Global and regional assessments of paleosecular variation activity over the past 100 ka

TitleGlobal and regional assessments of paleosecular variation activity over the past 100 ka
Publication TypeJournal Article
Year of Publication2018
AuthorsPanovska S., Constable C.G, Brown M.C
JournalGeochemistry Geophysics Geosystems
Date Published2018/05
Type of ArticleArticle
ISBN Number1525-2027
Accession NumberWOS:000436542200009
Keywordsantarctic south atlantic; archeomagnetic data; correlation; excursion; Geochemistry & Geophysics; geomagnetic excursion; geomagnetic secular variation; high-resolution record; inter-hemispheric; Laschamp; late; late quaternary sediments; magnetization lock-in; mono lake excursion; ocean drilling program; pacific; paleomagnetic secular variation; paleomagnetic sediment data; Quaternary; relative paleointensity data; western equatorial

We present a global compilation of paleomagnetic data spanning the past 100 ka. Sediment data comprise 61,687 declinations, 70,936 inclinations, and 69,596 relative paleointensities. Many sites are located in the northern Atlantic and western Pacific, with approximately twice as many data from the Northern Hemisphere as from the Southern Hemisphere. The 14,954 volcanic and archeomagnetic data are sparse, especially in the Southern Hemisphere. Directional and intensity information are aggregated under the paleosecular variation (PSV) index to assess occurrence of excursions over the past 100 ka. The Laschamp excursion (approximate to 41 ka) is clearly defined across globally distributed sediment records with an average duration of 1,300 years. Regional stacks obtained using bootstrap resampling show a more pronounced Laschamp excursion in the Northern Hemisphere than in the Southern, and in the Atlantic Hemisphere compared with the Pacific. No anomalous indices occurred around the Mono Lake excursion or other periods in the bootstrap curves. This may result from low sedimentation rates, discrepancies in age scales, large age errors, and/or the lack of global character of any transitional events. These data and associated new uncertainty estimates for the sediment records provide a good foundation for global, time-dependent, spherical harmonic field modeling for the past 100 ka.

Short TitleGeochem. Geophys. Geosyst.
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