Brachiopoda of the Melville Island Group (Upper Devonian), Banks Island, N.W.T.

Abstract

ABSTRACT On northeastern Banks Island, N.W.T., a total of 3700 feet of late Devonian clastics are exposed. In the lower 2600 feet of section occur rich benthonic faunas consisting primarily of brachiopods, pelecypods and corals. Thirteen brachiopod species are illustrated. One genus, Retichonetes, has not been previously reported from the Arctic Islands. Of particular importance is the presence of the rhynchonelloid zone fossils, Ladogioides pax and Calvinaria albertensis, and recognition of the overlap in stratigraphic ranges of Eleutherokomma and Cyrtospirifer. Analysis of the brachiopod faunas yields an age of from earliest Frasnian (zone of Ladogioides pax = Waterways and basal Hay River Formations) to late Frasnian (zone of Calvinaria albertensis = lower Mount Hawk and Ireton formations).