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1906 H. B. C. Sollas & W. J. Sollas tr. E. Suess Face of Earth II. iii. ii. 30 The whole of the north-east of America, from the mouth of the St. Lawrence to that of the Mackenzie..belongs to a broad table-land of horizontal Palaeozoic beds, from beneath which the Archaean foundation crops out in the middle of the table-land not unlike a flat shield. This Archaean shield is thus surrounded by a ring of horizontally stratified sediments... It is to the exposed Archaean surface that we give the name of the Canadian shield.

1906 H. B. C. Sollas & W. J. Sollas tr. E. Suess Face of Earth II. iii. ii. 76 East of the glint lies the Archaean table-land of the gulf of Bothnia; that is, the Baltic shield.

1915 C. Schuchert Text-bk. Geol. II. xxi. 461 Most of the present continents have been formed around ancient protuberances of the lithosphere, the nuclear lands or shields.

1939 A. K. Lobeck Geomorphol. i. 4 Suess showed that certain substantial areas of the earth have always been rigid and unyielding, as, for example, the Canadian and Baltic Shields of America and Europe, the eastern Siberia Shield of Asia, [etc.].

1963 D. W. Humphries & E. E. Humphries tr. H. Termier & G. Termier Erosion & Sedimentation ii. 40 The ancient shields, which are also called ‘old platforms’, are none other than peneplains which have almost attained a final form.

1968 Beaver Autumn 14/1 He was with the voyageurs somewhere out in the bush covering some historic route over the Shield.

1969 G. M. Bennison & A. E. Wright Geol. Hist. Brit. Isles iii. 41 Before the break up of the continents the Lewisian rocks were probably contiguous with the Canadian-Greenland shield, one of the original continental cores.

1971 I. G. Gass et al. Understanding Earth iii. 55/1 The oldest continental regions, the Precambrian Shields, are often dominated by igneous rocks such as granite or by highly metamorphosed rocks such as gneiss.