XXXVIII. Notes on the Earthquake district of the county of Perth

Abstract

The district of Scotland, which has been long subject to considerable earthquake shocks, is bounded N.W. and S.E. by two great depressions, which range diagonally across the country from sea to sea, and enclose a peculiar suite of rock formations. Along an irregular medial line, which has often been denominated an axis, granites, porphyries, and quartzites, are developed in independent masses. Between, and on either side of these, gneiss and mica slate occur, flanking the erupted groups, outside of which is placed an assemblage of slates of varying mineral structure, amid which mica slate and roofing slate figure largely—beds of precisely similar structure occurring again and again on lines transverse to the range, or in the line of general dip, apparently from the occurrence of great folds in the strata, placed in a synclinal position. Discontinuous beds of limestone are found among these slates, in all situations, from the outer edge, as at Kilcreggan, to the heart of the tract, as at Lochearn-head, Killin, Lismore, c and among them, as among the slates, it was recommended that a diligent search be made for fossils; the late extraordinary discoveries in Canada rendering it highly probable that here, as there, the horizon of life may be carried down almost to the central granite. The author then showed that, in regard to the Grampians, This 250-word extract was created in the absence of an abstract