macroseism Geol.
(ˈmækrəʊsaɪz(ə)m)
[f. macro- + seism.]
A major earthquake; in mod. use (rare), any earthquake, as opposed to an imperceptible earth tremor (cf. microseism).
| 1903 Sci. Amer. Suppl. 2 May 22855 Prof. Milne pointed out the distinction which exists between macroseisms, or large earthquakes, and microseisms, or small earthquakes. The former he described as world-shaking disturbances. 1907 Jrnl. Geol. XV. 401 Great confusion exists because of the different uses of the terms ‘macroseism’ and ‘microseism’, as well as the adjectives derived from them. The usage here is that of both Milne and de Montessus, which makes ‘macroseism’ apply to the greater disturbance on the ground. 1924 Bull. Seismol. Soc. Amer. XIV. 29 Various useful compounds [of seism] have been suggested, such as..macroseism, de Montessus, 1907, for an ordinary sensible earthquake. 1972 Gloss. Geol. (Amer. Geol. Inst.) 424/1 Macroseism, a syn. of earthquake, as opposed to microseism. |
Hence macroˈseismic a., of or pertaining to a macroseism or (in mod. use) those effects of an earthquake that are perceptible without the aid of instruments; macroˈseismically adv.
| 1903 Nature 9 July 235/1 This is probably true for other phases of motion, and it has also been shown to exist for macro-seismic disturbances. 1907 Jrnl. Geol. XV. 408 Macroseismic origins. 1938 Nature 1 Oct. 624/1 The region over which the shock was felt macroseismically extended as far as the island. 1940 Ibid. 6 Jan. 14/1 On the basis of the macroseismic data, the accompanying sketch map showing the isoseismal lines has been constructed. 1947 K. E. Bullen Introd. Theory Seismol. xv. 252 Macroseismic data..usefully supplement the data obtained from seismographs. 1973 Nature 17 Aug. 384/2 Fairly complete pictures of what are now termed the macroseismic aspects of Britain's larger earthquakes. |