The continental Triassic succession north of 72° in East Greenland has seen little investigation but is key in understanding how facies belts vary towards the East Greenland Shelf, and more widely in the North Atlantic region, through this period. This study presents sedimentological analysis of exposures in northern Traill Ø (the Mols Bjerge) and further north in northern Geographical Society Ø (Laplace Bjerg). These sections are correlated with the more widely studied succession which lies to the south, in Jameson Land and broad scale palaeogeographical reconstructions of the North Atlantic are presented. A largely continental Triassic succession of 1445 m was recorded from the Mols Bjerge. However, a 125 m thick clean sand unit (the Vega Sund Member), which includes in its upper part the Gråklint Beds, is re‐interpreted as of shallow marine origin. Over 1200 m of Triassic strata were recognized on Laplace Bjerg. Within this succession 300 m of clean, cross‐bedded sandstones are recorded and are correlated with the Vega Sund Member recorded in the Mols Bjerge. The northward increase in thickness of marine strata developed at this time provides evidence for a more extensive marine influence in the north. This work has important implications for regional palaeogeographies and the character of the Triassic succession in adjacent basins, in particular, constraining the southern extent of the Boreal Ocean during the Mid to Late Triassic. Furthermore, the correlations made places bitumen staining, reported from Laplace Bjerg, within Triassic strata, suggesting the viability of a Triassic play at depth in adjacent offshore basins.

Exhumed hydrocarbon traps are globally rare but can offer important insight to subsurface systems, not available through the collection of standard industry data sets. Core, wireline and seismic data leave significant scale gaps which only high quality mega-scale outcrops can fill. East Greenland contains world class examples of exhumed hydrocarbon traps, in both scale and the quality of exposure. Difficulty in accessing this remote region has left these features relatively understudied. This study first examines the age of the strata involved within the exhumed traps. Biostratigraphic and provenance analysis were carried out so as both the local and regional context of the hydrocarbon staining could be understood. This is of particular importance for future exploration strategies in the North Atlantic region. The second aim of this

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During the Early Triassic the Jameson Land Basin (Central East Greenland) was located around 30°N, in the Northern arid belt, but by the Early Jurassic was positioned at a latitude of approximately 50°N. This study examines the record of this transition through a largely continental succession using clay mineralogy, sedimentology, petrography and heavy mineralogy. The Jameson Land Basin is aligned north-south and is 280 km long and 80 km wide. Following an Early Triassic marine phase the basin was filled by predominantly continental sediments. The Early-to-Late Triassic succession comprises coarse alluvial clastics (Pingo Dal Formation) overlain by a succession of finegrained evaporite-rich playa/lacustrine sediments (Gipsdalen Formation), indicative of arid climatic conditions. The overlying buff, dolomitic and then red lacustrine mudstones with subordinate sandstones (Fleming Fjord Formation) record reduced aridity. The uppermost Triassic grades into dark organic-rich, and in places coaly, mudstones and buff coarse-grained sandstones of lacustrine origin that belong to the Kap Stewart Group, which spans the Triassic-Jurassic boundary, and appear to record more humid climatic conditions. Clay mineralogy analyses highlight significant variations in the kaolinite/illite ratio, from both mudstone and sandstone samples, through the Triassic and into the earliest Jurassic. Complementary heavy mineral analyses demonstrate that the variations recognised in clay mineralogy and sandstone maturity through the Triassic-Early Jurassic succession are not a product of major provenance change or the effect of significant diagenetic alteration. The observed variations are consistent with sedimentological evidence for a long-term trend towards more humid conditions through the Late Triassic to Early Jurassic, and the suggestion of a significant pluvial episode in the mid-Carnian.

Heavy mineral provenance data presented in this article reinforce evidence for significant late Palaeogene deformation and relief formation along the western margin of the Central Andean Plateau. Late Eocene–Oligocene onset of molasse-type sedimentation records initial range uplift. Strikingly different basement sources of sediments deposited to the east and west of the Late Palaeogene range indicate that initial relief development was governed by a bivergent thrust system. Significantly higher sediment accumulation rates to the east of the range compared to the west suggest that the generated relief acted already as an effective orographic barrier at that time. Higher precipitation and denudation along the eastern slope facilitated deeper erosion of the trust bel

In this study, single-grain mineral geochemistry, detrital zircon geochronology, and conventional heavy-mineral analysis are used to elucidate sediment transport pathways that existed in the North Atlantic region during the Triassic. The presence of lateral and axial drainage systems is identified and their source regions are constrained. Axial systems are suggested to have likely delivered sediment sourced in East Greenland (Milne Land–Renland) as far south as the south Viking Graben (>800 km). Furthermore, the data highlight the existence of lateral systems issuing from Western Norway and the Shetland Platform as well as a major east-west–aligned drainage divide positioned adjacent to the Milne Land– Renland region. This divide separated the catchments that flowed north to the Boreal Ocean from those that flowed south into a series of endoreic basins and, ultimately, the Tethys Sea. A further potential drainage divide is identified to the west of Shetland. The data presented and the conclusions reached have major implications for reservoir prediction, as well as correlation, throughout the region. Furthermore, understanding the drainage networks that existed during the Triassic can help constrain paleogeographic reconstructions and provides an important framework for the construction of facies models in the region.

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