| 释义 |
phacolith Geol.|ˈfækəʊlɪθ|
[Alteration of prec.: see -lith.]
An intrusive mass of igneous rocks situated between consecutive strata at the top of an anticline or the bottom of a syncline.
1910Lake & Rastall Text-bk. Geol. xiii. 225 These long narrow intrusions are called by Mr. Harker phacolites (more correctly phacoliths). 1947S. J. Shand Study of Rocks (ed. 2) ii. 16 The phacolith might be described as a saddle-shaped laccolith;..but there is this important difference between a laccolith and a phacolith that the former is the cause of the folding of its country rocks while the latter is a consequence of folding. [Ed. 1 (1931): phacolite, laccolite.] 1971B. W. Sparks Rocks & Relief iii. 93 Laccoliths are approximately circular, but phacoliths are not, except in the rare case of their being formed in a dome. Usually they are elongated in the direction of the axes of the folds. 1977A. Hallam Planet Earth 68 Phacoliths are curved sill-like intrusions emplaced in the crests and troughs of folded rocks. |