIME END: 1988-06-15T15:58:00 1991 application/zip, 2 datasets https://doi.pangaea.de/10.1594/PANGAEA.761128 https://doi.org/10.1594/PANGAEA.761128 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.761128 https://doi.org/10.1594/PANGAEA.761128 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess Supplement to: Gee, Jeff S; Tauxe, Lisa; Barg, Eunjoo (1991): Lower Jaramillo polarity transition records from the equatorial Atlantic and Indian Oceans. In: Weissel, J; Peirce, J; Taylor, E; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 121, 377-391, https://doi.org/10.2973/odp.proc.sr.121.152.1991 108-665A 121-758B DRILL Drilling/drill rig Indian Ocean Joides Resolution Leg108 Leg121 North Atlantic Ocean Ocean Drilling Program ODP dataset publication series 1991 ftpangaea https://doi.org/10.1594/PANGAEA.76112810.2973/odp.proc.sr.121.152.1991 2024-08-21T00:02:25Z Two records of the geomagnetic polarity transition at the beginning of the Jaramillo Subchron (0.97 Ma) have been obtained from sediments in the equatorial Atlantic (Leg 108, Site 665; 2.95°N, 340.33°E) and Indian (Leg 121, Site 758; 5.38°N, 90.35°E) oceans. Both cores yielded high-quality magnetostratigraphic results; however, the relatively low sedimentation rates, the weak magnetizations, and complex demagnetization behavior of some transitional samples suggest that the record of the transitional field behavior may be less reliable. In addition, variations in grain size preclude reliable paleointensity determinations although the remanence in both cores is apparently dominated by magnetite. Despite these possible complications, the two cores yield transitional paths that are neither far-sided nor near-sided. Together with published records that meet minimum reliability standards, the two equatorial records presented here suggest that the lower Jaramillo transitional field morphology was significantly nonaxisymmetric. The mean normal and reversed inclinations from both cores deviate from the inclination expected from a geocentric axial dipole, as noted in virtually all marine sediment cores. The observed inclinations provide further support for a polarity-dependent nondipole contribution to the time-averaged field. Other/Unknown Material North Atlantic PANGAEA - Data Publisher for Earth & Environmental Science ENVELOPE(-19.667800,90.361200,5.384000,2.951200) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
108-665A 121-758B DRILL Drilling/drill rig Indian Ocean Joides Resolution Leg108 Leg121 North Atlantic Ocean Ocean Drilling Program ODP |
spellingShingle |
108-665A 121-758B DRILL Drilling/drill rig Indian Ocean Joides Resolution Leg108 Leg121 North Atlantic Ocean Ocean Drilling Program ODP Gee, Jeff S Tauxe, Lisa Barg, Eunjoo Lower Jaramillo polarity transition records from ODP Holes 108-665A and 121-758B |
topic_facet |
108-665A 121-758B DRILL Drilling/drill rig Indian Ocean Joides Resolution Leg108 Leg121 North Atlantic Ocean Ocean Drilling Program ODP |
description |
Two records of the geomagnetic polarity transition at the beginning of the Jaramillo Subchron (0.97 Ma) have been obtained from sediments in the equatorial Atlantic (Leg 108, Site 665; 2.95°N, 340.33°E) and Indian (Leg 121, Site 758; 5.38°N, 90.35°E) oceans. Both cores yielded high-quality magnetostratigraphic results; however, the relatively low sedimentation rates, the weak magnetizations, and complex demagnetization behavior of some transitional samples suggest that the record of the transitional field behavior may be less reliable. In addition, variations in grain size preclude reliable paleointensity determinations although the remanence in both cores is apparently dominated by magnetite. Despite these possible complications, the two cores yield transitional paths that are neither far-sided nor near-sided. Together with published records that meet minimum reliability standards, the two equatorial records presented here suggest that the lower Jaramillo transitional field morphology was significantly nonaxisymmetric. The mean normal and reversed inclinations from both cores deviate from the inclination expected from a geocentric axial dipole, as noted in virtually all marine sediment cores. The observed inclinations provide further support for a polarity-dependent nondipole contribution to the time-averaged field. |
format |
Other/Unknown Material |
author |
Gee, Jeff S Tauxe, Lisa Barg, Eunjoo |
author_facet |
Gee, Jeff S Tauxe, Lisa Barg, Eunjoo |
author_sort |
Gee, Jeff S |
title |
Lower Jaramillo polarity transition records from ODP Holes 108-665A and 121-758B |
title_short |
Lower Jaramillo polarity transition records from ODP Holes 108-665A and 121-758B |
title_full |
Lower Jaramillo polarity transition records from ODP Holes 108-665A and 121-758B |
title_fullStr |
Lower Jaramillo polarity transition records from ODP Holes 108-665A and 121-758B |
title_full_unstemmed |
Lower Jaramillo polarity transition records from ODP Holes 108-665A and 121-758B |
title_sort |
lower jaramillo polarity transition records from odp holes 108-665a and 121-758b |
publisher |
PANGAEA |
publishDate |
1991 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.761128 https://doi.org/10.1594/PANGAEA.761128 |
op_coverage |
MEDIAN LATITUDE: 4.167600 * MEDIAN LONGITUDE: 35.346700 * SOUTH-BOUND LATITUDE: 2.951200 * WEST-BOUND LONGITUDE: -19.667800 * NORTH-BOUND LATITUDE: 5.384000 * EAST-BOUND LONGITUDE: 90.361200 * DATE/TIME START: 1986-04-03T21:00:00 * DATE/TIME END: 1988-06-15T15:58:00 |
long_lat |
ENVELOPE(-19.667800,90.361200,5.384000,2.951200) |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
Supplement to: Gee, Jeff S; Tauxe, Lisa; Barg, Eunjoo (1991): Lower Jaramillo polarity transition records from the equatorial Atlantic and Indian Oceans. In: Weissel, J; Peirce, J; Taylor, E; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 121, 377-391, https://doi.org/10.2973/odp.proc.sr.121.152.1991 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.761128 https://doi.org/10.1594/PANGAEA.761128 |
op_rights |
CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1594/PANGAEA.76112810.2973/odp.proc.sr.121.152.1991 |
_version_ |
1810464021582708736 |