Abstract

The North Slope of Alaska has yielded several high-profile discoveries within underexplored Cretaceous systems during the last three years. Despite this success (the combined oil in place of the three largest discoveries is estimated at 3.95 BBL), exploration risk for this particular interval remains poorly defined. Exploration across Arctic Alaska is also limited by the remoteness of the region, and this is compounded by a lack of infrastructure, which is likely to slow development of assets. Yet, with the gradual relaxation of legislation and the return to higher oil prices, interest in this super basin is likely to grow over the next decade. Understanding the geological controls acting upon key prospective intervals is therefore crucial in order to reduce risk and inform future investment decisions.

In this webinar, we will assess the spatial distribution of play elements associated with the North Slope’s shallow-marine deltaic Nanushuk and deepsea-fan Torok formations. To tackle our objectives, we employ a global plate tectonic framework, along with sequence stratigraphic interpretation, to characterize the evolution of the basin and the stratigraphic architectures therein. Used in conjunction with geochemical and petrophysical datasets, these tools provide a powerful basis for predicting and constraining the age and depositional extent of key source and reservoir units central to the emerging Cretaceous Nanushuk and Torok plays.

We will show how maximum burial most likely exerts the greatest control on reservoir quality, with widespread loss of porosity observed with depth. Spatially, both plays were buried near the northeast end of the North Slope basin. Coupled with the prediction of thicker reservoir facies outlined in this study, the eastern part of the basin appears more prospective.