Annual report . -ton and Frontenac, and lies immediately to the east of the Madoc area. The outlineof the map was determined solely by the remarkable form of the belts of Hastings con-glomerate which occupy the central parts of the area. One of these belts is abouttwenty-two miles long and a mile wide at the widest part. The conglomerate has beenreferred to by the early workers, including Logan, .Murray and Vennor, but no attempthas hitherto been made to connect up the isolated outcrops, a few of which were brieflyalluded to by these writers. The stratigraphic significance of the conglomerate
Annual report . -ton and Frontenac, and lies immediately to the east of the Madoc area. The outlineof the map was determined solely by the remarkable form of the belts of Hastings con-glomerate which occupy the central parts of the area. One of these belts is abouttwenty-two miles long and a mile wide at the widest part. The conglomerate has beenreferred to by the early workers, including Logan, .Murray and Vennor, but no attempthas hitherto been made to connect up the isolated outcrops, a few of which were brieflyalluded to by these writers. The stratigraphic significance of the conglomerate was notappreciated. References to the literature are given on preceding pages. The Keewatin series consists of green schists which, at the northeast part of themap, pass into typical pillow lavas, Fig. 20, thus proving the igneous origin of theseschists. The order of deposition of the Grenville sediments, which rest on ^nd areyounger than the Keewatin lavas, has been determined in this area as well as at Belmont. Fig. 19.—Channel of Skootamatta ri\er through crystalline limestone at Actinolite. lake. The basal members of these sediments consist of quartzite and greywacke,together with at times rusty schists and jaspilyte; these rocks are succeeded by lime-stones. The Keewatin and Grenville series were intruded by Laurentian granite andsyenite, and, after a prolonged period of erosion, the Hastings conglomerate was laiddown on the three older series of rocks, namely, Keewatin, Grenville and Laurentian. It will be noted that our map shows that much of the area consists of Laurentiangranites and gneisses, but it is possible that some of the rocks mapped as Laurentianmay be intrusive into the Hastings conglomerate. When a granite has not been foundin contact with the Hastings conglomerate it is difficult to determine its stratigraphicposition. Intruding the Keewatin, Grenville, Laurentian and Hastings are granite, pegmatite,basalt, diabase, and other rocks. The description of the
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectminesandmineralresou
