▪ I. craton
see crathon.
▪ II. craton, n. Geol.
(ˈkrætɒn)
Also † kraton.
[f. kratogen n. with alteration of initial letter, perh. after crater n., etc.]
A large stable block of the earth's crust that has resisted deformation over a (geologically) long period of time; = kratogen n.
| 1935 tr. H. Stille in Research & Progress I. 10 In the Asiatic portion of the latter [sc. continental Eurasia] we observe the same process of continental growth as in Europe. Here too we have primordial craters [corrected (Ibid. 94) to cratons], such as ‘Angaraland’ in the centre of Northern Siberia..and also a ‘Paleo-Asia’. 1942 Bull. Geol. Soc. Amer. LIII. 1640 The Michigan basin..is a geosyncline defined by causes within its area; the latter [sc. the Allegheny belt] was depressed in complement to uplift near by... Both are within the craton or ‘shield’. 1970 Cambr. Anc. Hist. (ed. 3) I. i. i. 5 For these platforms incorporating remnants of past orogenic belts Stille invented the term ‘kraton’, of obscure etymology but considerable convenience. 1979 Sci. Amer. Jan. 70/2 Together the shields and platforms constitute the cratons, the stable blocks that are the nuclei of present-day continental masses. 1986 New Yorker 24 Feb. 39/3 Had this been a May morning a hundred million years ago,..we would have been many fathoms underwater, in a broad arm of the sea, which covered the continental platform—reached across the North American craton, the Stable Interior Craton—from the Gulf of Mexico to the Arctic Ocean. |
Hence craˈtonic a., of, pertaining to, or designating a craton.
| 1935 tr. H. Stille in Research & Progress I. 10 And so there arose at last the great craterous [corrected (Ibid. 94) to cratonic] ring ‘Peri-Arctis’. 1944 Science 9 June 462/2 The cratonal flexure of the Lower Pennsylvanian miogeosyncline lies west of the Adirondack line. 1971 I. G. Gass et al. Understanding Earth xxii. 320/2 All of these areas lie within the older cratonic regions of Africa. 1976 A. & L. Rittmann Volcanoes 120/1 Deposits of mercury, silver, gold, uranium and lead are derived from orogenic volcanism, and iron, copper, nickel, manganese and titanium from cratonic volcanism. 1991 Sci. Amer. May 54/1 Simultaneously, another type of ore deposit began to form in cratonal regions, the growth centers of continents. 1992 Earth Surface Processes & Landforms XVII. 339 This contradicts Fairbridge and Fiukl's suggestion that cratonic denudation rates are several orders of magnitude less than those of other areas. |