Report on the North Shore of Lake Huron

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Halaman 20 - ... certain; and the conclusive evidence given of the age of the Huron, would thus appear to settle that of the Lake Superior rocks, in the position given to them by Dr. Houghton, the late State Geologist of Michigan, as beneath the lowest known fossiliferous deposits, a position which, as will be seen by a reference to the Report of Progress I had the honor to submit to Your Excellency in 1846, appeared to me to derive some support from evidences on the Canadian side of Lake Superior itself.
Halaman 8 - ... to me, must be taken as belonging to one formation ; on the west it seems to repose on the granite which was represented in my Report on Lake Superior as running to the east of Gros Cap, north of Sault Ste. Marie ; on the east the same supporting granite was observed by Mr. Murray north of...
Halaman 20 - Superior, seem to lie in the great amount of amygdaloidai trap present among the latter, and of white quartz rock or sandstone among the former. But on the Canadian side of Lake Superior, there are some considerable areas, in which important masses of interstratified greenstone exist without amygdaloid, while white sandstones are present in others, as on the south side of Thunder Bay, though not in the same state of vitrification as those of Huron. But notwithstanding these differences, there are...
Halaman 8 - Government, in so far as it has come under my observation, presents an undulating country, rising into hills which sometimes attain the height of 400 and 700 feet above the lake. These occasionally exhibit rugged escarpments and naked rocky surfaces ; but in general, their summits are rather rounded, and their flanks, with the valleys separating one range from another, are most frequently...
Halaman 5 - Provinces of Canada, Nova Scotia, New Brunswick, and the Island of Prince Edward, and Vice Admiral of the same, &c., &c., &c.
Halaman 20 - Superior there are some considerable areas in which important masses of interstratifled greenstone exist without amygdaloid, while white sandstones are present in others, as on the south side of Thunder bay, though not in the same state of vitrification as those of Huron. But notwithstanding these differences, there are such strong points of resemblance in the interstratification of igneous rocks and the general mineralized condition of the whole as to render their positive or proximate equivalence...
Halaman 8 - The series of rocks occupying this country," says Sir William Logan, "form the connecting link between Lakes Huron and Superior to the vicinity of Shebawenahning, a distance of 120 miles, * * * [and] it appears to me, must be taken as belonging to one formation. On the west it seems to repose on the granite; * * * on the east the same supporting granite was observed by Mr. Murray. * * * The evidence afforded by the facts collected by Mr. Murray * * * is conclusive * * * that successive formations...
Halaman 8 - Government, presents an undulating country rising into hills which sometimes attain the height of from 400 to 700 feet above the lake. These occasionally exhibit rugged escarpments and naked rocky surfaces ; but, in general, their summits are rather rounded, and their flanks, with the valleys separating one range from another, are most frequently well clothed with hard and soft wood, often of large growth, and of such species as are valuable in commerce, in many places giving promise of a good arable...
Halaman 19 - Successive formations of the lowest fossiliferous group of North America were each, in one place or the other, found in exposures divested of all vegetation, resting in unconformable repose in a nearly horizontal position upon the tilted beds and undulating surface of the quartz rock and its accompanying strata, filling up valleys, overtopping mountains, and concealing every vestige of dikes and copper veins.
Halaman 19 - Huron] * * * is clear, satisfactory, and indisputably conclusive. On these islands, the Potsdam sandstone, the Trenton limestone, the Utica slates, and the Loraine shales, successive formations in the lowest fossiliferous group of North America, were each, in one place or...

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