1893 E. A. Smith in Amer. Jrnl. Sci. 145 306 I..suggest the following terms, under fault, faulted under fold, underthrust fault, as applicable to this type of structure.

1908 H. B. C. Sollas & W. J. Sollas tr. E. Suess Face of Earth III. ix. 396 Holmquist concludes that, owing to the continuous subsidence of the eastern part (i.e. of the shield or foreland) the overthrusting practically becomes an underthrusting.

1931 Geol. Mag. LXVIII. 39 The front of the underthrust mass will be concave towards the direction of underthrusting.

1965 G. J. Williams Econ. Geol. N.Z. xix. 350/1 The south-east flank is steep and in places faulted or underthrust.

1971 I. G. Gass et al. Understanding Earth xix. 286 The major mountain chains..occur where moving plates collide and one underthrusts the other.

1977 A. Hallam Planet Earth 63/3 In general, the larger events—those with Richter magnitudes greater than 5 or 6—do not occur in regions of plate creation but are associated only with the more violent process of plate underthrusting.