Ammassalik Composite Tectono-Sedimentary Element, southern East and SE Greenland Rifted Margin, Denmark Strait

Abstract

Abstract The Ammassalik Composite Tectonic-Sedimentary Element (CTSE) comprises the Ammassalik and the Kangerlussuaq rift basins located on the southern East and SE Greenland margin. The offshore Ammassalik Basin is one of the last virtually undescribed segments of the NE Atlantic continental margins with a very sparse seismic coverage. The basin is compartmentalized into smaller sub-basins up to at least 4 km deep blanketed by Paleocene–Eocene basalt towards the east. Albian sediments cored in the basin suggest, at least partly, a Cretaceous age, making the Ammassalik Basin a likely analogue to basins on the conjugate outer British continental margin. However, the deeper, undated succession could include pre-Cretaceous strata. Located onshore southern East Greenland, the Kangerlussuaq Basin contains a Barremian/Aptian–Danian succession of estuarine–marine strata overlain by Paleocene fluvial sediments, basalts and thinner marine interludes. The sedimentary succession is less than 1 km thick. Cenozoic uplift and erosion affected both basins. Unlike the Kangerlussuaq Basin, the Ammassalik Basin may contain a working petroleum system. Together with the very large fault structures identified in the basin, this makes the Ammassalik Basin an interesting future exploration target with the main challenge being to demonstrate a mature source rock, together with qualifying the effects of Paleocene–Eocene magmatism and Cenozoic exhumation on the potential petroleum system.