Increased production of cosmogenic 10Be recorded in oceanic sediment sequences: Information on the age, duration, and amplitude of the geomagnetic dipole moment minimum over the Matuyama–Brunhes transition
Type | Article |
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Date | 2018-05 |
Language | English |
Author(s) | Simon Quentin1, 2, Thouveny Nicolas1, Bourles Didier L.1, Bassinot Franck2, 3, 4, Savranskaia Tatiana2, Valet Jean-Pierre2 |
Affiliation(s) | 1 : Aix Marseille Univ, CEREGE UM34, CNRS, IRD,INRA,Coll France, Aix En Provence, France. 2 : Univ Paris Diderot, UMR CNRS 7154, Sorbonne Paris Cite, Inst Phys Globe Paris, Paris, France. 3 : CEA CNRS UVSQ, LSCE IPSL, UMR8212, LSCE, Gif Sur Yvette, France. 4 : Univ Paris Saclay, Gif Sur Yvette, France. |
Source | Earth And Planetary Science Letters (0012-821X) (Elsevier Science Bv), 2018-05 , Vol. 489 , P. 191-202 |
DOI | 10.1016/j.epsl.2018.02.036 |
WOS© Times Cited | 26 |
Keyword(s) | authigenic Be-10/Be-9 ratio, geomagnetic dipole moment minimum, Matuyama-Brunhes transition (MBT), geomagnetic polarity reversal, marine isotope stage 19, atmospheric Be-10 production rates |
Abstract | New high-resolution authigenic 10Be/9Be ratio (Be-ratio) records covering the last geomagnetic reversal, i.e. the Matuyama–Brunhes transition (MBT), have been obtained and set on a time scale using benthic δ18 O (Cibicides wuellerstorfi) records. The geographic distribution of the four studied sites allows global comparison between the North Atlantic, Indian and Pacific Oceans. All Be-ratio records contain a two-fold increase triggered by the geomagnetic dipole moment (GDM) collapse associated with the MBT. The stratigraphic position of the Be-ratio spike, relative to marine isotope stages, allows establishment of a robust astrochronological framework for the MBT, anchoring its age between 778 and 766 ka (average mid-peaks at 772 ka), which is consistent with all other available 10Be-proxy records from marine, ice and loess archives. The global 10Be atmospheric production doubling represents an increase of more than 300 atoms m−2 s−1 that is compatible with the increased magnitude of atmospheric 10Be production obtained by simulations between the present GDM and a null-GDM. The minimum 10Be-derived GDM average computed for the 776–771 ka interval is 1.7±0.4×10 22 Am2, in agreement with model simulations and absolute paleointensities of transitional lava flows. |
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