Gondwana events and palaeogeography: a palaeomagnetic review

Several important tectonic episodes stand out in Gondwana's major and micro plate motions: (1) Gondwana assembly; (2) the general movement of Gondwana towards higher latitudes in the Palaeozoic; (3) the influence of terranes o n Gondwana Mesozoic break-up motions; and (4) Mesozoic-Cenozoic terrane mot ion along Gondwana's convergent margins. Current palaeomagnetic data indica te that the various fragments of Gondwana were assembled between similar to 900 and similar to 500 Ma. After assembly, the East Gondwana portion of Go ndwana moved from more equatorial latitudes in the Early Palaeozoic into mu ch higher latitudes by the Late Palaeozoic, whereas that of West Gondwana w as the opposite. This overall motion and concomitant climatic change had a profound influence on the palaeoevolution of different Gondwana faunas and floras in the Palaeozoic. During the Palaeozoic and Mesozoic, convergence a long the Gondwana margin resulted in accretion of various microplates. By t he Early to Mid-Jurassic, palaeomagnetic data suggest that terrane motion a long the palaeo-Pacific margin of Gondwana was related to the initial break -up of the supercontinent. This motion, especially in West Antarctica and N ew Zealand, caused the intermittent occurrence of palaeoseaways and landbri dges between East and West Gondwana. In the Tertiary, collision of India an d Africa with Eurasia caused significant local rotations associated with re gional deformation. ((C)) 1999 Elsevier Science Limited. All rights reserve d.