What lies beneath Rockall?
Rockall, a tiny island not much bigger than a house, sits on the very extremity of Scotland’s marine environment. Some 180 miles due west of St. Kilda, it is buffeted year round by the extreme winds and swell that the North Atlantic weather generates. As such, it is Scotland’s only truly offshore shallow water ecosystem. The islet of Rockall is actually one tiny part of vast plateau of continent that was submerged beneath the Atlantic millions of years ago. During the last glaciation, when sea-level was lower, a number of islands would have formed a small archipelago out there.
In recent years Marine Scotland explored and mapped the areas around the islet of Rockall; using MRV Scotia’s high resolution ‘swathe’ or multibeam echosounder. This technology allows the seabed to be mapped to within a few metres of spatial resolution. A huge amount of data were generated and after much processing back at the lab, a bathymetric map has now been produced.
Using 3D visualisation software, it is possible to ‘fly-over’ the numerous previously uncharted pinnacles, trenches, mounds, ridges and reefs that surround Rockall. The Rock itself turns out to be a relatively minor feature compared with Helen’s reef to the east, that extends in a great sweeping arc. Rockall and Helen’s reef have been the site of many a shipwreck in the past and we have had enquiries from the public interested in finding wrecks in the area.
So far the data have not revealed anything obviously man-made lying on the seabed, but the map is now available for anybody to examine in detail and will become a feature of National Marine Plan Interactive (NMPi) in due course.