Geochronological constraints on Caledonian strike–slip displacement in Svalbard, with implications for the evolution of the Arctic

• Published in: Terra Nova
• Main Authors: Faehnrich, Karol, Majka, Jarosław, Schneider, David, Mazur, Stanisław, Manecki, Maciej, Ziemniak, Grzegorz, Wala, Virginia T., Strauss, Justin V.
• Other Authors: Narodowym Centrum Nauki, Akademia Górniczo-Hutnicza im. Stanislawa Staszica
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2020
• Subjects: Geology; Arctic; Greenland; Svalbard; Svalbard Archipelago; Vimsodden
• Online Access: http://dx.doi.org/10.1111/ter.12461; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fter.12461; https://onlinelibrary.wiley.com/doi/pdf/10.1111/ter.12461; https://onlinelibrary.wiley.com/doi/full-xml/10.1111/ter.12461

Abstract The timing of Svalbard's assembly in relation to the mid‐Paleozoic Caledonian collision between Baltica and Laurentia remains contentious. The Svalbard archipelago consists of three basement provinces bounded by N–S‐trending strike–slip faults whose displacement histories are poorly understood. Here, we report microstructural and mineral chemistry data integrated with 40 Ar/ 39 Ar muscovite geochronology from the sinistral Vimsodden‐Kosibapasset Shear Zone (VKSZ, southwest Svalbard) and explore its relationship to adjacent structures and regional deformation within the circum‐Arctic. Our results indicate that strike–slip displacement along the VKSZ occurred in late Silurian–Early Devonian and was contemporaneous with the beginning of the main phase of continental collision in Greenland and Scandinavia and the onset of syn‐orogenic sedimentation in Silurian–Devonian fault‐controlled basins in northern Svalbard. These new‐age constraints highlight possible links between escape tectonics in the Caledonian orogen and mid‐Paleozoic terrane transfer across the northern margin of Laurentia.