[ 89 1 



IV. — Notes on the Geology of the North Coast of the St. Lawrence. 



By Capt. BAYFIELD, R.N. F.R.A.S. 

 Communicated by G. B. Greenough, Esq. P.G.S. 



[Read Nov. 20th, 1833.] 



1 . On presenting- a suite of specimens to the Geological Society from a long- 

 line of coast, which is scarcely more known in Canada than in Europe, being 

 seldom visited except by fur traders and fishermen, I hope a few remarks upon 

 the structure of the country, will not be deemed devoid of interest, though my 

 official duties did not allow of a minute investigation. 



The district between Quebec and the river Saguenay, particularly about 

 Murray Bay, has been examined by Dr. Bigsby. The late William Green, 

 Esq. has most ably described the vicinity of Montmorency* ; and Lieut. 

 Baddeley of the Royal Engineers, St. Paul's bay and the Saguenay riverf 

 with a minuteness and ability which leave me nothing to add. I shall there- 

 fore commence my account at the Saguenay, and proceeding eastward, de- 

 scribe the coast of the river and Gulf of St. Lawrence.;}; 



2. From the Saguenay to Pointe de Monts, a distance of 130 nautical miles §, 

 the hills forming the coast are composed, for the greater part, of varieties of 

 syenitic granite ; and the country inland as far as the Falls of the Bersimis 

 river, about 40 miles from the St. Lawrence, in a direction parallel, or nearly 

 so, to the course of the Saguenay, consists of the same formation. 



All the valleys and basins between the granitic hills are filled with horizon- 

 tally stratified deposits of clay, sand and gravel, sometimes 200 or 300 feet 

 thick ; the clay being invariably next the granite, and the gravel generally on 

 the surface. No organic remains having been found, it is difficult to assign to 

 these deposits any relative ageT; but as the rivers, tributary both to the St. 

 Lawrence and the Saguenay, have cut sections through them, future investi- 



* Transactions of Literary and Historical Society of Quebec, vol. i, p. 181. 

 t Ibid.vol.i.p. 79. vol. ii. p. 76. | Plate V. fig. 1. 



§ The distances in this memoir always mean nautical miles. 



% Shells of species, existing at present in the estuary of the St. Lawrence, have been found in 

 tanks of similar sand and clay, as will be noticed hereafter (p. 96.). 

 VOL. V. SECOND SERIES. N 



