The Kimmeridgian ammonite faunas of Milne Land, central East Greenland

Abstract

Extensive new collections of ammonites made bed by bed in many sections through the Kimmeridgian (Lower Kimmeridgian sensu anglico) of Milne Land are described. These are used to revise and amplify the earlier accounts in a classical monograph of 1935 by Spath. The ammonites occur at ten sharply defined and well separated faunal horizons in the Bays Elv, Cardioceraskløft and Gråkløft Members of the Kap Leslie Formation. These horizons are readily correlated with the well-known successions of NW Europe, and their precise stratigraphical positions within the framework of the standard NW European Sub-Boreal zonation are discussed. All five Zones – Baylei, Cymodoce, Mutabilis, Eudoxus and Autissiodorensis – are represented. The more tenuous correlations with the analogous successions of the Barents Shelf and northern Siberia are also discussed. The faunas belong almost wholly to the two Sub-Boreal families Cardioceratidae and Aulacostephanidae. In the former, eight species of Amoeboceras are described, one of them new: A. (Amoebites) bayi sp. nov., closely related to European A. (A.) bauhini . In the latter family ten species of the genera Pictonia, Rasenia, Pachypictonia?, Aulacostephanoides and Aulacostephanus are described. Those of Pictonia and Rasenia are particularly significant in comparison with European and Siberian forms. Other families continue to be represented by but a single specimen of the Oppeliidae, Streblites? cf. S. taimyrensis Mesezhnikov. Some key sections of stratigraphical importance are recorded in an Appendix.