| 释义 |
varve|vɑːv|
[ad. Sw. varv layer, turn.]
A pair of thin layers of clay and silt of contrasting colour and texture which represent the deposit of a single year (summer and winter) in still water at some time in the past (usu. in a lake formed by a retreating ice-sheet); they have been used to establish a chronology of the late glacial and post-glacial period. Also attrib. and Comb. Hence varved |vɑːvd| a., characterized by such layers.
[1887Encycl. Brit. XXII. 740/1 The glacial clay consists generally of..darker and lighter coloured layers, which give it a striped appearance, for which reason it has often been called hvarfvig lera (striped clay).] 1912G. De Geer in Compt. Rend. XI Session Congrès Géol. Internat. 253 The Swedish word varv, subst. (old spelling: hvarf), means as well a circle as a periodical iteration of layers. An international term for the last sense being wanted it seems suitable to use the transcription varve, pl. -s, in Engl. and Fr. 1929C. R. Longwell Pirsson's Textbk. Geol. (ed. 3) I. v. 126 Lake Deposits.—Remarkably banded clays have been formed in patches within the glaciated regions... The Swedish geologists call them varved clays. 1936Times Lit. Suppl. 9 May 392/2 Varve⁓variation in its general features is a function of solar radiation. 1948Bull. Geol. Soc. Amer. LIX. 646 In this basin (Fossil, Wyo.) hundreds of thousands of beautifully preserved fish are entombed in the varved sediments. 1953Antiquity XXVII. 35 What we most need now, apart from archaeology, is a study of the post-glacial climatic fluctuations in the Tigris and Euphrates valleys. Here the techniques of Western Europe, such as pollen analysis and varve-counting, seem unlikely to be of any use. 1957G. E. Hutchinson Treat. Limnology I. i. 8 The dating of the events, based primarily on the varve chronology, is in fair accord with the radiocarbon chronology. 1974Nature 15 Nov. 182/1 The thickness of the varves..provide [sic] a guide to the year-by-year changes in mean climate; but that is at best a crude measure. |