Phanerozoic palaeogeography and geodynamics with Atlantic details

Abstract

In this report we synthesize palaeogeographic reconstructions over the last 500 million years. These reconstructions are global and should be regarded as first-order approximations. Reconstructions are essentially derived from 5 sources: (1) palaeomagnetic data, (2) magnetic anomaly data, (3) hot spot tracks, (4) biogeographic-tectonic data and (5) continental 'coast-line' fitting. Palaeomagnetic data provide quantitative information on palaeolatitude and palaeo-rotation of a continent, while palaeolongitude is unconstrained. The Palaeozoic reconstructions are essentially grounded in palaeomagnetic data combined with biogeographic-tectonic data. The Late Palaeozoic to Early-Mid Mesozoic reconstructions are based on a combi- nation of palaeomagnetic, magnetic anomaly data and 'coast-line fits. Finally, Cretaceous and younger reconstructions (130-10.5 Ma) are 'absolute' reconstruc- tions in a hot-spot\/magnetic anomaly reference scheme. The latter reconstruc- tions rely on the assumption that hot-spots are stationary or move at rates that are insignificant compared with plate-tectonic movements. Data analyses, reconstructions and most figures were produced with the GMAP software of Torsvik & Smethurst (1998) which is located on http:\/\/www.ngu.no\/ geophysics or http:\/\/dragon.ngu.no.