Catalogue of the Victorian Exhibition

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1861 edition. Excerpt: ...in the physical structure of the lower Palaeozoic rocks in Victoria. The granitic intrusions do not occur along any main axes of elevation, but are dotted about over every part of the area within which the Palaeozoic rocks are found. The stratified rocks amongst which they have been intruded are invariably hardened and otherwise metamorposed for a short distance from their junction. This alteration varies in a very marked degree with the mineral character or the altering mass--thus the change produced byDiorites and Feldspar Porphyries is often very distinct from that produced by Granite. Their intrusion appears very rarely, if ever, to have exercised any influence in determining the general strike, dip, and contortions of the Palaeozoic rocks: --these invariably retain their general meridional direction, which is certainly remarkable, considering that the main water-shed or axis of elevation runs from east to west, and consequently nearly at right angles to the strike of all the older rocks. It is difficult, under these circumstances, to understand what influence can have determined this feature in the physical geography of Victoria. That no great alteration, or even modification of the water-shed, has taken place since the earliest tertiary periods is well proved by circumstances connected with the physical geology of the formations of that period, as exhibited on either side of the dividing range. The quartz veins occur throughout the lower Palaeozoic rocks, from the size of a thread to many feet in thickness. They have mostly a nearly true meridional direction, and are inclined either east or west, at angles varying from horizontal to vertical; occasionally they occur between the planes of the strata--more frequently in those of..