A multi-disciplinary investigation of the AFEN Slide: the relationship between contourites and submarine landslides

Gatter, R., Clare, M. A., Hunt, J. E., Watts, M. , Madhusudhan, M. B. N., Talling, P. J. and Huhn, K. (2020) A multi-disciplinary investigation of the AFEN Slide: the relationship between contourites and submarine landslides. Geological Society Special Publications, 500, pp. 173-193. (doi: 10.1144/sp500-2019-184)

Abstract

Contourite drifts are sediment deposits formed by ocean bottom currents on continental slopes worldwide. Although it has become increasingly apparent that contourites are often prone to slope failure, the physical controls on slope instability remain unclear. This study presents high-resolution sedimentological, geochemical and geotechnical analyses of sediments to better understand the physical controls on slope failure that occurred within a sheeted contourite drift within the Faroe–Shetland Channel. We aim to identify and characterize the failure plane of the late Quaternary landslide (the AFEN Slide), and explain its location within the sheeted drift stratigraphy. The analyses reveal abrupt lithological contrasts characterized by distinct changes in physical, geochemical and geotechnical properties. Our findings indicate that the AFEN Slide likely initiated along a distinct lithological interface, between overlying sandy contouritic sediments and softer underlying mud-rich sediments. These lithological contrasts are interpreted to relate to climatically controlled variations in sediment input and bottom current intensity. Similar lithological contrasts are likely to be common within contourite drifts at many other oceanic gateways worldwide; hence our findings are likely to apply more widely. As we demonstrate here, recognition of such contrasts requires multi-disciplinary data over the depth range of stratigraphy that is potentially prone to slope failure.

• Item Type: Articles
• Additional Information: This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 721403. We acknowledge research funding from the UK National Environmental Research Council(NE/K0008X/1) for sediment core collection. M. Clare was supported by the Climate Linked Atlantic Sector Science (CLASS) programme (Natural Environment Research Council Grant No. NE/R015953/1).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Bompard, Dr Millie
• Authors: Gatter, R., Clare, M. A., Hunt, J. E., Watts, M., Madhusudhan, M. B. N., Talling, P. J., and Huhn, K.
• College/School: College of Science and Engineering > Scottish Universities Environmental Research Centre
• Journal Name: Geological Society Special Publications
• Publisher: The Geological Society
• ISSN: 0305-8719
• ISSN (Online): 2041-4927
• Published Online: 28 April 2020
• Copyright Holders: Copyright © 2020 The Authors
• First Published: First published in Geological Society Special Publications 500:173-193
• Publisher Policy: Reproduced under a Creative Commons license