Cyclic sedimentation on the Faeroe Drift 53-10 ka BP related to climatic variations

• Published in: Geological Society, London, Special Publications
• Main Authors: Rasmussen, Tine L., Thomsen, Erik, Van Weering, Tjeerd C. E.
• Format: Book Part
• Language: English
• Published: Geological Society 1998
• Subjects: Gateway The; Greenland; Norwegian Sea; Greenland ice cores; Iceland; North Atlantic
• Online Access: https://oceanrep.geomar.de/id/eprint/39504/; https://oceanrep.geomar.de/id/eprint/39504/1/Rasmussen.pdf; https://doi.org/10.1144/GSL.SP.1998.129.01.16

More than 15 sedimentary cycles dated to the last glacial period (53-10 ka BP) have been recognized in a contourite deposit on the Faeroe Drift in the southern part of the Norwegian Sea. Each cycle consists of a silty, basaltic lower part and a clayey, acidic (siliceous) upper part. The sedimentary cycles can be accurately correlated with the Dansgaard-Oeschger temperature cycles in the Greenland ice cores, and it appears that the cyclic sedimentation was controlled by climatic and palaeoceanographic changes. The basaltic layers were deposited during warm interstadial periods in a current regime that resembles the modern circulation system in the North Atlantic region. Deep bottom-water created by thermohaline convection in the Norwegian-Greenland Seas flowed along the Iceland-Faeroe Ridge into the Atlantic Ocean, with the Faeroe-Shetland Channel as the main gateway. The source of the basaltic sediments was the volcanic rocks and detritus on the Iceland-Faeroe Ridge and on the shelf of eastern Iceland. The fine-grained acidic (siliceous) layers were deposited during intervening cold periods, in which convection took place in the subpolar North Atlantic Ocean and the circulation was reversed in the Faeroe-Shetland Channel. The acidic deposits were carried into the Norwegian Sea from the Hebrides and West Shetland shelves and the northeastern Atlantic Ocean.