Reconstructing Palaeozoic and Mesozoic tectonic evolution of Novaya Zemlya: combing geochronology and thermochronology

To better understand the sediment provenance and exhumation history of Novaya Zemlya's Mesozoic fold–thrust belt, we apply detrital zircon U-Pb geochronology combined with zircon and apatite fission track analyses to samples from the Precambrian to late Permian siliciclastic successions of the southern and northern islands. The Silurian to early Devonian samples are dominated by zircons (1.14–0.9 Ga) characteristic of the Sveconorwegian Orogen. Zircon fission track ages for individual units are older than their stratigraphic ages and consistent with single-age population distributions. The zircon fission track results document no annealing after deposition and therefore preserve provenance information, which indicates that the source rock(s) of each sample most likely experienced the same thermal event. The results support the erosion and recycling of Sveconorwegian-aged zircon from the Fennoscandian shield during Caledonian orogenesis to the Barents Sea Shelf and Novaya Zemlya. Apatite fission track ages and thermal modelling identify a rapid cooling event at 220–210 Ma, consistent with late Triassic deformation on Novaya Zemlya.