Presencia de Girvanella y trazas fósiles en los ironstones ordovícicos y metasediméritos encajantes de la provincia de Zamora (España)

Abstract

The paleobiostratigraphic characteristics o f the Ordovician ironstones and the Lower Ordovician metasediments of the Zamora province are described in this paper. Futhermore a paleogeography reconstruction of these rocks is maked. It's important the presence of Girvanella Problematica and Redonia in the ironstones as soon as numerous fossil traces: Daedalus halli and Cruclana which are associated to the Lower Ordovician metasediments (infra-Arenig and Arenig). These relics determine as hallow marine environment in the formation of this materials. This environment is in te grated in a extensive platform which is situated in the N margin of the Condwana continent