Abstract
Glacicl erosion is universally attributed to two processes — abrasion and plucking — and though satisfying explanations in physical terms have yet to be offered of the mechanics of either, their reality and their general characteristics are not in doubt. Abrasion is self-evidently witnessed by polished and striated surfaces, by fluting and streamlining and by such distinctively original forms of ice-moulding as roches moutonnées. Plucking is evidenced in a variety of ways. There is G. K. Gilbert’s (1910) argument that in southern Alaska where there is clearly evidence ‘of an enormous amount of glacial degradation, it was a matter of surprise to find the reduction of the surface to smooth sweeping curves was a somewhat rare phenomenon. By far the greater number of exposed glaciated areas, even where degradation has been profound, abound in low embossments and in more or less angular groins or re-entrant spaces showing little trace of abrasive action.’ This is equally true elsewhere. There is J. P. Dana’s argument (cited in Gilbert, 1910, p. 207) that the blocks and boulders in the moraines of the Laurentide ice sheet, which received no falling stones from mountain peaks, must have been plucked bodily from the underlying bed. In Britain this argument is best exemplified by the blocks of Silurian grit that have been torn from the floor of Crummack Dale and carried uphill to rest on the limestone scar that overlooks the Craven fault. But plucking has its most conspicuous results in the cliffs of conies, though as late as 1896 E. Richter thought that because such cliffs show no signs of abrasion they were not glacially sculptured but fashioned by frost weathering above the surface of the ice.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Eidg. Landestopographie, Aletschgletscher, 1 /10, 000, Blatt 3 (Wabern-Bern, 1960 ).
Battey, M. H. (1960) ‘Geological factors in the development of Veslgjuvbotn and Vesl-Skautbotn’, in W. V. Lewis (ed.), Investigations on Norwegian Cirque Glaciers, Royal Geographical Society Research Series No. 4, 11–24.
Dana, J. P., cited in G. K. Gilbert, op. cit., 207.
Davis, W. M. (1900) ‘Glacial erosion in France, Switzerland and Norway’, Proc. Boston Soc. Nat. Hist., xxcx 273–322.
Davis, W. M. (1912) Die erklärende Beschreibung der Landformen (Leipzig) Figs. 151–5.
Fairchild, H. L. (1907) ‘Drumlins of central western New York’, New York State Museum Bulletin, cxi 391–443.
Gilbert, G. K. (1910) Harriman Alaska Series vol. m: Glaciers and Glaciation.
Groom, Gillian E. (1959) ‘Niche glaciers in Bünsow Land, Vestspitzbergen’, Journal of Glaciology, nt 368–76.
Hobbs, W. H. (1911) Characteristics of Existing Glaciers (New York).
HoLtedahl, O. (1929) ‘On the geology and physiography of some Antarctic and sub-Antarctic islands’, Scientific Results, Norwegian Antarctic Expedition, nI 146–68.
JoHNsoN, Willard D. (1904) The profile of maturity in alpine glacial erosion’, Journal of Geology, xn 569–78.
Lewis, W. V. (1947) ‘Valley steps and glacial valley erosion’, Transactions and Papers, Institute of British Geographers, xiv 19–44.
Linton, D. L. (1949b) ‘Watershed breaching by ice in Scotland’, Transactions and Papers, Institute of British Geographers, xvi 1–16.
LinrnN, D. L. (1957) ‘Radiating valleys in glaciated lands’, Tädschrift van het Koninklijke Nederlandsche Aardrijkskundig Genootschap, Lxxiv 297–312.
LnvToN, D. L. (1962) ‘Glacial erosion on soft-rock outcrops in central Scotland’, Biuletyn Peryglacjalny, xi 247–57.
Nye, J. F. (1952) ‘A comparison of the theoretical and measured long profile of the Unteraar glacier’, Journal of Glaciology, n 103–7, Fig. 1 (based on P. L. Mercanton and A. Renaud, in works cited by Nye).
Parthasarathy, A., and Blyth, F. G. H. (1959) ‘The superficial deposits of the buried valley of the river Devon near Alva, Clackmannan, Scotland’, Proceedings of the Geologists’ Association, Lxx 33–50.
Richter, E. (1896) ‘Geomorphologische Beobachtungen aus Norwegen’, Sitzungsberichte der Wiener Akademie Math.-Naturw., cv 152–64.
Schroeder, H. (1928) Erläuterungen zur geologischen Karte von Preussen, Blatt Halberstadt, 2307.
Soons, Jane M. (1957) ‘The geomorphology of the Ochil hills’, unpublished Ph.D. thesis, University of GIasgow, 114–17.
StrÖM, K. M. (1949) ‘The geomorphology of Norway’, Geographical Journal, cxn 19–27.
Wooldridge, S. W., and Linton, D. L. (1955) Structure, Surface and Drainage in South-east England (London).
Editor information
Copyright information
© 1972 Macmillan Publishers Limited
About this chapter
Cite this chapter
Linton, D.L. (1972). The Forms of Glacial Erosion. In: Embleton, C. (eds) Glaciers and Glacial Erosion. The Geographical Readings series. Palgrave, London. https://doi.org/10.1007/978-1-349-15480-7_9
Download citation
DOI: https://doi.org/10.1007/978-1-349-15480-7_9
Publisher Name: Palgrave, London
Print ISBN: 978-0-333-12656-1
Online ISBN: 978-1-349-15480-7
eBook Packages: Earth and Environmental ScienceEarth and Environmental Science (R0)