. Annual report . everal places on theshore of Black lake, and on the islands in the lake where it can be observed very dis-tinctly. Here the strike of these interbanded rocks is a little west of north and theirdip is almost 90r to the west. The remnants of several folds of interbanded rocks,strikingly similar to those on the islands in Black lake, occur on the east side oflleiron lake and appear to be overlain by the tiat lying banded slate of the Cobaltseries. It appears from their relation to the Cobalt series and from their disturbedcondition that these folded and steeply dipping fragmenta
. Annual report . everal places on theshore of Black lake, and on the islands in the lake where it can be observed very dis-tinctly. Here the strike of these interbanded rocks is a little west of north and theirdip is almost 90r to the west. The remnants of several folds of interbanded rocks,strikingly similar to those on the islands in Black lake, occur on the east side oflleiron lake and appear to be overlain by the tiat lying banded slate of the Cobaltseries. It appears from their relation to the Cobalt series and from their disturbedcondition that these folded and steeply dipping fragmental rocks belong to the Temis-loming series. In the vicinity of Black and Spider lakes a grey-colored, cherty-looking porphyriticrock is exposed in several places. The phenocrysts are usually feldspar and disturbances have crushed and brecciated the porphyry in places to such an. stent that it resembles a fragmental rock. The Pleistocene deposits effectually conceal the underlying rocks in several parts. Fig. !»0.—Folded sedimentary rucks, east side of Herron lake. Leonard township. of the area, but in other places a thin sheet of boulder till forms the superficialmaterial. Esker-like ridges of sand and gravel occur in several places, and sanddeposits cover stretches of considerable size. Slight stratification was observed in thesand about half a mile southwest of Fournier lake. Character of the Veins The silver-bearing veins occur in the Nipissing diabase, although similar veinshave been located in the agglomerate and conglomerate. The veins occupy distinctvertical fissures that have a general strike of north thirty to forty degrees east (mag-netic). Some east and west fractures occur in the diabase, but these are generallymere cracks. Numerous veins occur on many of the properties, but the majority of them willaverage only a few inches in width. Large veins, four to eight feet wide in placesand extending across two or three adjoining claims, are a rather marked
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectminesandmineralresou
