Detailed survey of the western end of the Hurd Deep (English Channel): new facts for a tectonic origin
Lericolais, G.; Guennoc, P.; Auffret, J.-P.; Bourillet, J.-F.; Berne, S. (1996). Detailed survey of the western end of the Hurd Deep (English Channel): new facts for a tectonic origin, in: De Batist, M. et al. (Ed.) Geology of siliciclastic shelf seas. pp. 203-215 In: De Batist, M.; Jacobs, P. (Ed.) (1996). Geology of siliciclastic shelf seas. Geological Society Special Publication, 117. The Geological Society (London): London. ISBN 1-897799-67-5. 345 pp., more In: Hartley, A.J. et al. (Ed.) Geological Society Special Publication. Geological Society of London: Oxford; London; Edinburgh; Boston, Mass.; Carlton, Vic.. ISSN 0305-8719; e-ISSN 2041-4927, more |
| Authors | | Top | - Lericolais, G.
- Guennoc, P.
- Auffret, J.-P.
| - Bourillet, J.-F.
- Berne, S.
| |
| Abstract | During the 'Sédimanche 2' survey, a study of the western end of the Hurd Deep was carried out using new high-resolution geophysical techniques. The obtained results, i.e. bathymetry, acoustical imaging and seismic profiling, determine a tectonic control on the first excavation of Hurd Deep, a complex infilling and present-day sediment dynamics. In size and geometry , the Hurd Deep is a unique feature in the English Channel, terminating abruptly at its western end. It is incised into Jurassic and Late Cretaceous sediments. Except for the trough itself, the sea floor is extensively levelled at a depth between 70 and 90m. The Hurd Deep infill, revealed by high-resolution seismic data, is characterized by a set of five main sequences. The thickness of the infill averages 80 m along the axis of the trough and reaches a maximum of 140m. The side-scan sonar mosaic shows active sediment dynamics characterized by the presence of dunes on the southern part of the present trough. A Neogene tectonic origin for the Hurd Deep and the interplay of erosion and sedimentation during the last glacial and interglacial periods are presented in terms of geomorphology and sequence stratigraphy. |
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