Paleobiogeographic significance of Bashkirian (Pennsylvanian) rugose corals from northernmost Ellesmere Island, Arctic Canada
Institute of Geology, Adam Mickiewicz University, Maków Polnych 16, Pl 61-606 Poznań, Poland; jerzy@amu.edu.pl
Geological Survey of Canada, Calgary, 3303 - 33rd Street NW, Calgary, Alberta, T2L 2A7, Canada; wabamber@nrcan.gc.ca
Abstract
The oldest known Carboniferous rugose coral fauna in the Canadian Arctic Islands occurs on the northwestern margin of the Sverdrup Basin, in the Yelverton Inlet area of northern Ellesmere Island. It was collected from Bashkirian carbonates of the lower Nansen and Otto Fiord formations and includes representatives of the genera Dibunophyllum Thomson & Nicholson, Lonsdaleia McCoy, Palaeosmilia Milne-Edwards & Haime and ?Tizraia Said & Rodríguez. Such a combination of genera is unknown elsewhere above the Serpukhovian and in this sense it is unique in the world. It is typical, however, for coral faunas in the Upper Viséan of Europe, North Africa and China. In those areas, genera of this assemblage range into the Upper Serpukhovian and individual genera such as Dibunophyllum in the Donets Basin and Palaeosmilia in Northern Timan and Novaya Zemlya continue into the Lower Bashkirian. The Yelverton Inlet fauna shows limited similarity to Serpukhovian faunas of several other basins but differs from the Bashkirian faunas of those basins. It is remarkable because of its unusual taxonomic content, high stratigraphic position, and remote geographic location. Faunal comparisons suggest Novaya Zemlya as the most likely source for the Yelverton Inlet fauna. Northern Timan may qualify as another possible source when its Viséan to Bashkirian coral fauna is described in detail.