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Kilen is a semi-nunatak in the Flade Isblink icecap in eastern North Greenland with exposures of Mesozoic sedimentary rocks, which are part of the Wandel Sea Basin. Cretaceous marine mudstones and interbedded sandstones of the Galadriel Fjeld and Sølverbæk formations are thrusted and folded in large open folds at Gåseslette in the southeastern part of Kilen. Steeply dipping strata, reflecting parasitic folds and small-scale thrusts, are exposed in low cliffs along a c. 9 km NNW–SSE stretch of the Sølverbæk river. The present study is a case study of the thermal history of these outcrops, called the Sølverbæk section. The burial temperatures are calculated from vitrinite reflectance (R o ) values. T max -measurements from Rock-Eval type pyrolysis correlate with the R o -values. The latter reflects the large-scale folds with higher temperatures in anticlines and lower in synclines. The sedimentary successions are dated on basis of dinoflagellate cysts, inoceramid bivalves and ammonites. The dataset demonstrate a correlation between the T max -measurements, maximum burial temperatures, and the preservation of dinoflagellate cysts. The burial temperature at the boundary between the Kangoq Ryg Member and the Sølverbæk Formation varies laterally through a restored section and suggest that the northern part of the section was c. 30° hotter than the southern part prior to folding. Five events are distinguished in the thermal history of the Sølverbæk section: (1) Deposition, (2) rotation of the succession, (3) thermal imprinting, (4) uplift, folding and thrusting, (5) final uplift and erosion up to present day. Following a recent structural model for Kilen events 1–3 are interpreted to be caused by Late Cretaceous rifting where (3) represents maximum burial during rifting. Event 4 is explained by basin inversion of presumed Paleocene–Eocene age. [ABSTRACT FROM AUTHOR]

The Ikorfat Fault zone in northern Nuussuaq, Central West Greenland, has preserved a hitherto unknown succession of Upper Cretaceous marine mudstones referred to the Itilli Formation, which have been removed by erosion on the footwall block and buried deeply below sea-level on the hanging-wall block. Outcrops in the fault zone provide new data on sedimentology, palynology, stable carbon isotopes and organic geochemistry in the lower part of the Itilli Formation. A new, detailed geological map of the study area is based on digital photogrammetry. Marine organic walled dinoflagellate cysts (dinocysts) demonstrate a late Cenomanian–Turonian age, coeval with the Oceanic Anoxic Event 2 (OAE2) and link the Nuussuaq Basin with the Baffin Bay and Sverdrup Basins. The Ikorfat Fault zone is part of the eastern boundary fault of the Nuussuaq Basin. Lower Campanian listric faults truncate the footwall block. Subsidence along steep normal faults continued during deposition of the volcanic Vaigat Formation of Danian to Selandian age. The downthrow of the hanging-wall block was around 2.5 km. [ABSTRACT FROM AUTHOR]

Eleven cored boreholes, with depths up to c. 360 m were drilled in north-east Baffin Bay, a frontier area offshore West Greenland by the vessel Joides Resolution. The cores were part of the Baffin Bay scientific shallow coring program, expedition 344S in 2012, funded by a consortium of eight petroleum companies. The main drilling target was a succession of dipping strata in the Kap York Basin that proved to be of Cretaceous age. Here we report the results of comprehensive core analyses involving lithofacies interpretation, palynological dating, palynofacies studies, isotope geochronology, organic geochemistry and reservoir characterization. The Lower Cretaceous succession comprises sandstones, mudstones and few thin coal beds of Albian age. Terrestrial material and a sparse and low diversity assemblage of brackish-water dinoflagellate cysts (dinocyst) species dominate the organic particles. The sedimentary environments range from floodplain to deep bay and suggest deposition in a large non-marine to brackish embayment. The kerogen type is immature to marginally mature, type III/IV, with very restricted potential for generation of petroleum or gaseous petroleum. The Upper Cretaceous sedimentary succession of Cenomanian–Turonian age consists of black marine mudstone with varying amounts of discrete sand layers. The amorphous organic material and marine dinocysts suggest that most of the succession was deposited in an anoxic–dysoxic to oxygen restricted palaeoenvironment, probably ranging from outer shelf and prodelta fringe to lower delta front. The organic richness and petroleum potential are variable. The black mudstones include organic rich intervals with TOC of 3–6%, HI of 200–350 and SPI value of 3.0, comparable to well-known petroleum source rock successions of this age worldwide. The δ13C org curves for the Cenomanian–Turonian sections display values and trends characteristic of Oceanic Anoxic Event 2 (OAE2). A marine transgression between the Lower and Upper Cretaceous successions caused dramatic changes in depositional environments. • Eleven shallow cores from Baffin Bay, Greenland dated Albian–Turonian (Cretaceous). • Studies of lithofacies, palynology, palynofacies, isotopes, geochemistry, porosity. • Net sandstone thickness of 100 m with an average porosity of 25%. • TOC 3–6%, HI 200–350, SPI 3.0 values of organic-rich intervals indicate source rock. • δ13C org curves for the Cenomanian–Turonian corresponds to the Oceanic Anoxic Event 2. [ABSTRACT FROM AUTHOR]

A new Palaeogene dinoflagellate cyst stratigraphy from offshore West Greenland has been described based on the strata from the Hellefisk-1, Ikermiut-1, Kangaˆmiut-1, Nukik-1, Nukik-2 and Qulleq-1 wells. Twenty-one palynological intervals are defined from the Late Eocene to the late Early Paleocene. This stratigraphy has been correlated with a new microfossil zonation and previous established North Sea zonations. The stratigraphy and well correlation are based on last appearance datum events and abundances of stratigraphically important species from 355 samples, 148 of which are sidewall core samples. A major middle Eocene hiatus spanning the early Lutetian and a major Early Paleocene hiatus spanning the Late Santonian, Late Cretaceous to the early Danian have been recognised from the offshore deposits. [Copyright &y& Elsevier]

The microfossil and palynofloral assemblages of the Paleocene to middle Eocene succession, offshore West Greenland, have been investigated. Several taxa, which are believed to reflect specific palaeoenvironments were selected, and their relative abundances measured. Subsequently, an interpretation of the changing depositional settings in the Hellefisk-1, Ikermiut-1, Kangaˆmiut-1, Nukik-1 and Nukik-2 boreholes through the lower Palaeogene has been made. [Copyright &y& Elsevier]

Sedimentological models for rift shoulders have poorly documented the effect of adjacent fault systems on drainage patterns. In this study we investigate the Loppa High, an ancient tilted rift shoulder located in the southwestern Barents Sea. We use seismic and well data, sedimentological log descriptions, and biostratigraphic information to understand the drainage patterns and the Early Cretaceous geological history of the Loppa High. This study provides an example of how the drainage systems in low-gradient flanks of a rift shoulder can be modified and confined by normal faults occurring almost orthogonal to the main fault system. These orthogonal faults might have acted as preferential sediment routes. Thus, potential deposits of the main drainage systems directed to the low gradient flank are found almost exclusively associated with grabens formed due to these orthogonal faults. The Early Cretaceous evolution of the Loppa High is summarized as follow: 1) during the Boreal Berriasian/Volgian to early Barremian, the Asterias and the Bjørnøyrenna fault complexes were active. Diachronous shallow to eventually deep-marine fans and incised valleys were developed along the southern and western flanks of the Loppa High; 2) late Barremian–Aptian fault activity is interpreted along the Ringvassøy Loppa Fault Complex. A second generation of incised valleys and their related shallow-marine fans were formed in the western flank of the Loppa High; and 3) during late Aptian–early Albian the Loppa High and the Hammerfest Basin were tilted eastwards. The latter event triggered a switch in depocenter location and development of shelf-margin clinoforms downlapping in close proximity to the eastern flank of the high. [ABSTRACT FROM AUTHOR]

New interpretations are reported of the sedimentology and sequence stratigraphy of the Palaeogene sediments encountered by the boreholes Hellefisk-1, Ikermiut-1, Kangaˆmiut-1, Nukik-1 and Nukik-2 offshore southern West Greenland. These interpretations, together with new biostratigraphic and palaeoenvironmental interpretations, have been used to correlate the boreholes and to calibrate seismic sequences interpreted on a grid of reflection seismic data. The interpreted seismic sequences lie between major regional unconformities of Danian and mid-Eocene age.The new interpretations show that the area offshore southern West Greenland was subject to major uplift and erosion during the Danian when latest Cretaceous sediments were removed. Sedimentation restarted in the late Danian, coevally with major volcanism in central West Greenland and the start of sea-floor spreading in the Labrador Sea. Late Paleocene sediments were deposited in a predominantly extensional tectonic environment. The extensional stresses continued in most areas during the early Eocene, but in the northern and northwestern part of the basins, a transtensional system developed along the strike-slip faults that transferred sea-floor spreading movements between the Labrador Sea and Baffin Bay.Sediment input to the basins was predominantly from the north, possibly from a major river system flowing out of central Greenland. Lesser amounts of sediment came from the east, from the mainland of Greenland, and minor amounts from the west. The thickness of total sediment decreases substantially from north to south. The sediments were deposited in environments that ranged from fresh-water/marginal marine to upper bathyal. Proximal environments are probably generally sand-prone, but distal environments probably contain larger amounts of mud, some of which could contain a mature source rock for oil. Basin-floor fans, syn-tectonic wedges and turbidite channel complexes that could act as hydrocarbon reservoirs sealed by surrounding muds have been identified in many of the seismic sequences. [Copyright &y& Elsevier]

The Cenomanian–Turonian transition includes the youngest of the two so-called Cretaceous Oceanic Anoxic Events, sometimes also referred to as the "Bonarelli Event". This is an interval of global deposition of organic-rich oceanic deposits, including some of the most prolific petroleum source rocks of the World. However, in the greater North Atlantic realm, little direct evidence of notable volumes of rich Cenomanian–Turonian petroleum source rocks exists. As part of a major study of the Cretaceous succession in northeast Greenland between 2009 and 2012, a fully cored borehole (Nanok-1) on eastern Hold with Hope was drilled to penetrate a poorly or non-exposed stratigraphic succession including the Cenomanian–Turonian transition. The Nanok-1 penetrated 160.5 m of Cenomanian to Campanian clastic deposits and terminated at a TD of 168.35 m in an igneous intrusion. Although none of the deposits penetrated qualify as a petroleum source rock, a downwards increasing trend in petroleum source potential starting at c. 100m hint at the existence of such rocks at levels deeper than the TD of the well. The downwards increasing trend in petroleum generation potential is curtailed by maturation from c. 140m, but assuming the trend would have prevailed, were it not for the intrusion, the presence of at least a marginal source rock would be expected at the level of the sill and deeper. The presumed existence of petroleum source rocks below the TD of the borehole is supported by the presence of marked oil staining in sandstones (i.e. migrated petroleum) at shallower levels of the drilled succession. The hopane and sterane distributions and stable carbon isotopic compositions and age-specific nordiacholestane ratios of the oil stains are compatible with an origin from the Cretaceous succession, while the Jurassic can be ruled out. The oil stains recorded were probably generated from a marine shale source rock of Cretaceous age, containing a significant proportion of terrigenous organic matter. The possible presence of at least one marginal petroleum source rock in the mid-Cretaceous succession at the Nanok-1 location has implications for the exploration potential of the conjugate margin. Hence, comparison of sediment accumulation histories of the Møre and Vøring basins and northeast Greenland suggests that the presumed source rock was deposited before the accommodation space at the Nanok-1 location was exhausted. Thus, coeval sediment starvation and deposition of more condensed and richer petroleum source rocks may have prevailed in the offshore basins to the east during the mid-late Cenomanian. This potential source rock will thus be slightly older than Cenomanian–Turonian source rocks that are important worldwide. • The Nanok-1 fully cored borehole, Hold with Hope, NE Greenland, penetrated c.160m of Cenomanian–Campanian deposits and terminated in an intrusion. • The borehole did not encounter any petroleum source rocks, but prominent oil stains were found in sandstones drilled by the well.. • The oil stains were generated from a Cretaceous-age marine shale source rock. • The oil stains document the existence of a Cretaceous-age source rock with capacity for generation of liquid petroleum. • The results are important for the ongoing discussion of potential Cretaceous petroleum source rocks in the North Atlantic region. [ABSTRACT FROM AUTHOR]