Annual report . sm has produced schists difficult to describebut which are now represented by calcareous quartz-mica schists or slates, and probablywere originally, in part, quartzites or greywackes. These schists may be seen in Contactbay at the southwest end of Belmont lake, and at Roddy bay, near the mouth of theNorth river. We have not been able to find any evidence which would tend to show thatthe Keewatin greenstones are in intrusive contact with the Grenville sediments; hence,it is inferred that the greenstones formed the basement on which were deposited theGrenville sediments. Relation
Annual report . sm has produced schists difficult to describebut which are now represented by calcareous quartz-mica schists or slates, and probablywere originally, in part, quartzites or greywackes. These schists may be seen in Contactbay at the southwest end of Belmont lake, and at Roddy bay, near the mouth of theNorth river. We have not been able to find any evidence which would tend to show thatthe Keewatin greenstones are in intrusive contact with the Grenville sediments; hence,it is inferred that the greenstones formed the basement on which were deposited theGrenville sediments. Relation of Hastings series to Keewatin ami Grenville.—The Hastings conglom-erate, quartzite and slate were deposited unconformably upon the surface of the Keewatinand Grenville series. The evidence for this statement is twofold: (1) The Hastingsseries is less altered or metamorphosed than the Keewatin and Grenville, (2) Thi con-glomerate holds pebbles of some, but not all, of the older rocks exposed in this area. The. Fitf. 16 —Pebble of crystalline limestone of Orenville seriesin Hastings conglomerate. Belmont lake. water-worn pebbles of crystalline limestone, Figs. 11 and 16, which occur in the conglom-erate, are similar to the underlying limestone, proving the unconformity between thetwo series. But perhaps the most convincing evidence consists in the occurrence ofpebbles and boulders of what we have called eozoon, Figs I and 5, which cannot bemistaken for anything else. These eozoon forms, which have been describedin this report, occur in the Grenville limestone, and their presence as pebblesand boulders in the conglomerate is proof of the erosion interval between theconglomerate and crystalline limestone. The pebbles of red chert and jasper are similarto the iron formation which occurs at the northwest corner of Belmont lake, and it isprobable that they have been derived by erosion from that formation. The conglomerates at Belmont lake now rest, in so far as can be seen, whol
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectminesandmineralresou
