Swiss Journal of Geosciences

, Volume 104, Issue 1, pp 81–96

The Pliensbachian ammonites of the Algarve Basin (Portugal) and their palaeobiogeographical significance for the “Iberia-Newfoundland” conjugate margins

Authors

    • Université de Bourgogne, Biogeosciences, UMR CNRS 5561
  • Christian Meister
    • Département de Géologie et de PaléontologieMuséum d’Histoire naturelle de Genève
  • Rogério B. Rocha
    • Earth Sciences Department, Faculty of Sciences and Technology, Geological Sciences and Engineering Research CenterUniversidade Nova de Lisboa
Article

DOI: 10.1007/s00015-011-0056-2

Cite this article as:
Dommergues, J., Meister, C. & Rocha, R.B. Swiss J Geosci (2011) 104: 81. doi:10.1007/s00015-011-0056-2

Abstract

A review of the Pliensbachian ammonite faunas of the Algarve Basin is given covering their taxonomy, stratigraphy and palaeobiogeography (palaeobiodiversity). This review is based on both an extensive revision of the previously collected and/or published material and on new finds precisely located within the ammonite succession. This new material allows us to clarify the variations within the most abundant species—a new species Reynesocoeloceras elmii nov. sp. is described—and to improve our understanding (palaeobiodiversity, palaeobiogeography and bio- or chrono-stratigraphy) of the two single known Pliensbachian fossiliferous assemblages in the Algarve Basin. The first of these assemblages is relatively diverse and is ascribed to the upper half of the Luridum Subchronozone. The second assemblage is less diversified and probably partly condensed. It is broadly attributed to the upper half of the Stokesi Subchronozone. Despite the newly collected ammonites and extensive prospecting, our knowledge of the Pliensbachian ammonite faunas of the Algarve remains fragmentary. Therefore, it is difficult to propose an incontrovertible extensive palaeobiogeographical interpretation for these faunas, but it seems that Tethyan (Mediterranean) affinities were of major importance whereas there were probably no NW European influences via the Lusitanian Basin.

Keywords

Ammonites Early Jurassic Algarve Basin Portugal Stratigraphy Palaeobiogeography

Institutional abbreviations

BEL

Forte de Belixe, specimen housed in the collections of the “Universidade Nova de Lisboa” (R.B. Rocha collection)

CSV

Cabo de Sao Vicente, specimen housed in the collections of the “Universidade Nova de Lisboa” (R.B. Rocha collection)

SGP

Specimen housed in the Collections of the “Serviços Geológicos de Portugal” (P. Choffat collection)

UBGD

Specimen housed in the collections of the “Université de Bourgogne, Géologie Dijon”

Copyright information

© Swiss Geological Society 2011