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High palaeolatitude (Hodh, Mauritania) recovery of graptolite faunas after the Hirnantian (end Ordovician) extinction event

By Charlie J. Underwood, M. Deynoux and J.F. Ghienne

Abstract

Marine shales directly overlying lower Hirnantian (uppermost Ordovician) glacially related sediments in Mauritania (North-West Africa) have produced a rich graptolite fauna spanning the Ordovician-Silurian boundary in an area of high palaeolatitude. The lowermost transgressive sandy shales are barren of graptolites, but overlying shales show a sudden appearance of a diverse fauna indicative of the terminal Ordovician persculptus Zone, suggesting that with improving conditions, colonisation by a relatively cold-tolerant fauna was possible. This fauna is replaced by a low diversity assemblage dominated by long ranging taxa, probably representing the basal Silurian acuminatus and atavus Zones. With the extinction of the persculptus Zone fauna, conditions were still hostile to warm water Silurian graptolites, and a Normalograptus fauna was again established. A sudden influx of fairly diverse taxa marks the base of the acinaces Zone and the establishment of a typical Lower Silurian fauna with the establishment of warmer water conditions

Topics: es
Publisher: Elsevier
OAI identifier: oai:eprints.bbk.ac.uk.oai2:108

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Citations

  1. (1988). A Global analysis of the Ordovician-Silurian Boundary.
  2. (1993). Ashgillian graptolites of the Chirfa region (Djado,
  3. (1994). Bathymetric and isotopic evidence for a short-lived Late Ordovician glaciation in a greenhouse period. doi
  4. (1997). Carbon Isotopic events associated with mass extinction and glaciation in the late Ordovician. doi
  5. (1995). Chitnozoans and Late Ordovician glacial events on Gondwana.
  6. (1948). Deep boring through Ordovician and Silurian strata at Kinnekulle, doi
  7. (1996). Diachronous recovery patterns in early Silurian corals, graptolites and acritarchs. doi
  8. Early Silurian graptolites from Southeastern Alaska and their correlation with graptolitic sequences
  9. (1988). Environmental changes close to the Ordovician-Silurian boundary. doi
  10. (1987). Evolution and phylogenetic classification of the Diplograptacea.
  11. (1977). Evolution of the Silurian and Devonian graptoloids. doi
  12. (1990). Graptolite biogeography: implications for palaeogeography and palaeoceanography. doi
  13. (1988). Graptolite faunas at the base of the Silurian. doi
  14. (1991). Late Ordovician extinction of the Graptoloidea. doi
  15. (1984). Late Ordovician extinctions and their relationship to the Gondwana glaciation.
  16. (1991). Late Ordovician stratigraphy, paleoecology and sea-level changes in the Argentine Precordillera. doi
  17. (1970). Les crouches a Diplograptus du Tassili de Tarit (Ahnet, Sahara algerien).
  18. (1980). Les formations glaciaires du Precambrian terminal et de la fin de l'Ordovicien en Afrique de l'ouest.
  19. (1985). Lower Palaeozoic of West Africa and the Western part of Central Africa.
  20. (1981). Lower Palaeozoic rocks of southern Africa. doi
  21. (1985). Lower Paleozoic rocks of Morroco. In
  22. (1982). Mass extinctions in the marine fossil record. doi
  23. (1996). Models for biotic survival following mass extinction. doi
  24. (1929). Notes on the graptolite faunas of the Upper Ordovician and Lower Silurian. doi
  25. (1996). Ordovician and Silurian graptolite assemblages from Cerro del Fuerte, doi
  26. (1995). Patterns of change in the brachiopod faunas through the Ordovician-Silurian interface. doi
  27. (1990). Revised World maps and introduction. doi
  28. (1996). Taxonomy and evolution of Llandovery biserial graptoloids from the southern Urals,
  29. (1996). Taxonomy and evolution of Llandovery biserial graptoloids from the southern Urals, western Kazakhstan. Special Papers in
  30. (1985). Terrestrial or waterlain glacial diamictites? Three case studies from the Late Precambrian and Late Ordovician glacial drifts in West Africa. doi
  31. (1970). The evolution of the earliest Llandovery monograptids. doi
  32. (1996). The Hirnantian graptolites Normalograptus persculptus and 'Glyptograptus' bohemicus: stratigraphical consequences of their synonymy.
  33. (1996). The importance of crisis progenitors in recovery from mass extinctions. doi
  34. (1975). The Llandovery graptolites of the English Lake District.
  35. (1986). The Lower Silurian graptolites of Oued In Djerane: a study of populations at the Ordovician-Silurian boundary. doi
  36. (1995). The Ordovician radiations: diversification and extinction shown by global genus-level taxonomic data.
  37. (1983). The Ordovician-Silurian boundary graptolite fauna of Dob's Linn, southern Scotland. doi
  38. (1988). The Ordovician-Silurian boundary in
  39. (1988). The Ordovician-Silurian boundary in Mauritania.
  40. (1988). The Ordovician-Silurian boundary in Saudi Arabia.
  41. (1988). The Ordovician-Silurian boundary in the Algerian Sahara. doi
  42. (1988). The Ordovician-Silurian boundary in the Altai Mountains, doi
  43. (1986). Top Ordovician and lowest Silurian at Dob's Linn. doi
  44. (1990). Upper Ordovician glacial deposits in
  45. (1990). Upper Ordovician-lower Silurian sequences of the Bohemian Massif, central Europe. doi
  46. (1994). Uppermost Ordovician to lower Silurian graptolite biostratigraphy of the Wye Valley, central Wales.
  47. (1995). Utility and precision of Silurian graptolite biozones. doi

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