The Phillipsinella Parabola?Staurocephalus Clavifronsfauna and Upper Ordovician correlation
| Autor: | Price, D. |
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| Zdroj: | Geological Magazine; November 1973, Vol. 110 Issue: 6 p535-541, 7p |
| Abstrakt: | SummaryHorizons characterized by the trilobites Staurocephalus clavifronsand/or Phillipsinella parabolahave long been regarded as significant in Upper Ordovician correlation. From time to time this idea has been formalized by the erection of Phillipsinella parabolaor Staurocephalus clavifronsZones or by equating the range of a ?Phillipsinella parabolafauna? with Series sub-divisions within the Standard Ordovician succession. At the present time the Phillipsinella parabola-Staurocephalus clavifronsfauna is widely regarded as indicating a Rawtheyan age (Ashgill Zones 5?7).Recent work by the author, however, together with a review of available evidence from the literature casts grave doubts on the validity of such concepts. It is suggested that in some areas the Phillipsinella parabola-Staurocephalus clavifronsfauna may range at least as low as basal Cautleyan (Ashgill Zone 1). |
| Databáze: | Supplemental Index |
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