Also 9 up-throe. [UP- 2. Cf. next.]
1. Geol. and Mining. An upward dislocation of a stratum or seam.
1807. J. Headrick, View Arran, 66. A high rock, caused by what is called an up-throe of the metals. Ibid. This upthroe running westward, forms a sort of ridge.
1883. [see UPLEAP sb. 2].
1888. J. Prestwich, Geol., II. 95. An elevation of the strata on one side, and … depression on the other, which are called by the miners the upthrow and the downthrow.
attrib. 1839. Ure, Dict. Arts, 965. Dikes and faults are denominated upthrow or downthrow, according to the position they are met with in working the mine.
1872. Proc. Amer. Philos. Soc., XII. 444. A fine upthrow fault … in East Tennessee.
1882. Geikie, Geol. Sk., 282. A true fault with an upthrow and downthrow side.
b. Amount of upward displacement.
1889. Hardwicke’s Sci. Gossip, XXV. 228/1. A small fault, with five feet upthrow.
2. Geol. An upheaval of part of the earth’s crust or surface; an uplift.
1833. Lyell, Princ. Geol., III. 333. The sudden upthrow of another system of parallel chains of mountains.
1863. Dana, Man. Geol., 727. By the upthrow, rocks of the Lower Silurian have been carried up to the level of those of the Subcarboniferous.
1884. Geikie, in Nature, 13 Nov., 31. In the great upthrow, it is this sandstone platform which has been pushed over the limestones.
3. An outburst or manifestation.
1855. M. Pattison, in Oxford Ess., 274. The Wycliff movement,… that last upthrow of Latin philosophy.
4. The action of throwing up or casting upwards.
1898. Daily News, 23 Sept., 2/3. The up-throw with which a marksman jerks his rifle from his shoulder after a successful shot.
