Late Cenozoic uplift and volcanism on Spitsbergen: Caused by mantle convection?

Abstract

Regional tectonic uplift, heat-flow measurements, and P-T estimates on upper-mantle xenoliths associated with Neogene volcanic rocks indicate a strongly thinned (∼50 km thick) lithosphere beneath Svalbard, 650 km north of Scandinavia. Data on Neogene volcanic rocks and xenoliths indicate an ∼50 °C temperature anomaly in the underlying asthenosphere, together with volatile-rich conditions in the upper mantle. The Svalbard uplift is one of several Cenozoic epeirogenic uplifts along the margins of the North Atlantic. Boundary processes occurring where hot-spot-influenced asthenosphere abuts cold, deep continental lithosphere seem to be likely explanations for the uplifts.