. The geology of Nova Scotia, New Brunswick, and Prince Edward Island, or, Acadian geology [microform]. Geology; Geology, Stratigraphic; Paleontology; Geology, Economic; Géologie; Géologie stratigraphique; Paléontologie; Géologie économique. ATLANTIC COAbT OF NOVA SCOTIA. 623 Igneous action may produce still farther changes. The yellow sand which results from the decay of granite is merely stained on the surface by the ferruginous colouring matter, and a very slight degree of heat is sufficient, by expelling the water of the iron rust, to convert this yellow stain into a bright red. This chang
. The geology of Nova Scotia, New Brunswick, and Prince Edward Island, or, Acadian geology [microform]. Geology; Geology, Stratigraphic; Paleontology; Geology, Economic; Géologie; Géologie stratigraphique; Paléontologie; Géologie économique. ATLANTIC COAbT OF NOVA SCOTIA. 623 Igneous action may produce still farther changes. The yellow sand which results from the decay of granite is merely stained on the surface by the ferruginous colouring matter, and a very slight degree of heat is sufficient, by expelling the water of the iron rust, to convert this yellow stain into a bright red. This change is super- ficially produced by forest fires, and might readily occur when decomposing granitic rocks have been subjected to the influence of intensely heated or molten masses, with access of air or water. Red sands and clays produced in this way, and washed into the sea, become red sandstones and shales. Such red deposits arc, however, liable to still farther change. If long washed about in the sea, the red coat is worn from the sands and added to the fine clays, so that whitish sandstones may alternate with red shales. If vegetable or animal matter is present, the changes of colour referred to in treating of the marsh mud may take place, and dark-coloured or gray beds may result, or greenish stripes and bands may appear in the mass of red deposits. Clays and sands thus deposited may be hardened into rock by pressure, by heat, or by cementing matter introduced by the per- colation of mineral waters. It will thus be perceived, that from the gi-anitic rocks it is possible to deduce a variety of yellow, brown, and gray sandstones and shales, quartzites, and slates. Many other rocks, however, beside granite have been decomposed, especially to form the more modern deposits; hence more complicated results than those above stated have been produced. Enough has, however, been said to show how much derived deposits may differ in appearance from those which have furnished their ma
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Keywords: ., boo, bookcentury1800, booksubjectgeology, booksubjectpaleontology
