[MAi-THEw] GEOLOGICAL CYCLES IN MARITIME PROVINCES 129 



The comparison of the Lower lluronian terrane in western Nova 

 Scotia and southern New Brunswick shows a considerable resemblance 

 m the sedimentation : — 



Nova Scotia. New Bkunswick. 



1. Quartzite, some clay slate. 1. (jii'ay granitoid grits and much 



gray slates, 5,000 feet. 



2. Green, gray, purple and blu- 2. Gray clay slates and dark pur- 



ish gray slates, the latter with pie slates, 2,000 feet, 



conspicuous banding. The 

 two divisions 6,000 ft.) 



3. Black, with some blue and gray 3. Dark gray and gray clay slates, 



slates, vei-y rusty- weathering and gray feldspathic slates, 



3,000 feet. about 3,000 feet. 



The coarser condition of No. 1 (the lower division) in New Bruns- 

 wick may be due to the closer proximity of an emerged area of granitic 

 rocks of an earlier period, such as would have been afforded by the 

 Laurentian rocks described on the preceding page. To such a source 

 also may be ascribed the interraned conglomerates of this system ]ft 

 New Brunswick, which are so singularly absent from the corresponding 

 rocks of Nova Scotia. 



In northern Nova Scotia, in Pictou and Antigonish counties, are 

 bodies of fine flinty, dark slates and other elastics which on the 

 maps of Geological Survey are ascribed to a Cambro-Silurian (= Ordo- 

 vician) age, apparently because they underlie (unconformably) the recog- 

 nized Silurian (Upper) of the Arisaig Section. These, I think, are to 

 be regarded as a deep-water phase of the Huronian or Megirtn-a Series. 



On a succeeding page it will be shown that the Cambrian System in 

 these provinces is part of a closed geological cycle that includes the lower 

 Ordovician, and it is impossible to recognize in these so-called Cambro- 

 Silurian strata of northern Nova Scotia, the succession of Cambrian 

 strata that is so clearly seen in New Brunswick and Cape Breton. The 

 age of these strata in northern Nova Scotia has not been determined 

 by the evidence of fossils, and, in fact, there are no fossils of this Age 

 (Ordovician) known for hundreds of miles to the north and west of 

 this area, other than those that occur in connection with recognized 

 Cambrian areas. It appears more natural then, to assume that these 

 fine-grained, dark, flinty rocks should be assigned to the lower Huronian 

 as a deep-water phase of the same. 



This set of beds has been designated by Mr. Hugh Fletcher, of 

 the Canadian Geological Survey, as "The Lower Flinty slates 



Sec IV., 1908. 9. 



