Les Ostracodes du Frasnien terminal (Zone à linguiformis des Conodontes) de la coupe du col de Devils Gate (Nevada, USA)Latest Frasnian (linguiformis conodont Zone) ostracods from the Devils Gate Pass section (Nevada, USA)
Casier, J.-G.; Lethiers, F. (1998). Les Ostracodes du Frasnien terminal (Zone à linguiformis des Conodontes) de la coupe du col de Devils Gate (Nevada, USA)
Latest Frasnian (linguiformis conodont Zone) ostracods from the Devils Gate Pass section (Nevada, USA). Bull. Kon. Belg. Inst. Natuurwet. Aardwet. = Bull. - Inst. r. sci. nat. Belg., Sci. Terre 68: 77-95
In: Bulletin van het Koninklijk Belgisch Instituut voor Natuurwetenschappen. Aardwetenschappen = Bulletin de l'Institut Royal des Sciences Naturelles de Belgique. Sciences de la Terre. KBIN: Brussel. ISSN 0374-6291, meer
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Trefwoorden |
Geological time > Phanerozoic > Paleozoic > Palaeozoic > Devonian Geological time > Phanerozoic > Paleozoic > Palaeozoic > Devonian > Devonian, Upper Geological time > Phanerozoic > Paleozoic > Palaeozoic > Devonian > Devonian, Upper > Frasnian Ostracoda [WoRMS] USA, Nevada [Marine Regions] Marien/Kust |
Author keywords |
Ostracods - Mass extinction - Late Frasnian - Devils Gate - Nevada, Ostracodes - Extinction en masse - Frasnien Supérieur |
Auteurs | | Top |
- Casier, J.-G., meer
- Lethiers, F.
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Abstract |
In relation with the study of the Late Devonian mass extinction, we present here the ostracods extracted from 15 samples collected in the linguiformis conodont Zone of the Devils Gate Pass section, in Nevada. Seventy ostracod species, the majority of which are figured, have been identified in the uppermost beds of the Frasnian of this section. The assemblage of ostracods is rich and diversified and belongs to the Eifelian ecotype which is emended to take the occurrence of Podocopida, occasionally in abundance, into account. It characterizes here a well oxygenated marine environment below wave base probably on the outer platform. Among the 70 species occurring in the uppermost beds of the Frasnian. 16 survive the Late Devonian mass extinction at Devils Gate or in other sections (=Lazarus species). No ostracod assemblage characteristic of oxygen depleted water conditions has been identified at Devils Gate. Such an assemblage rich in Entomozoacean and Cypridacean ostracods (= Myodocopid ecotype) occurs just below the Frasnian/Famennian boundary in several European sections. Thus probably anoxic water conditions could not alone explain the disappearance of about 80% of ostracods close the Frasnian/Famennian boundary on the West american craton. Five new species are erected: Amphissites sandbergi nov. sp., Kozlowskiella lazarei nov. sp., Bairdia (Rectobairdia) proximischimensis nov. sp., Bairdia (Rectobairdia) altodorsualis nov. sp. and Bairdia (Rectobairdia) pintoensis nov. sp. |
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