EXPOSURES OF THE AJIBIK QDAETZITE. 283 



South of the Negauuee fonuatioii, hi sec. 35, T. 47 N., R. 26 W., there 

 appears a quartzhe, placed witli the Ajibik quartzite, which extends west- 

 ward ahnost conthuiously to sec. 31. The belt here swings to the north, 

 northeast, north, and finally west again, about an anticline in the Archean, 

 and then extends in a general westerly course to sec. 20, T, 47 N., R. 28 W.; 

 thence northwest to near Humboldt, in sec. 12, T. 47 N., R. 29 W. Expo- 

 sures of quartzite reappear at the base of the Lower Marquette series on 

 both sides of the Rei)ublic and Western tongues. It is doubtful whether this 

 western part of the quartzite is really the time equivalent of the remainder of 

 the Ajibik quartzite. Throughout the district it is natural, almost inevitable, 

 that at the base of the sedimentary series there should have been deposited 

 a conglomeratic quartzite. It is therefore not impossible— indeed, it is 

 probable— that the westward part of this belt of quartzite belongs, in age, 

 Avith the lower part of the Siarao slate as developed to the east, rather 

 than with the Ajibik quartzite. However, as this quartzite constitutes a 

 continuous lithological formation, and as there is no basis upon which to 

 make the equation, and as above it there occur the representatives of the 

 Siamo slate, at least as far west as sec. 28, T. 47 N., R. 27 W., the whole 

 formation is here considered. 



On account of the resistant character of the quartzite, at various places 

 it becomes one of the chief topographic features of the district. South of 

 the southeast arm of Goose Lake the bold quartzite exposures rise steeply 

 from the lake, and from the sand plain to the east and south. The series 

 of ledo-es composing the quartzite belt are almost continuous to the west- 

 ward, everywhere rising abruptly from the valley to the south, and in sees. 

 27, 28, and 29, T. 47 N., R. 26 W., the quartzite constitutes the Ajibik Hills, 

 a bold east-and-west ridge, with precipitous, south-facing exposures. This 

 ridge rises about 200 feet from the valley of Ajibik Creek. On the north 

 side the ridge falls away less steeply to the exposures of the Siamo slate. 

 While this ridge has the general features above given, in a smaller way 

 it is exceedingly rough, a north-and-south traverse ascending precipitous 

 bluffs, to almost immediately descend into a steep ravine, the other side 

 of which must be climbed but to repeat the performance As has been 



