| 释义 |
synclinal, a. and n.|sɪnˈklaɪnəl, ˈsɪŋklɪnəl|
[f. Gr. σύν syn-1 + κλίνειν to bend + -al1.]
A. adj.
a. Geol. Applied to a line or axis towards which strata dip or slope down in opposite directions; also said of the fold or bend in such strata, or of a valley, trough, or basin so formed. Opposed to anticlinal.
1833Lyell Princ. Geol. III. 293 A series of anticlinal and synclinal lines, which form ridges and troughs running nearly parallel to each other. 1863Dana Man. Geol. §113. 105 A synclinal valley is a valley formed by strata sloping downward from either side. 1867Murchison Siluria viii. (ed. 4) 171 The extension of the..Silurian strata..by..synclinal folds. 1876Page Adv. Text-bk. Geol. xix. 376 The synclinal basins of London and Hampshire.
b. transf. and gen. Inclined or sloping towards each other, or characterized by such inclination.
1880B. E. Falkonberg Desert Life 320 Narrow avenues of airy palm-trees with their tops of synclinal fan-tracery. 1903A. M. Clerke Probl. Astrophysics i. xi. 126 Synclinal forms (as the petal-shaped structures are called) emerge in both, and the branching effusions round the trapezium seem to mimic details legible in many eclipse⁓pictures.
B. n. Geol. A synclinal line, fold, or depression.
1855J. Phillips Man. Geol. 142 The strata rising and falling in many steep anticlinals and deep synclinals. 1874Raymond Statist. Mines & Mining 512 The east shaft..has passed the synclinal and is now cutting through the south-dipping strata.
Hence or so synˈclinally adv., in the form of a synclinal fold; syncline |ˈsɪŋklaɪn|, a synclinal fold or depression; (see also quot. 1972); cf. synform s.v. syn-1 1; synˈclinical a. = synclinal a.; ‖ synclinorium |sɪŋklɪˈnɔərɪəm|, pl. -ia, anglicized synclinore |ˈsɪŋklɪnɔː(r)|, see quots.; whence syncliˈnorial, -ˈnorian adjs.
a1846Rogers in Worcester, Synclinical. 1855J. Phillips Man. Geol. 45 The strata are synclinally and anticlinally bent. 1873J. Geikie Gt. Ice Age xxi. 266 Diagrammatic view of synclines and anticlines. 1880Dana Man. Geol. (ed. 3) 821 The mountain range, begun in a geosynclinal, and ending in a catastrophe of displacement and upturning, is appropriately named a synclinorium... (The word is from the Greek for synclinal, and ὄρος, mountain). Ibid. 823 After the last mentioned synclinorial range [of mountains] was completed. 1883― Text-bk. Geol. 56 (Cent. Dict.) Synclinore. 1883A. Winchell World-Life (1889) 331 Geosynclinals are in progress beneath the sea, which will never attain synclinorian crises unless some revolution provides supplies of sediments. 1893B. Willis in 13th Ann. Rep. U.S. Geol. Surv. ii. 219 The two great types of folds are the syncline and the anticline. The syncline..is a depression of the strata from a flat to a basin-shaped form. 1937Trans. R. Soc. Edin. LIX. 81 In common tectonic practice, an anticline has come to be understood as a fold with a core of previously underlying rocks, and a syncline as a fold with a core of previously overlying rocks. 1972Gloss. Geol. (Amer. Geol. Inst.) 718/2 Syncline, a fold, the core of which contains the stratigraphically younger rocks; it is concave upward. |