The Preston Gabbro And The Associated Metamorphic Gneisses New London County Connecticut

Author : Gerald Francis Loughlin
Publisher : Forgotten Books
ISBN 13 : 9781528509657
Total Pages : 184 pages
Book Rating : 4.5/5 (96 download)

DOWNLOAD NOW!

Download or read book The Gabbros and Associated Rocks at Preston, Connecticut (Classic Reprint) written by Gerald Francis Loughlin and published by Forgotten Books. This book was released on 2017-10-29 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excerpt from The Gabbros and Associated Rocks at Preston, Connecticut The area described lies within the dissected Cretaceous peneplain which extends throughout southern New England. It consists mostly of moderately Sloping glaciated hills, only a few of which rise above the 500-foot contour. Valleys or plains of considerable size com prise only a minor fraction of the area. Hills - The highest hill, Bay Mountain, in the north-central part of the area, rises more than 560 feet above sea level. Prentice Mountain, second in height, passes the 540-foot contour. Both these hills consist of gabbro, capped by patches of a basic hornfels. Most striking, however, is Lantern Hill, in the southwest quarter, which, rising 520 feet above sea level, forms a narrow ridge of almost solid quartz, with vertical walls flanked by talus. It rises 400 feet above the narrow valleys at its base, and more than 100 feet above the nearest hills. The remaining hills, which rise to a height of 500 feet or more, consist of gabbro, gneissoid granite, or quartzite. Nearly all the hills have smooth, till-covered northern and western slopes, and many Of them would be not unlike large drumlins were not their eastern and southern slopes generally rocky and in many places precipitous. Their forms are due chiefly to rock structure, and their smooth surfaces and even outlines to glaciation. Those in the north-central part of the area consist of massive gabbro which possesses little or no foliation, and are nearly circular in outline; those in the remainder of the area consist of monoclinal masses of highly foliated metamorphic sedimentary rocks, interspersed with sheets of gneissoid granite, and are elongate or elliptical, agreeing in length and slope with the strike and dip of the foliation. The gneissoid granite sheets are more resistant to erosion than the meta morphic sedimentary rocks, and the former, where of sufficient size or abundance, determine the positions of the hills. (see Pl. II.) Valley8. - The valleys may be classed as principal, major tribu taries, and minor tributaries. (see p. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.