213 Harper et al.: Early Cretaceous brachiopods from North-East Greenland · Early Cretaceous brachiopods from North-East Greenland: Biofacies and biogeography DAVID A.T. HARPER, PETER ALSEN, ELLIS F. OWEN & MICHAEL R. SANDY Harper, D.A.T., Alsen, P., Owen, E.F. & Sandy, M.R. 2005-12-31: Early Cretaceous brachiopods from North-East Greenland: Biofacies and biogeography. Bulletin of the Geological Society of Denmark, Vol. 52, pp. 213–225. © 2005 by Geological Society of Denmark. ISSN 0011–6297. Augmentation and revision of the relatively diverse Valanginian brachiopod faunas from North- East Greenland confirm the existence of two mutually exclusive but broadly coeval assemblages, associated with two contrasting facies types. A Boreal, relatively shallow-water assemblage domi- nated by large terebratulids and ribbed rhynchonellids, including Cyrtothyris, Lamellaerhynchia and Praelongithyris characterizes the Falskebugt fauna. By contrast the Albrechts Bugt and Rødryggen fauna contains Tethyan elements, more typical of deeper water, including Lacunosella, Placothyris, Pygope and Rugitela. This early Cretaceous Out-of-Tethys migration confirms the early and persist- ent northward track of a proto Gulf Stream current. A new taxon, Placothyris kegeli, is described from the Albrechts Bugt and Rødryggen members of the Palnatokes Bjerg Formation. Key words: Brachiopods, Valanginian, palaeogeography, palaeoenvironments, North-East Greenland. Harper, D.A.T. [dharper@snm.ku.dk], Geological Museum, University of Copenhagen, Øster Voldgade 5-7, DK-1350 Copenhagen K, Denmark; Alsen, P. [petera@geol.ku.dk], Geological Institute, University of Co- penhagen, Øster Voldgade 10, DK-1350 Copenhagen K, Denmark; Owen, E.F., Department of Palaeontol- ogy, The Natural History Museum, Cromwell Road, London SW7, UK & Sandy, M.R. [Michael.Sandy @notes.udayton.edu], Department of Geology, University of Dayton, 300 College Park, Dayton, OH 45469- 2364, USA. Brachiopods were first reported from the Lower Cre- taceous rocks of North-East Greenland in the 1940s (Maync 1940, 1949) based on collections made by that author earlier in the late 1930s. Additional material was collected by Donovan (1955, 1957) in the early 1950s on Lauge Koch expeditions, which formed the basis for Owen’s (1976) description of the brachio- pods from the region. Owen (1976) updated the pre- vious, sparse brachiopod records of Muir-Wood (1953) and Donovan (1955, 1957) from Wollaston Forland and Traill Ø, respectively. The brachiopod fauna is particularly significant. The fauna occupies a key position, geographically, within the Boreal Prov- ince, situated at the northern apex of the opening North Atlantic. The region contains a relatively di- verse and varied brachiopod assemblage, recorded, to date, from two different facies types. Important is the apparent co-occurrence of elements of both the Boreal and Tethyan provinces within the region (Owen 1976). An assemblage of large terebratulids together with ribbed rhynchonellids characterizes coarse-grained, iron-stained limestones from the Wollaston Forland; this is a typical Boreal biofacies associated with shallow-water, high-energy environ- ments. Tethyan brachiopods, however, have been reported from fine-grained deeper-water limestone from Mols Bjerge on Traill Ø. The exotic occurrence of Tethyan taxa in the Cre- taceous of North-East Greenland has generated two competing models. Tethyan elements entered the re- gion along a proto Gulf Stream current or arrived from deep-water, cooler Tethyan biofacies by up- welling currents (Ager 1971, 1973; Sandy 1991). New collections from North-East Greenland, a modern palaeoenvironmental analysis of the succession (Sur- lyk 1978, 2003) and a statistical approach to global biogeographical patterns, provide an opportunity to discuss these models further. Geological Setting The thick succession of Upper Jurassic – Lower Cre- taceous rocks in North-East Greenland is dominat- ed by black mudstones deposited in an anoxic envi-