| 释义 |
palæoˈmagnetism Geol.
Also (chiefly U.S.) paleo-.
[f. palæo-, paleo- + magnetism.]
(The study and interpretation of) the natural magnetism of rocks, which they are believed to have acquired at the time of their formation and is used as evidence for the past relationship of the rocks to each other and to the earth's magnetic field.
1854Edin. New Philos. Jrnl. LVI. 9 The palæomagnetism..will also give rise to most interesting discoveries, and even to magnetical maps in the various geological periods. 1953T. Nagata Rock-Magnetism vi. 213 Other people might be concerned with rock-magnetism as the medium or the fossil of the geomagnetic field in the past geologic times, namely, as the tool for palaeomagnetism, since the knowledge of the secular variation of geomagnetic field throughout the whole life of the earth is one of the basic subjects in the modern geophysics. 1955Nature 10 Sept. 505/1 (heading) Palæomagnetism of sediments from the Colorado Plateau. 1962Listener 17 May 849/1 This new subject of palaeomagnetism enables us to track the movement of the magnetic poles relative to the continents. 1970Nature 6 June 934/1 The motion of these plates with respect to the Earth's spin axis can be determined using the methods of palaeomagnetism. 1971I. G. Gass et al. Understanding Earth xv. 222/2 One may use palaeomagnetism as a tool for verifying continental drift.
Hence ˌpalæomagˈnetic a., of or pertaining to palæomagnetism; ˌpalæomagˈnetically adv., by means of or as regards palæomagnetism; palæoˈmagnetist, one who studies palæomagnetism.
1953T. Nagata Rock-Magnetism vi. 218 It seems that the Königsberger's [sic] conclusion quoted above is still substantially right at present and very useful as the criterion of available rock-magnetism for the palaeo⁓magnetic purposes. 1957Adv. Physics VI. 166 Drab deltaic sediments of a cool environment are palaeomagnetically unsuitable. 1960Bull. Geol. Soc. Amer. LXXI. 763/2 The paleomagnetist would like to know if it is at all possible for a nonaxial dipole field to exist for a long period of time. 1969Bennison & Wright Geol. Hist. Brit. Isles iii. 51 As well as the marked angular unconformity, there is a difference in the palaeomagnetic pole position of about 50° which may indicate that this part of the Lower Torridonian is much older than the upper groups. 1970New Scientist 17 Dec. 491/1 A stern criticism which palaeomagnetists have always had to face..is over the long-term stability of the magnetic minerals within their rock samples. 1973Nature 23 Feb. 497/2 It is not difficult to distinguish palaeomagnetically between polar wandering and continental drift if one or the other acts alone. 1977A. Hallam Planet Earth 143 Paleomagnetic studies have been vital in establishing the theory of plate tectonics. |