4 R. T. CHAMBERLIN AND W. Z. MILLER 
In the southern Appalachian Mountains the Rome and Carters- 
ville overthrusts run parallel to each other for over 200 miles. They 
are thought by Hayes to show horizontal displacements of not less 
than 4 miles and 11 miles respectively, and possibly much more. 
The inclination of the fault planes is here frequently as low as 5°; 
it is rarely more than 25°.1 The steeper portions of the plane as now 
seen are largely the result of subsequent warping. Farther north, in 
Tennessee, a possible continuation of the Cartersville thrust is the 
Buffalo Mountain fault which, according to Keith, was a low- 
angle overthrust whose original displacement along the shear plane 
was at least 20 miles.? Subsequent folding and faulting have so 
disturbed this fault plane that its original inclination cannot be 
very closely determined. 
More to the north, the earlier Taconic revolution also developed 
low-angle overthrusts. Of these may be noted the Great Western 
fault of eastern New York,’ the St. Lawrence and Champlain fault, 
which runs from Vermont to the city of Quebec and beyond,’ and 
possibly the Cowansville overthrust of Missisquoi and Brome 
counties, Quebec, though the age of the last has not been closely 
determined as yet. In any case the measured horizontal displace- 
ment of the last is 11 miles, and it is thought likely that the actual 
displacement was much greater.’ It is a nearly horizontal over- 
thrust, whose plane is very close to the present surface, and along 
which the Georgian slates on the east have been shoved over the 
Trenton slates and limestones of the Farnham series to the west. 
The Rocky Mountains of Montana and Alberta are bordered on 
their eastern front, throughout at least 350 miles of their extent, 
tC. W. Hayes, “‘The Overthrust Faults of the Southern Appalachians,” Bull. . 
Geol. Soc. Amer., II (1891), 141-54. 
2 Arthur Keith, U.S. Geol. Surv. Geol. Atlas, Roan Mountain (Tenn.), Folio 151, 
1907, P. 9- 
3 James D. Dana, Manual of Geology (4th ed.), 1895, p. 528; S. W. Ford, ‘“Obser- 
vations upon the Great Fault in the Vicinity of Schodack Landing, Rensellaer County, 
N.Y.,” Am. Jour. Sci., XXIX (1885), 16-19. 
4G. A. Young, ‘“‘The Geology and Petrography of Mount Yamaska, Province 
of Quebec,” Geol. Surv. Can. Ann. Rept., XVI (1906), 9. 
5 Robert Harvie, “‘Brome and Missisquoi Counties, Quebec,” Sim. Repi., Geol. 
Surv. Can., 1914, pp. 98-99. i 
