Skip to main content Accessibility help
×
Home

The seabed geomorphology and geological structure of the Firth of Lorn, western Scotland, UK, as revealed by multibeam echo-sounder survey

  • John A. Howe (a1), Roger Anderton (a2), Riccardo Arosio (a1), Dayton Dove (a3), Tom Bradwell (a3), Philip Crump (a1), Rhys Cooper (a3) and Andre Cocuccio (a4)...

Abstract

This paper presents recently collected swath bathymetry from the Firth of Lorn. 553 km2 of data were collected during 2012–2013 as part of the INIS Hydro (Ireland, Northern Ireland and Scotland Hydrographic Survey) programme.

The area proves to consist of bedrock-dominated seabed, divided into narrow, stratigraphically-constrained and glacially-over-deepened basins. The bedrock is composed of late Proterozoic Dalradian metasediments overlain unconformably by Old Red Sandstone (ORS) sediments and lavas of ?Silurian-age. The central region of the Firth of Lorn is dominated by a vertical cliff, up to 150 m high and extending for approximately 24 km. This feature, here termed the Insh Fault, may have originated as a Dalradian extensional fault, been reactivated as an ORS feature and now forms a fault-line scarp with resistant ORS rocks on the downthrown side, flanking the more deeply eroded metasediments exposed in the basin. Tertiary intrusives are common, in particular, swarms of Paleocene dolerite dykes exposed on the sediment-free bedrock surfaces, and can be traced for many kilometres.

Evidence for past glaciation is widespread, manifest in the extensive erosion of the bedrock platforms and the abundance of well-preserved moraines and over-deepened basins. The survey region includes the Corryvreckan Whirlpool and Great Race, beneath the tidal flows of which occur submarine dunes.

    • Send article to Kindle

      To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about sending to your Kindle.

      Note you can select to send to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

      Find out more about the Kindle Personal Document Service.

      The seabed geomorphology and geological structure of the Firth of Lorn, western Scotland, UK, as revealed by multibeam echo-sounder survey
      Available formats
      ×

      Send article to Dropbox

      To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Dropbox.

      The seabed geomorphology and geological structure of the Firth of Lorn, western Scotland, UK, as revealed by multibeam echo-sounder survey
      Available formats
      ×

      Send article to Google Drive

      To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Google Drive.

      The seabed geomorphology and geological structure of the Firth of Lorn, western Scotland, UK, as revealed by multibeam echo-sounder survey
      Available formats
      ×

Copyright

References

Hide All
Anderton, R. 1985. Sedimentation and tectonics in the Scottish Dalradian. Scottish Journal of Geology 21(4), 407–36.
Anderton, R. 1988. Dalradian slides and basin development: a radical interpretation of stratigraphy and structure in the SW and Central Highlands of Scotland. Journal of the Geological Society, London 145, 669–78.
Arnaud, E. & Fairchild, I. J. 2011. The Port Askaig Formation, Dalradian Supergroup, Scotland. In Arnaud, E., Halverson, G. P. & Shields-Zhou, G. (eds) The Geological Record of Neoproterozoic glaciations. Geological Society, London, Memoir 36, 635–42.
Bradwell, T., Fabel, D., Stoker, M., Mathers, H., McHargue, L. & Howe, J., 2008, Ice caps existed throughout the Late glacial interstadial in northern Scotland, Journal of Quaternary Science 23, 401–07.
Barber, P. L., Dobson, M. R. & Whittington, R. J. 1979. The geology of the Firth of Lorne, as determined by seismic and dive sampling methods. Scottish Journal of Geology 15, 217–30.
Binns, P. E., McQuillin, R. & Kenolty, N. 1974. The Geology of the Sea of the Hebrides. Institute of Geological Sciences Report No. 73/14. 43 pp.
British Geological Survey. 1987. Argyll sheet 56°N–06°W, Solid Geology 1:250,000 Sheet. London: HMSO for the British Geological Survey.
Brown, C. J & Blondel, P. 2009. Developments in the application of multibeam sonar backscatter for seafloor habitat mapping. Applied Acoustics 70, 1242–47.
Cazenave, P. 2012. Past and Present Sediment Transport of the North-west European Continental Shelf. Unpublished PhD Thesis, University of Southampton.
Crump, P. 2013. Report of Survey, Hydrographic Instruction 1354: Inner approaches to the Firth of Lorn. UK Hydrographic Office.
Davies, H. C., Dobson, M. R. & Whittington, R. J. 1984. A revised stratigraphy for Quaternary deposits on the inner continental shelf west of Scotland, 55°30'N and 57°30'N. Boreas 13, 4966.
Dobson, M. R. & Evans, D. 1974. Geological structure of the Malin Sea. Journal of the Geological Society, London 130, 475–78.
Dyer, K. R & Huntley, D. A. 1999. The origin, classification and modelling of sand banks and ridges. Continental Shelf Research 19, 1285–330.
Eden, R. A., Ardus, D. A., Binns, P. E., McQuillin, R. & Wilson, J. B. 1971. Geological investigations with a manned submersible off the west coast of Scotland 1969–1970. Institute of Geological Sciences Report No. 71/16. 49 pp.
Fader, G. B. J. 1991. Gas-related sedimentary features from the eastern Canadian continental shelf. Continental Shelf Research 11, 1123–53.
Fader, G. B. J. 1997. The effects of shallow gas on seismic reflection profiles. In Davies, T. A., Bell, T., Cooper, A. K., Josenhams, H., Polyak, L., Solheim, A., Stoker, M. S. & Stravers, J. A. (eds) Glaciated Continental Margins: An atlas of acoustic images. London: Chapman and Hall. 315 pp.
Fyfe, J. A., Long, D. & Evans, D. 1993. The geology of the Malin-Hebrides sea area. London: HMSO for the British Geological Survey.
Hickman, A. H. 1975. The stratigraphy of late Precambrian metasediments between Glen Roy and Lismore. Scottish Journal of Geology 11, 117–42.
Holgate, N. 1969. Palaeozoic and Tertiary transcurrent movements on the Great Glen Fault. Scottish Journal of Geology 5, 97139.
Howe, J. A., Dove, D., Bradwell, T. & Gaferia, J. 2012. Submarine geology and glacial history. Marine Geology 315–318, 6476.
Judd, A. & Hovland, M. 2007. Seabed fluid flow; the impact on geology, biology and the marine environment. Cambridge: Cambridge University Press. 475 pp.
Li, M. Z., Shaw, J., Todd, B., Kostylev, V. E. & Wu, Y. 2013. Sediment transport and development of banner banks and sand waves in an extreme tidal system: Upper Bay of Fund, Canada. Continental Shelf Research 83, 86107.
Litherland, M. 1980. The stratigraphy of Dalradian rocks around Loch Creran, Argyll. Scottish Journal of Geology 16, 105–23.
McIntyre, K. L. 2012. Offshore records of late glacial ice extent and deglaciation, Loch Linnhe, western Scotland. Unpublished PhD Thesis, University of Aberdeen.
McIntyre, K. L & Howe, J. A. 2010. Scottish west coast fjords since the last glaciation: a review. In Howe, J. A., Austin, W. E. N., Forwick, M & Paetzel, M. (eds) Fjords, systems and archives. Geological Society, London, Special Publication 344, 305–29. London, Bath: The Geological Society.
Ó Cofaigh, C., Dunlop, P. & Benetti, S. 2012. Marine geophysical evidence for Late Pleistocene ice sheet extent and recession off northwest Ireland. Quaternary Science Reviews 44, 147–59.
O'Reilly, C. T., Solvason, R. & Solomon, C. 2005. Where are the World's Largest Tides? In Ryan, J. (ed.) Bedford Institute of Oceanography Annual Report 2004, 4446.
Shaw, J., Todd, B. J., Li, M. Z. & Wu, Y. 2012. Anatomy of the tidal scour system at Minas Passage, Bay of Fundy, Canada. Marine Geology 323–325, 123–34.
Stephenson, D. & Gould, D. 1995. British regional geology: the Grampian Highlands (4th edition). London: HMSO for the British Geological Survey.
Stoker, M. S., Bradwell, T., Wilson, C., Harper, C., Smith, D. & Brett, C. 2006. Pristine fjord land system revealed on the seabed in the Summer Isles region, NW Scotland. Scottish Journal of Geology 42, 8999.
Trewin, N. H. & Thirlwall, M. F. 2002. The Old Red Sandstone. In Trewin, N. H. (ed.) The Geology of Scotland, 4th Edition. London, Bath: The Geological Society. viii+576 pp.

Keywords

The seabed geomorphology and geological structure of the Firth of Lorn, western Scotland, UK, as revealed by multibeam echo-sounder survey

  • John A. Howe (a1), Roger Anderton (a2), Riccardo Arosio (a1), Dayton Dove (a3), Tom Bradwell (a3), Philip Crump (a1), Rhys Cooper (a3) and Andre Cocuccio (a4)...

Metrics

Altmetric attention score

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed