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Abstract: Ophiomorpha irregulaire is a large and extremely rare trace fossil. The type section is in the Book Cliffs, Utah, USA. A second on-shore locality is reported here, in the Nuussuaq Basin of West Greenland. Both occurrences date from the Late Cretaceous. Other reports of O. irregulaire are restricted to two-dimensional sections in well cores and are mostly Jurassic in age. The West Greenland occurrence is in the Atane Formation in shallow marine clean sandstone. The two on-shore localities lie in the same biogeographical region, in connection with the Cretaceous Western Interior Seaway of North America. O. irregulaire is characterized by a sinuous, branched meander maze lying mostly within a single horizontal plane, probably not far beneath the seafloor. The burrow lining has remarkably elongate pellets that probably were emplaced by the burrower. In some cases, diagenetic compression may have deformed the lining pellets to produce their elongated shape. The muddy sediment comprising the lining is almost unrepresented in the clean sands of the substrate, and it was probably trapped from suspension during suspension-feeding activity. [Copyright &y& Elsevier]

The article presents several studies that examine the Jurassic sedimentary succession in North-East Greenland. These studies deal with stratigraphic and depositional aspects of the Middle-Upper Jurassic sediments from isolated and popular localities outside the main outcrop areas. In one study, the stratigraphic development of the Jurassic succession in south-east Traill Ø comprising the E-tilted Bjørnedal Block bounded to the west by the Vælddal Fault is explored. Another study examined the formation of the Bristol Elv Formation.

The article examines the Jurassic sedimentary successions of Denmark and East Greenland. In comparing the Jurassic succession of both regions, Denmark is limited to the subsurface with exposures on the island of Bornholm in the Baltic Sea while East Greenland is exposed extensively. In subdividing both regions into tectonostratigraphic packages, it reveals that the tectonic evolution and stratigraphic signals are similar but the timing of rift and lift transition is delayed in East Greenland.