Abstract

Localities and deposits in north-west Nûgssuaq yielding fossil corals of the order Scleractinia are described. The age of the corals is Campanian?, Maastrichtian and Lower Paleocene (Danian), on the basis of other marine fossils. 22 species are considered; 7 are described as new and are indigenous, 2 are possibly North American forms, 3 are known from Europe, and 10 are identifiable only to generic level. The following genera and subgenera are represented: Haimesiastraea (Haimesiastraea), H. (Perupiastrea)?, Discotrochus?, Astrangia (Coenangia)?, Oculina, Caryophyllia, Trochocyathus, Paracyathus, Stephanocyathus (Stephanocyathus), Desmophyllum?, Lophelia?, Parasmilia, Flabellum, Balanophyllia, and Dendrophyllia . In addition, two new genera are described: Kangiliacyathus and Faksephyllia . Certain Danian corals from Scandinavia are also revised. In a survey of habitats, the lithology of the corallocalities is considered together with bathymetric and thermal ranges known for scleractinian genera and species from other parts of the world. Depth and temperature of the Campanian and Maastrichtian seas in Greenland cannot be estimated with any accuracy. The Lower and Upper Danian seas were generally rather shallow. There is little evidence on which to judge the Danian climate. Two species were perhaps hermatypic (no reef structures have been found). The remaining scleractinians are presumed to have been ahermatypic. A non-reef coral association has been found. Lower Danian rather sparsely populated polytypic coral thickets show signs of continual disturbance from water turbulence. The approximate depth of formation of these thickets appears to have been 80 m or shallower, which appears to be less than is usual for coral structures of this type. Some Lower Paleocene species provide conclusive evidence of a direct connection between the Danian seas of West Greenland and of Scandinavia.

Highlights

  • I n Greenland, scleractinian corals of Upper Cretaceous and Lower Tertiary age have so far been found only in West Greenland

  • Scleractinian fossils were noticed on Nugssuaq for the first time by the Danish Nugssuaq Expeditions (De Danske Nugssuaq Ekspeditioner) 1938-39, which were led by Professor ALFRED ROSENKRANTZ, Copenhagen

  • With rich occurrence of Dendrophyllia the above-mentioned Danian apparently rather shallow structures remind of Dendrophyllia structures on depths from 80 m and more, in the warm sea off Morocco. Another possibIe parallel may be found in the Dendrophyllia-rich Holocene structures on the Niger Delta (ALLEN & WELLS, 1962; SQUIRES; and New Zealand (SQUIRES), 1964)-2 or 3 genera of scleractinians are common to Tuff II and to the Niger structures, and Dendrophyllia and Cyathoceras are common to the Niger structures and to the bank complex of Fakse

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Summary

INTRODUCTION

I n Greenland, scleractinian corals of Upper Cretaceous and Lower Tertiary age have so far been found only in West Greenland. One undeterminable specimen was found in a displaced calcareous concretion in the big gorge to the north of Koralkløft (Fig. 10); its age is probably Lower Danian. Remarks on the species in Europe (history, identifications, recent revision) : There is no serious doubt that material of the present species, from Fakse limestone quarry in Denmark (Middle Danian), was considered by JOHNSTRUP, in 1864 It was observed how the corallites have no internal communication between their endothecal regions but it was not considered to what extent this was due to the way of budding or to internal filling up with stereome. Both the old material and the new were described It cannot be demonstrated why NIELSEN (1919,1922) changed the generic identification and placed the species in Amphelia EDWARDS & HAIME, 1849 a (Amphihelia EDWARDS & HAIME, 1857; by NIELSEN spelled Amphihelia and Amfihelia), which is considered a synonym to Madrepora LINNE, 1758

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Summary of localities with theil
Findings
København
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