. Acadian geology [microform] : the geological structure, organic remains and mineral resources of Nova Scotia, New Brunswick and Prince Edward Island. Geology; Paleontology; Geology; Geology; Geologie; Paléontologie; Géologie; Géologie. w 622 THE LOWER SILUniAN PEUIOD. St Lawrence, and the movemeuts of its beds may have begun in con- nexion with the disturbances which Logan and others have shown to have occurred at the close of the Lower Silurian period; but the intrusive granite appears to be continuous with that of Devonian age described in a previous chapter. Whatever view may be taken of
. Acadian geology [microform] : the geological structure, organic remains and mineral resources of Nova Scotia, New Brunswick and Prince Edward Island. Geology; Paleontology; Geology; Geology; Geologie; Paléontologie; Géologie; Géologie. w 622 THE LOWER SILUniAN PEUIOD. St Lawrence, and the movemeuts of its beds may have begun in con- nexion with the disturbances which Logan and others have shown to have occurred at the close of the Lower Silurian period; but the intrusive granite appears to be continuous with that of Devonian age described in a previous chapter. Whatever view may be taken of the age of the granitic rocks of this group, it is certain that they are strictly hypogene rocks, that is, that they belong to the deep-seated foci of subterranean heat, and are not superficial products of volcanic action. They are sub- stances such as we might expect to find, could we penetrate miles below the surface, beneath modern volcanoes. They were therefore probably at one time buried deeply, and have been brought up by movements of dislocation, and by the removal of their superficial portions by aqueous agents. They have without doubt furnished much of the material tiiat has been employed in building up the more recent formations of the country. This leads to the question. Can we discover in the subsequent rock formations evidences of such an origin, and can the changes which these derived materials have undergone be satisfactorily ex- plained ? This subject, the genealogy of rocks as it may be termed, is of some interest, and I may glance at it in its bearing on the geology of Nova Scotia. The granite of Nova Scotia and its associated gneiss and mica- slates are among the oldest rocks found in the province, and we may therefore take them and their derived rocks for illustrations. The products of the decomposition of granite are quartz sand, scales of mica, and fine clay which results from the decomposition of felspar. Such materials, when washed down and deposited
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Keywords: ., boo, bookcentury1800, booksubjectgeology, booksubjectpaleontology
