East Greenland as an analogue and source to the Jurassic and Cretaceous petroleum systems of Mid-Norway

East Greenland offers superb exposures of several kilometers of post-Caledonian sedimentary units. These have accumulated during Devonian wrenching, Carboniferous tectonic quiescence, Mid Permian compression, and protracted rifting from the Late Permian. Rifting culminated with widespread volcanism and separation of the Jan Mayen microcontinent from East Greenland in the Paleogene. CASP has conducted annual fieldwork in East Greenland for the last three decades. Most of this work focused on the Jurassic and Cretaceous succession, which are of greatest interest in terms of hydrocarbon exploration offshore.

The Jurassic and Cretaceous stratigraphy exposed in East Greenland is analogous to the offshore succession in Mid-Norway and the NE Greenland Shelf. This time interval is proven to be rich in excellent quality reservoirs and source rocks on the Halten Terrace. In addition, excellent reservoirs are found within the Early to Middle Jurassic of the Barents Shelf. Multi- proxy provenance work on outcrop and well samples (heavy mineral criteria such as RuZi, heavy mineral chemistry, and detrital zircon age data) has established East Greenland as a likely source of much of the sediment that comprises Jurassic and Cretaceous reservoirs in Mid-Norway. In this context, there is significant motivation to better understand the depositional environment and distribution of Jurassic and Cretaceous units in East Greenland.

Previous regional chronostratigraphic schemes have provided the basis for illustrating the stratigraphic variability recognized across East Greenland. However, these do not provide a clear picture of regional variations in unit thicknesses.

In order to rectify a lack of thickness information for Jurassic and Cretaceous units, thickness-based composite sections have been compiled from throughout East Greenland, leading to the production of a regional thickness-based correlation panel. In addition, various data pertaining to source and reservoir potential have been compiled along with the composite sections. This includes petrography, heavy mineral analysis, heavy mineral chemistry, detrital zircon U-Pb ages, poroperm, and TOC/Rock Eval Pyrolysis data.

Marked thickness variations of sedimentary units highlight rifting phases in the Bajocian and Oxfordian to Volgian. Crustal structure probably played an important role, with increased rifting in the Mid Volgian evident only to the north of Scoresby Land where mudstones were deposited on the crests of tilted fault blocks with concomitant conglomerate deposition in hanging wall successions. In contrast, in southern Jameson Land Early to Mid Volgian deep marine strata are overlain by shallow marine Vogian, Ryazanian and Valanginian strata. The amount of extension reduced from the Hauterivian to the Mid Albian and there is little evidence for rifting in East Greenland from the Mid Albian onwards.

Variations in formation thicknesses and source and reservoir properties have been established in East Greenland. This has revealed the net:gross of the Jurassic and Cretaceous and therefore a better understanding of the regional distribution of source and reservoir units. Gaps in the data can now be readily identified and addressed if required. This work also sheds new light on the rift history during the Jurassic and Cretaceous between Greenland and Norway.