The timing of the Svalbardian Orogeny in Svalbard: a review

Abstract. In the Late Devonian to earliest Mississippian, Svalbard was affected by a short-lived episode of deformation named Svalbardian Orogeny. This event resulted in intense folding and thrusting sedimentary successions. Deformation stopped prior deposition Carboniferous Permian strata Billefjorden Gipsdalen groups, which lie unconformably over folded strata. Later on, presumed structures were reworked during Eurekan tectonism early Cenozoic partly eroded. At present, records are only preserved narrow N–S-trending belts central, northern, western, southern Spitsbergen. Despite extensive field studies, timing Orogeny is poorly constrained remains matter debate places because conflicting ages complex tectonic history Svalbard. The present contribution aims at reviewing discussing all available age constraints for tectonism, including notably palynological, paleontological, geochronological evidence. has great implications plate reconstructions Arctic regions Palynological paleontological evidence suggest that Mimerdalen Subgroup upper Givetian lower Frasnian (ca. 385–380 Ma) Group mid-Famennian Upper Mississippian 365–325 age, constraining central northern Spitsbergen 383–365 Ma if it ever occurred. indicate Adriabukta Formation Middle therefore cannot have been involved event, thus suggesting strain-partitioning processes had major role localizing weaker stratigraphic units. few yielding Devonian–Mississippian may reflect either contraction or extensional no use validate invalidate occurrence event. On contrary, contradicting lines used support new regional geophysical studies subjected continuous extension from late Silurian times.