Intermittent non-axial dipolar-field dominance of twin Laschamp excursions

Abstract Geomagnetic excursions represent the dynamic nature of geodynamo. Accumulated palaeomagnetic records indicate that such are dominated by dipolar-fields, but exhibit different structures. Here we report a record from varved sediments Lake Suigetsu, central Japan, which reveals fine structures in Laschamp Excursion and new post-Laschamp excursion coincides with Δ 14 C maxima. The record’s high-resolution chronology provides IntCal20 mid-ages varve-counted durations. Both comprise multiple subcentennial directional-swings. Simulations filtering effects on sediment-magnetisations demonstrate this replicates most features existing, lower-resolution records, including apparent clockwise open-loop virtual geomagnetic pole pass. poles during ‘swing’ phases make four clusters centred hemispherically-symmetric regions, three encompass associated recorded lavas at various locations. stationary dipolar-field sources under each cluster should have intermittently one after another excursions.