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Since 1976 more than 25,000 Arctic sediment samples have been processed for their palynological, nannofossil, or microfossil content at the Geological Survey of Greenland (GGU) and the Geological Survey of Denmark (DGU); both institutes are now merged into the Geological Survey of Denmark and Greenland (GEUS). The samples represent nearly all ages from the Neoproterozoic to the Neogene, though dominated by the Mesozoic. A large proportion of the samples were processed for palynomorphs. Up to ten slides have been produced for each palynological sample and usually one slide is produced for each nannofossil and microfossil sample, making the GEUS collection one of the largest Arctic slide collections with more than 200,000 slides. All type specimens and some specimens illustrated in publications listed here have been assigned MGUH numbers (Museum Geologica Universitas Hafniensis) and are housed in the type collection of the Geological Museum of the University of Copenhagen, now part of the Natural History Museum of Denmark.

The Wandel Sea Basin in eastern North Greenland comprises Upper Palaeozoic – Paleogene sediments. Most stratigraphic units are well dated but new palynological analyses of the 85–100 m thick succession at Kap Rigsdagen, North Greenland have revealed two stratigraphically significant dinoflagellate cyst assemblages which change the earlier age assignment of the succession. The lower assemblage suggests a late Barremian age for the sediments. These sediments and the underlying, coarse-grained sediments (barren of dinoflagellate cysts) show similarities to the upper Ladegårdsåen Formation in Peary Land, also of late Barremian age. Consequently, this part of the Kap Rigsdagen succession is herein referred to the Ladegårdsåen Formation. The upper part of the Kap Rigsdagen succession yielded a diverse dinoflagellate cyst assemblage dominated by reworked Lower and Upper Cretaceous species but includes Lower to Middle Eocene taxa. Alterbidinium ? aff. bicellulum is the only abundant Eocene species in these strata. This part of the succession is referred to the Thyra Ø Formation based on lithology and paralic depositional environment of Early to Middle Eocene age. Similar rich reworked Cretaceous dinoflagellate cyst assemblages in Paleogene deposits have previously been reported from North and East Greenland. In all cases, this magnitude of reworking responds to regional uplift events in connection with the North Atlantic break-up and sea-floor spreading.

An extensive seismic database covering an area of 100,000 km2 (38,610 mi2] and 16 wells are integrated to define a sequencestratigraphic framework for the Lower Cretaceous succession in the southwestern Barents Sea. Seven sequences (S0-S6) are defined, and the geometry, trajectory, and lateral variability of decompacted seismic clinoforms are described to elucidate the depositional history of the basin and to better understand coarsegrained sediment transport from the shelf to basin. Three different clinoform scales are recognized: (1) clinoform sets with 35-60 m (115-197 ft] height, interpreted as deltaic or shoreline clinoforms; [2] clinoform sets with 60-110 m (197-361 ft] height, interpreted as sediments prograding on a continental shelf; and (3] clinoforms with greater than 150 m (>492 ft] height, which represent shelfmargin clinoforms. Furthermore, clinoforms are grouped into two main progradation directions: (1) clinoforms prograded to the southeast in sequences 2-3, in the Fingerdjupet Subbasin and the western Bjarmeland platform, indicating a source of sediments located in the west-northwestern Barents Sea, and (2] clinoforms prograded to the southwest in sequences 1-6, in the eastern part of the Bjarmeland platform, Nordkapp Basin, and Finnmark platform, indicating a second source of sediments located in the eastnortheast. Additionally, in the Hammerfest Basin, clinoforms prograded to the southeast off the Loppa high in sequences 5-6. Low-relief (35-60 m [115-197 ft]], high-gradient, and oblique clinoforms are observed within sequence 2 in the western Bjarmeland platform. The high-gradient foresets are interpreted as potential coarse-grained deposits or as a result of clinoforms prograding to progressive deeper waters, resulting in steeper foresets. Clinoforms located in the eastern part of the study area are interpreted as sourced by a mud-rich system, reflecting a long transportation distance. However, thin, heterolithic patterns in the gamma-ray log possibly reflect thin, sheetlike sands. The height of the clinoforms seems to be a factor controlling the sediment bypass to deep water in the study area. When the height is more than 200 m (656 ft), bottomset deposits are common. This study contributes to a better understanding of the paleogeography and the evolution of the frontier southwestern Barents Sea during the Early Cretaceous and to comprehending the variables increasing the bypass of coarse-grained sediments to deep-water settings. [ABSTRACT FROM AUTHOR]

A new early Campanian rift phase related to the opening of the Labrador Sea has been recognised in the Nuussuaq Basin, West Greenland. A major angular and erosional unconformity separates deltaic deposits of the upper Albian-lowermost Campanian Atane Formation from fully marine gravity flow deposits of the lower-middle Campanian Aaffarsuaq member of the Itilli formation. Dating of this unconformity was achieved by new field work in the classic Agatdalen area and neighbouring valleys which placed known ammonite localities in an overall stratigraphic scheme and integrated the ammonite dating with a re-evaluation of old and recently collected palynological samples. On the basis of a sedimentological analysis the sediments of the Atane Formation can be classified as pre-rift with respect to Campanian rifting, and the Aaffarsuaq member can be divided into a rift-initiation and main-rift succession. The pre-rift sediments of the Atane Formation are deltaic. The uppermost preserved Atane cycle is 84m thick and is by far the thickest cycle recognised in this formation, suggesting a relative sea-level rise in late Santonian time that was possibly a result of tensional sagging preceding the rift phase. The rift-initiation phase is marked by the major, in places angular, unconformity, locally succeeded by fluvial deposits of the Itivnera beds. During the time of maximum rate of fault displacement sedimentation was outpaced by subsidence, creating relief in the basin. Sedimentation during the main-rift phase was chaotic. Deposition took place mainly from gravity flows in a channelized footwall fan system. During tectonically quiet periods heterolithic sediments were dominantly deposited from low-density turbidity currents in small shallow channels, whereas sandstones and conglomerates were deposited from high-density turbidity currents and debris flows in major channels following tectonically more active periods. Angular unconformities and major erosional surfaces are frequently present underneath the major coarse-grained turbidite channels and several syn-depositional faults are present in the succession, suggesting that these channels formed in response to continued structural movements in the early Campanian.

AbstractThe dinoflagellate cyst assemblages from four Lower Cretaceous sections from Melville Island, Axel Heiberg Island and Ellesmere Island in the Northwest Territories, Canada are described. The sections represent the upper part of the Isachsen Formation and the Christopher Formation. The strata studied comprise a composite stratigraphic section of approximately 1400m of shale and siltstone deposits. The study of 33 samples yielded 83 dinoflagellate cyst species, which date the strata as late Barremian to early late Albian. The flora discussed is correlative with assemblages described from other parts of the arctic area. This study provides new and detailed palynological information about the Lower Cretaceous of the Arctic Islands. Comments are included on the morphology and ranges of: Acanthaulaxsp. aff. A.? tenuiceras, Apteodiniumsp. cf. A. maculatumssp. grande, Balmulasp. cf. B. tripenta, Batioladinium longicornutum, Batioladinium shaftesburiense, Canningia reticulata, Catastomocystis spinosa, Circulodiniumsp. cf. C. attadalicum, Conosphaeridiumsp., Cribroperidiniumsp. aff. C. conopium, Fromea triquetra, Muderongia pariata, Nyktericysta davisii, Nyktericysta? vitrea, Nyktericystasp., Pseudoceratiumsp. aff. P. toveae, Pseudoceratiumsp., Rhombodella paucispina, Senoniasphaera microreticulata, Vesperopsis mayiand Vesperopsis nebulosa.