Paleogeographic Synthesis

Abstract

The paleogeographic reconstructions that have been proposed for the Paleozoic generally agree upon the existence of two major distinct paleogeographic units in Europe: Baltica and North Gondwana, separated by a mid-European Rheic Ocean. The evolution of this ocean, from its opening in the earliest Paleozoic until its closure during the Carboniferous, influenced the geological development of the entire Armorican Massif and more generally that of southwestern Europe. This evolution controlled: (1) the thick accumulation of sediments during the initial period of rifting and those which were possibly related to marginal accretionary prisms (Ardennes?); (2) the successive latitudinal positions of the distinct paleogeographic units and the resulting climatic conditions which influenced the distribution of facies and faunas; (3) the igneous activity, especially in relation with subduction zones; and (4) the tectonic and metamorphic processes when the ocean closed and the continents collided.