SOUTH CHETICAMP, CAPE BRETON ISLAND. — GRANDIN. S59 



Galena. — "Galena," from a structural point of view is one of- 

 the most interesting and instructive of the L'Abime deposits. 

 It is situated in the L'Abime gorge about 900 feet below the 

 general level of the plateau and a mile N. N. E. of Iron Cap. 

 It consists of a ! ed of garnetiferous serecite schist (locally called 

 the " grey schist ") carrying galena associated with zinc blende 

 and arsenopyrite and outcropping in clifts on both sides of the 

 L'Abhne brook which here flows north-easterly. The schists 

 are at this deposit bent into a synclinal fold with characteristic 

 longitudinal and transverse undulations well developed. Several 

 openings have been made on the right bank of the brook which 

 facilitate the study of the structural features of the deposit. 

 At these openings the prevailing dip is approximately N. N. 

 W. at about 28". Overlying the " gi'cy " at the most westerly 

 opening (No. 1) is a hydromica schist of bluish color (locally 

 called the " blue schist ") which is seen at the next opening 

 towards the east to impinge upon and intertongue with the 

 " to^'sy " as the outcrop of the latter ascends the bank of the 

 brook. Higher up the bank, but stratigraphically lower than 

 it appears at No. 1 opening, the " grey " is seen intertongueing 

 with the " blue." Lower down the brook in the clifl' on the 

 left bank, fragments of the " grey " are seen intercalated among 

 the " blue." This faulted condition of the schists could only 

 have been caused b}'' a lateral thrust which broke and drove 

 the severed beds over their original continuation and forced 

 their jagged ends together. (See fig. 5.) 



The ore minerals are found hi lenses and veins in the " grey " 

 schist in much the same manner as they occur in the deposits 

 already described ; but at Galena they are also found deposited 

 in sheet-like masses along the thrust plane at the contact of 

 the " blue," and " grey " schists. They are also found occupy- 

 ing rents of a somewhat lenticular shape which cut through 

 the planes of foliation and which appear to have been formed 

 at the time the thrusting took place. 



