Northern Svalbard Composite Tectono-Sedimentary Element

Abstract

The Northern Svalbard Composite Tectono-Sedimentary Element (CTSE) comprises Proterozoic, Early Paleozoic, and Devonian sedimentary rocks preserved in northern Svalbard and on the adjacent shelf margin. Here, the sedimentary strata of the CTSE are preserved between complexes of metamorphic and crystalline basement rocks. The Northern Svalbard CTSE covers four main tectonostratigraphic elements: Tonian syn-rift, Neoproterozoic to Cambrian post-rift, Ordovician passive margin, and late Silurian?/Devonian syn-extensional basins. The oldest documented sedimentary strata are greywacke and shale deposited after the Greenvillian Orogeny and assumed to be younger than 980-960 Ma. The present CTSE further includes Cambrian-Ordovician sedimentary rocks in Ny-Friesland and Nordaustlandet, while the dominant part of the CTSE are continental Old Red Sandstone sediments of the late Silurian?/Early Devonian Red Bay and Siktefjellet groups and the Early-Late Devonian Andreé Land Group onshore northern Spitsbergen. Locally, the Cambrian-Ordovician formations contain petroleum source rocks with moderate total organic carbon contents and relatively high hydrogen index values, suggesting a good potential for oil generation. There are possible reservoirs, seals, and traps in some of the basins, but the CTSE generally holds a very limited potential as a petroleum province, particularly as the region is under strict environmental protection