Shard concentrations and geochemical composition of tephra layers from deep sediment cores MD99-2284, GS16-204-22CC and GS16-204-18CC. Tephra horizons identified in the western North Atlantic and Nordic Seas during the Last Glacial Period ...

• Main Authors: Rutledal, Sunniva, Berben, Sarah M P, Dokken, Trond, van der Bilt, Willem G M, Cederstrøm, Jan Magne, Jansen, Eystein
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 2020
• Subjects: Nordic Seas; North Atlantic
• Online Access: https://dx.doi.org/10.1594/pangaea.913678; https://doi.pangaea.de/10.1594/PANGAEA.913678

Geochemically distinct volcanic ash (tephra) deposits are increasingly acknowledged as a key geochronological tool to synchronize independent paleoclimate archives. Recent advances in the detection of invisible (crypto) tephra have led to the ongoing establishment, development and integration of regional tephra lattices. These frameworks offer an overview of the spatial extent of geochemically characterized tephra from dated eruptions – a valuable tool for precise correlation of paleorecords within these areas. Here, we harness cryptotephra analysis to investigate the occurrence of two well-known tephra markers from the Last Glacial Period (i.e. FMAZ II-1 (26.7 ka b2k) and NAAZ II (II-RHY-1) (55.3 ka b2k)), in marine sediment cores from the Nordic, Irminger and Labrador Seas. In addition, we assess the imprint of bioturbation on two of these tephra deposits using Computed Tomography (CT) imagery. We have successfully identified FMAZ II-1 in the Nordic and Irminger Seas. The tephra deposit is a visible ...