BBPORT OF THE DIRECTOR AND STATE GEOLOGIST 



r95 



The large swamp east of Alexandria Bay is a tangle of schists 

 and granite-gneiss so confused that their separation is almost 

 impossible, and the mapping must be taken as merely a rough 

 approximation to accuracy. 



( 'ontinuing southeasterly, the schists again appear in the neigh 

 borhood of Redwood, and extend in a broad belt northeastward 

 to Black lake. This is one of the most interesting of all of the 

 belts of the metamorphosed sedimentary series in this part of the 

 state, on, account of the variety of rocks it contains. Crystalline 

 limestone, coarse grained white and graphitic, is abundant and 

 serves to correlate the formation with the extensive limestone 

 belts farther south. This rock appears in small quantity about a 

 mile north of Redwood, and is widespread to the east of Butter- 

 field lake. Typical vitreous quartzite is another important feat- 

 ure of the belt, forming a high steep ridge south of Butterfield 

 lake, along the road from Redwood to Rossie. The rock is iden- 

 tical with (hat of Wells island, and thus serves to connect the 

 latter, together with its associated schists, with the crystalline 

 limestone formation. 



Across the road from the quartzite, another high ridge occurs, 

 made up of hornblende, mica, and pyroxene schists and very 

 impure limestones. The pyroxene schists are so closely similar 

 to those of the schist ridges above described that, as already 

 stated, there can be no doubt that the latter also are to be re- 

 garded as belonging to the limestone formation. This correlation 

 is rendered even more sure by the fact that these rocks near 

 Butterfield lake bear the same relation to the granite-gneisses 

 that the other schists do. This is clearly shown by dikes of the 

 pink granite and granite gneiss cutting the schists near the quart- 

 zite ridge, and reproducing all of the structural features shown 

 in the localities before described. 



This locality is of much interest, as it affords an excellent 

 showing of the crystalline rocks that are regarded beyond ques- 

 tion as of sedimentary origin. Quartzite, dark hornblende schist, 

 mica schist, pyroxene schist, and pyroxene and mica gneisses 

 with impure limestones succeed each other rapidly and abruptly 



