Evidence for Wave Propagation in the Holocene Palaeomagnetic Field

摘要: Analysis of Holocene lake sediment palaeomagnetic records to 13,000 years BP from nine sites on four continents reveals that prominent 1000–4000 year oscillations in declination and inclination can ‘be modelled as propagating wave-like disturbances superimposed an axial dipole field. Single site modelling cross-correlation analyses among intracontinental yield apparent propagation directions with poleward components both hemispheres, phase speeds the range 0.03–0.06°/yr. We present results numerical calculations non-linear α2 ω-dynamos, which exhibit principal features inferred data, including quadrupolar dynamo waves coexisting a dc dipolar