The stratigraphy of the Upper Jurassic and Lower Cretaceous sediments of Milne Land, central East Greenland

Abstract

The upper part of the jurassic to Lower Cretaceous succession of Milne Land, described in the present paper, represents an unusually complete, highly fossiliferous sequence of Kimmeridgian, Lower and Middle Volgian and poorly fossiliferous ?Lower Valanginian to Hauterivian deposits. On the basis of some 50 recorded sections the succession is described with respect to lithology and fossil content and placed within a lithostratigraphical frarnework. The Upper Callovian – Middle Volgian Kap Leslie Formation (overlying the Charcot Bugt Formation) is divided into eight members, the upper four of which are described in detail (Gråkløft Member, Krebsedal Member, Pernaryggen Member and Astartedal Member), while the Middle Volgian – Hauterivian Hartz Fjeld Formation above is divided into two members (Hennigryggen Member and Pinnadal Member). A succession of 34 ammonite faunas has been recorded from the Kimmeridgian to Middle Volgian succession of the area. The Kimmeridgian to Lower Volgian faunas match British faunas so closely that the standard zonation of Great Britain can be used. The 17 faunas of the Middle Volgian are closer to successions of northern Russia and Siberia, and the succession has been made the basis of a new regional zonation of nine standard zones for the Boreal Province. One Lower Cretaceous ammonite fauna has been recorded, having ?Early Valanginian age and uncertain affinities. The faunal horizons of Volgian ammonites from Milne Land figured by Spath (1936) in his classical monograph have been determined. Stratigraphically important species found since then have been described elsewhere (Callomon & Birkelund, 1982). The three main areas of outcrops, the Hartz Fjeld area, the Kronen area and the Bays Fjelde area, are correlated in detail on the basis of ammonite occurrences. The depositional environments and tectonic evolution of the Milne Land area are outlined. Some key sections of particular stratigraphical importance are described in an appendix.