Abstract
The last two decades have witnessed a continually expanding programme of investigation concerned with the discovery of terrestrial impact craters or ‘astroblemes’ as Dietz has called them. These are the wounds produced on the Earth's surface by the high speed collisions with giant meteorites which have taken place throughout geological time. With the exception of a few comparatively recent craters, most of the large scars originated tens or hundreds of millions of years ago and have been preserved as ‘fossils’ in rocks which have since undergone considerable erosion and alteration.
Although various workers have now gathered an impressive array of evidence appertaining to the topographical, petrological and mineralogical changes wrought by the sudden release of enormous quantities of energy when collisions occur, it still remains true that most discoveries of craters are made as a result of their quasi-circular appearance on maps or aerial photographs.
A search of maps of the British Isles has revealed several possible impact sites, of which the most convincing is the feature known as St. Magnus Bay in the Shetland Islands. No explanation other than massive impact seems able to account for the peculiar shape of the bay and its resemblance to certain ancient Canadian impact crater residuals.
In size it ranks among the dozen or so largest terrestrial impact features and is thus an important object for further study; in its own right and in the context of the currently enhanced speculation concerning the origin of craters on such bodies as the Moon and Mars.
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References
Baldwin, R. B.: 1963,The Measure of the Moon, University of Chicago Press, p. 137; 170.
Beals, C. S., Innes, M. J. S., and Rottenberg, J. A.: 1963, ‘Fossil Meteorite Craters’, inThe Solar System. IV (ed. by B. M. Middlehurst and G. P. Kuiper), University of Chicago Press, pp. 235-284.
Beals, C. S.: 1964,Meteoritics 2, 2.
Beals, C. S. and Halliday, I.: 1967, ‘Terrestrial Meteorite Craters and Their Lunar Counterparts’, inInternational Dictionary of Geophysics, Pergamon Press, Oxford, Vol. 2, pp. 1520–1530.
Bunch, T. E. and Short, N. M.: 1968, ‘A Worldwide Inventory of Features Characteristic of Rocks Associated with Presumed Meteorite Impact Structures’, inShock Metamorphism of Natural Materials (ed. by French, B. M. and Short, N. M.), Mono Book Corp., Baltimore, pp. 255–266.
Dence, M. R.: 1969, Personal communication.
Dence, M. R., Inner, M. J. S., and Beals, C. S.: 1965,R.A.S.C.J. 59, 13–22.
Dence, M. R., Innes, M. J. S., and Robertson, P. M.: 1968, ‘Recent Geological and Geophysical Studies of Canadian Craters’, inShock Metamorphism of Natural Materials (ed. by French, B. M. and Short, N. M.), Mono Book Corp., Baltimore, pp. 339–363.
French, B. M. and Short, N. M. (eds.): 1968,Shock Metamorphism of Natural Materials, Mono Book Corp., Baltimore, pp. 2; 59-83; 347-48 etc.
Halliday, I. and Griffin, A. A.: 1963, ‘Evidence in Support of a Meteoritic Origin for West Hawk Lake, Manitoba, Canada’,J. Geophys. Res. 68, 5297–5305.
Mc. Quillin, R. and Brooks, M.: 1967, ‘Geophysical Surveys in the Shetland Isles’ (H.M.S.O.), p. 21.
Nininger, H. H.: 1952,Out of the Sky, Dover Publications, Inc., New York, pp. 230–234.
Peach, B. N. and Horne, J.: 1879, ‘The Glaciation of the Shetland Islands’,Quart. J. Geol. Soc. London 35, 778.
Sharp, A. W.: 1969, ‘The Moon's Mascons’,New Scientist, London,41 680.
Wilson, G. V.et al.: 1929-34, ‘Summaries of Progress of the Geological Survey of Great Britain’, H.M.S.O. London.
Wilson, G. V. and Knox, J.: 1936, ‘The Geology of the Orkney and Shetland Islands’,Proc. Geol. Assoc. 47, 270.
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Sharp, A.W. St. Magnus Bay, Shetland: A probable British meteorite crater of large size. The Moon 2, 144–156 (1970). https://doi.org/10.1007/BF00561958
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DOI: https://doi.org/10.1007/BF00561958