The eocrinoid Ascocystites Barrande (Echinodermata, Blastozoa) from the Middle Ordovician of central Portugal, with comments on the stratigraphy of the Brejo Fundeiro Formation

Authors

  • Timothy P. Young Department of Geology, University of Wales College of Cardiff
  • Stephen K. Donovan Department of Geology, University of the West Indies, Mona, Kingston 7, Jamaica

DOI:

https://doi.org/10.4138/1997

Abstract

The eocrinoid Ascocystites is recorded from the Middle Ordovician (Lower Llanvirn) Brejo Fundeiro Formation of the Domes region, central Portugal. The Brejo Fundeiro Formation is a sequence of mudrocks overlying the "Armorican Quartzite" (Lower Ordovician, Arenig). Ascocystites was found in a decalcified concretion from a horizon close to the base of the formation. This genus has previously been recorded only from the Middle Ordovician of Bohemia and the Armorican Massif. All occurrences lie within the Gondwanan West European Platform. RÉSUMÉ L'éocrinoide Ascocystites est reconnu dans la Formation de Brejo Fundeiro de l'Ordovicien moyen (Llanvirn inférieur) de la région de Dames, dans le centre du Portugal. La Formation de Brejo Fundeiro est une séquence de mudrocks recouvrant la "Quartzite Armoricaine" (Ordovicien inférieur, Arenig). Ascocystites fut trouvé dans une concrétion décalcifiée d'un horizon près de la base de la formation. Ce genre était auparavant connu seulement de l'Ordovicien moyen de la Bohème et du massif armoricain. Toutes les occurences se situent dans la plate-forme de Gondwana de l'Europe de l'ouest. [Traduit par la rédaction]

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Published

1993-07-01

How to Cite

Young, T. P., & Donovan, S. K. (1993). The eocrinoid Ascocystites Barrande (Echinodermata, Blastozoa) from the Middle Ordovician of central Portugal, with comments on the stratigraphy of the Brejo Fundeiro Formation. Atlantic Geoscience, 29(2). https://doi.org/10.4138/1997

Issue

Vol. 29 No. 2 (1993)

Section

Articles

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