| 释义 |
ˈdownfold Geol.
A synclinal fold or depression. So ˈdown-folded a., (of strata) dipping on each side towards a common axis.
1902H. J. Mackinder Britain & Brit. Seas vi. 71 To the very top it consists of down-folded beds. Ibid. 80 Geographical valley and geological downfold here coincide with a precision that is rare. 1920Glasgow Herald 15 Oct. 7 The oil did not come from the arches or anticlines, but from the down folds, (synclines). 1954J. F. Kirkaldy Gen. Princ. Geol. ii. 25 Stratified rocks..are often seen to be folded into upfolds (anticlines) and downfolds (synclines). 1970Sci. Amer. Feb. 37/2 The blocks of faulted crust in the lower part of the escarpment are tilted..in the direction opposite to what would be expected in a downfold. |