Data/hora: 03/06/2024 08:06:21

Provedor de dados: | Institutional Archive of Ifreme (ArchiMer)
País: | France
Título: | Authigenic 10Be/9Be ratio signatures of the cosmogenic nuclide production linked to geomagnetic dipole moment variation since the Brunhes/Matuyama boundary
Autores: | Simon, Quentin; Thouveny, Nicolas; Bourles, Didier L.; Valet, Jean-pierre; Bassinot, Franck; Menabreaz, Lucie; Guillou, Valery; Choy, Sandrine; Beaufort, Luc.
Data: | 2016-11
Ano: | 2016
Resumo: | Geomagnetic dipole moment variations associated with polarity reversals and excursions are expressed by large changes of the cosmogenic nuclide beryllium-10 (10Be) production rates. Authigenic 10Be/9Be ratios (proxy of atmospheric 10Be production) from oceanic cores therefore complete the classical information derived from relative paleointensity (RPI) records. This study presents new authigenic 10Be/9Be ratio results obtained from cores MD05-2920 and MD05-2930 collected in the west equatorial Pacific Ocean. Be ratios from cores MD05-2920, MD05-2930 and MD90-0961 have been stacked and averaged. Variations of the authigenic 10Be/9Be ratio are analyzed and compared with the geomagnetic dipole low series reported from global RPI stacks. The largest 10Be overproduction episodes are related to dipole field collapses (below a threshold of 2 × 1022 Am2) associated with the Brunhes/Matuyama reversal, the Laschamp (41 ka) excursion, and the Iceland Basin event (190 ka). Other significant 10Be production peaks are correlated to geomagnetic excursions reported in literature. The record was then calibrated by using absolute dipole moment values drawn from the Geomagia and Pint paleointensity value databases. The 10Be-derived geomagnetic dipole moment record, independent from sedimentary paleomagnetic data, covers the Brunhes-Matuyama transition and the whole Brunhes Chron. It provides new and complementary data on the amplitude and timing of millennial-scale geomagnetic dipole moment variations and particularly on dipole moment collapses triggering polarity instabilities.
Tipo: | Text
Idioma: | Inglês

Identificador:

https://archimer.ifremer.fr/doc/00358/46910/46811.pdf

https://archimer.ifremer.fr/doc/00358/46910/46814.pdf

https://archimer.ifremer.fr/doc/00358/46910/46815.pdf

https://archimer.ifremer.fr/doc/00358/46910/46816.csv

DOI:10.1002/2016JB013335

https://archimer.ifremer.fr/doc/00358/46910/

Editor: | Amer Geophysical Union
Relação: | info:eu-repo/grantAgreement/EC/FP7/339899/EU//EDIFICE
Formato: | application/pdf
Fonte: | Journal Of Geophysical Research-solid Earth (2169-9313) (Amer Geophysical Union), 2016-11 , Vol. 121 , N. 11 , P. 7716-7741

Fonte:

2016. The Authors. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

info:eu-repo/semantics/openAccess

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