PREVIOUS RESEARCH 501 



In 1879 Dr T. Sterry Hunt discussed the structure of the region in 

 the American Geologist, under the title "The Quebec Group in Geology." 



In 1882 Dr A. E. C. Selwyn first outlined his views of the structure 

 and general lithology of the Quebec Group in an address before the Eoyal 

 Society of Canada.* 



In 1902 the present writer showed that important parts of the pre- 

 Cambrian are composed of volcanic rocks which by their extreme altera- 

 tion had been previously mistaken for sediments. Their relation to 

 other occurrences of similar rocks in the Appalachians was suggested and 

 their place in the series described by the late G. H. Williams was pointed 

 out.f 



• The pre- Cambrian copper-bearing Volcanics 



The physiographic structure of the Eastern townships, it has been 

 said, depends on three ridges of pre-Cambrian rock which are in the 

 form of rather narrow belts about 25 miles apart, running parallel to the 

 axes of the Appalachian mountains. These ridges which appear above 

 the intervening sediments and later intrusives are the crests of once 

 buried mountain ranges, now partially uncovered. Here and there out- 

 lying remnants of sedimentary rock still rest on them. 



One of the belts appears for only a relatively short distance along the 

 boundary line between the province of Quebec and the state of Maine. 

 It occurs in the townships of Emberton, Chesham, Clinton, Woburn, 

 Ditchfield, and Spalding. From its proximity to the lake of that name, 

 it may be designated the Lake Megantic area. 



The second crosses the Saint Francis river between the city of Sher- 

 brooke and the village of Lennoxville, and is commonly referred to as 

 the Ascot or Stoke Mountain belt. It may be traced from the foot of 

 Owlshead mountain and lake Memphremagog, through parts of the town- 

 ships of Stanstead, Hatley, Ascot, Ascot Corner, Stoke, Dudswell, Wee- 

 don, and Stratford. The similar rock at the Gilbert Eiver gold mines, 

 in the seigniory of Delery, on the east side of the Chaudiere river, un- 

 doubtedly belongs to this belt. 



The third of these belts, which crosses the Saint Francis river near the 

 town of Eichmond 25 miles northwest of the last, is generally known as 

 the Sutton Mountain belt. This is the largest and longest of the three, 

 as far as is at present known. While the Stoke belt is nowhere more than 

 5 miles in width, that of Sutton is quite 20 miles wide at the Vermont 



* Transactions of the Royal Society of Canada, 1882. 



f Transactions of the Canadian Mining Institute, Montreal, March 12, 1902. 

 American Journal of Science, July, 1902. 



