Open AccessSilurian biostratigraphy: revision of the North Atlantic Realm in the Llandovery
Author(s) -
A. J. Boucot,
John M. Hurst
Publication year - 1979
Publication title -
rapport
Language(s) - English
Resource type - Journals
eISSN - 2597-2944
pISSN - 0418-6559
DOI - 10.34194/rapggu.v91.7620
Subject(s) - biostratigraphy , paleontology , ordovician , geology , devonian , fauna , biology , ecology
Llandovery faunas have been considered more cosmopolitan than any others during the Lower Ordovician - Middle Devonian with only two undivided biogeographic Realms, the North Atlantic and Malvinokaffric, being recognised. Endemie pentameroids known from the Ashgill - Middle Llandovery of the Uralian region, Siberian Platform and adjacent Sette Daban occur commonly in North Greenland. Thus, during this time and in biofacies rich in pentameroids, the North Atlantic Realm appears divisible into a North Atlantic Region and a Uralian-Cordilleran Region, as in the Upper Silurian.