| 释义 |
Laurasia Geol.|lɔːˈreɪʃ(ɪ)ə|
[mod.L. (R. Staub Der Bewegungsmech. der Erde (1928) ii. 121), f. Laur(entia, name given to the ancient forerunner of N. America (from the Laurentian strata of the Canadian Shield by which it is represented today) + Eur)asia (see Eurasian a. 1).]
A vast continental area or supercontinent thought to have once existed in the northern hemisphere and to have broken up in Mesozoic or late Palæozoic times forming North America, Greenland, Europe, and most of Asia north of the Himalayas. Also, these land masses collectively as they exist today.
1931Trans. Geol. Soc. Glasgow XVIII. 578 The long history of the Tethys girdling the continental shelf of the earth between Gondwanaland and Laurasia is a clear indication of the operation of some opposing force tending to pull the continents apart. 1937A. L. Du Toit Our Wandering Continents ii. 24 Through..alternating ‘polar flight’ and ‘polar drift’ Laurasia and Gondwana have successively impinged upon or else parted from one another. 1944A. Holmes Princ. Physical Geol. xvii. 367 The [earthquake] belts form two rings..: one enclosing North America and most of Asia and Europe (known collectively as Laurasia), and the other enclosing South America, Africa and Arabia, India, Australia, and Antarctica (known collectively as Gondwanaland). 1971I. G. Gass et al. Understanding Earth xv. 229 Gondwanaland..probably formed about 500 million years ago, and Laurasia, west of the Urals, about 370 million years ago. 1974Daily Tel. (Colour Suppl.) 10 Apr. 20/1 Whether Laurasia and Gondwanaland were themselves joined together into a supercontinent is a question still to be resolved.
Hence Lauˈrasian a.
1962L. C. King Morphol. Earth xii. 399 At the beginning of Cretaceous time virtually the whole of the vast continental interior had been reduced to a landscape of low relief—the Laurasian surface. 1973Nature 1 June 278/2 The Atlantic and Indian Oceans originated from the break up of the Gondwanan and Laurasian continents. |