Description of a Series of Elementary Geological Models; Illustrating the Nature of Stratification With Notes on the Construction of Large Geological Models - Softcover

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1875. Excerpt: ... Association, an office has been established in connection with the Museum of Economic Geology, for the purpose of preserving such records. Where great complexity of structure exists, it is only by means of models that the various relations of stratified rocks and mineral veins can be adequately represented, and the examples here given afford some views of appearances which, if not examined carefully, may lead to very deceptive inferences. Model VI. INTERSECTION OF MINERAL VEINS. The preceding models by their forms exhibit the geometrical relations of the several rocks as they would appear on planes, either coinciding with, or at right angles to the strata; the present example, No. VI., represents similar strata under precisely similar conditions as regards dislocation, but with the surface denuded, and with the appearance of mineral veins and rocks at their respective outcrops at the surface. In this example the strata are horizontal, and the solution of the various features is therefore comparatively easy; but 400 PEET. when the strata are inclined, the complexity is much increased. In the former series of twelve models I attempted to explain some of the more complicated problems of geology so far as practical mining is concerned; and by dividing Model VI. into two parts, I have been able to present some interesting surface phenomena, with two subterranean representations--one being horizontal, and the other inclined. On the surface will be at once recognised the upper thin seam of coal, and the lower or thick seam. In this model mineral veins are represented, one by a white, the other by a brown line. The base of the model represents a ground-plan of the horizontal direction of the veins and their intersection, the white vein being carried off its point...