66 McKELLAE ON THE ANIMIKIE AND 



ined the Auimikie beds on the south side aud the Huroniau folded schists on the north 

 side of the Saganaga Lake granite. This belt of folded schists is about six miles in width 

 extending to the other side of Saganaganse Lake, where fifteen miles, or so, of gneiss and 

 granite come in, separating tjiis belt from the Jackfish Lake Huronian belt. The flat 

 Animikie beds on the one side, and the Hnrouian folded schists on the other, of the Saga- 

 naga granite are as distinctly different in aspect, aud in the strata composing them, as 

 where they are separated by a hundred miles. I cannot believe it possible that there can 

 be a transition from the one to the other. 



LiTHOLOGicAL FEATURES. — In regard to the lithological features, I consider the two 

 formations distinctly different, as much so as could be expected of two partially meta- 

 morphosed series of rocks. The Huronian are much more altered than the Auimikie. 

 Not only are the sedimentary portions of the formations widely different, but also the 

 eruptive masses associated with each. The only eruptive rock found with the Animikie 

 beds is a dark-grey crystalline trap ; which, in one of the thin beds east of the Thunder 

 Bay Mine, is porphyritic, but I have nowhere else noticed this character. This trap is 

 never seen, to my knowledge, within the Huronian rocks, except in the form of fissure 

 dykes. This statement may be doubted, but I feel confident of its correctness in as far as 

 the north shore of Lake Superior is concerned, but I do not maintain that similar eruptive 

 trap may not have appeared during the Keweenian period. With the Huronian rocks, 

 granite, syenite, and different kinds of greenstones are often associated. The Animikie 

 trap beds, like the trap dykes, often alter the strata next below them. In regard to the 

 sedimentary portions, the clay slates of the Animikie are generally black, passing into 

 grey, arenaceous slate. They show a lamellar thin and thick cleavage or rather bedding, 

 and never exhibit the transverse or true slaty cleavage of the Huronian slates. The clay 

 slates of the Huronian are rarely, if ever, black in color, except in the case of an occa- 

 sional thin stratum of plumbaginous or carbonaceous schist twenty to fifty feet wide. 

 This schist may be seen on Location 14 M. east of Steel River ; it is widely different from 

 the black slates of the Animikie. The Animikie clay-stones are often micaceous, the mica 

 showing in silvery-looking scales. In the Adcinity of the silver mines, east of Whitefish 

 Lake, and again at Sawyer's Bay, Thunder Cape, and many other places, the scales are 

 small and sparcely distributed over the partings. In other places they are from one 

 quarter to half an inch in diameter and plentiful, as for instance, in the mountain-face, 

 east of Blende Lake in McTavish Township. Here the black, coarse and fine slaty 

 argillites are largely developped, underneath the Nipigon or Keweenian sandstones. In 

 all these slates the mica is fragmentai or derived from another source, while in the 

 Huronian rocks it has been crystallised in place. Another marked characteristic of the 

 Animikie black clay-slates is the occurrence through some of them of irregularly distri- 

 buted peculiar concretions, described by Sir William Logan and others. These concre- 

 tions consist of hard, argillaceous, grey masses, generally shaped like a Scotch curling 

 stone, and they are embedded in the black cleavable slates, and there concretions remain 

 solid after the enclosing dark sli#e has been denuded away. Their size varies from 

 that of an egg to a diameter of several feet, and they are, I believe, peculiar to this 

 formation, never occurring, to my knowledge, in the Huronian schists. They can be 

 seen in many places, as at Silver Mountain, Rabbit Mountain, Porcupine and Beaver 



