48 



what are regarded as tlie Lower Cambrian quartzltes and slates of that 

 area. 



Briefly spealiiiig, the structure of the nietamorphic rocks of 

 south-eastern Quebec may be said to consist of a series of approximately 

 parallel ridges or antic! inals of Pre-Cambrian age, of which at least 

 three have been definitely located. The most easterly of these is found 

 along the boundary between Maine and the eastern limit of the Prov- 

 ince, the middle is seen in the Htoke Mountain range and its expansion 

 south-westerly to Lake Memphremagog, while the third constitutes the 

 Sutton Mountain range and its prolongation to the north-east through 

 the Province to Gaspe. 



The intervals between these ranges are occupied by overlying sedi- 

 ments, mostly sandstones and slates of various colors, which, in places, 

 are fossiliferous, and are now regarded and described in the Geological 

 Report for 188G as of Cambrian and Cambro-Silurian age. With these 

 are associated areas, often of large size, of diorites, serpentines and 

 granitic rocks. At several points, also, small, isolated and, at times, 

 closely infolded basins of fossiliferous Silurian strata are observed. 

 Between the most westerly of the old ridges and the St. Lawrence 

 River the country is apparently occupied to a very large extent by rocks 

 of Cambro-Silurian and Upper Cambrian age, much of which constitute 

 what has for many years been regarded as the unaltered portion of the 

 Quebec group, while the newer portion or that nearest the river is 

 characterized, throughout a large extent, by fossils of the Hudson River 

 and Utica formations. 



The mineral wealth of this portion of Quebec is confined, for the 

 most part, to the older systems, viz., the Pre-Cambrian and Cambrian, 

 and though traces of various ores are occasionally found in the newer, 

 in no case yet observed do these occur in quantity sufficient to be of 

 economic value. Thus the workable deposits of copper ore exist princi- 

 pally in the Pre-Cambrian schists, though they have been located and 

 worked, to a limited extent, in rocks of the overlying system. The ores 

 of iron are found also mostly in the lowest series, and when found in 

 the upper are largely confined to the volcanic portion, sometimes in the 

 serpentines where veins often of large size occur. The gold, which, 

 however, has not as yet beon worked except as an alluvial deposit, pre- 



