Geological Observations


Book Description

Excerpt from Geological Observations: On the Volcanic Islands and Parts of South America Visited During the Voyage of H. M. S. 'Beagle' Although in some respects more technical in their subjects and style than Darwin's "Journal," the books here reprinted will never lose their value and interest for the originality of the observations they contain. Many parts of them are admirably adapted for giving an insight into problems regarding the structure and changes of the earth's surface, and in fact they form a charming introduction to physical geology and physiography in their application to special domains. The books themselves cannot be obtained for many times the price of the present volume, and both the general reader, who desires to know more of Darwin's work, and the student of geology, who naturally wishes to know how a master mind reasoned on most important geological subjects, will be glad of the opportunity of possessing them in a convenient and cheap form. The three introductions, which my friend Professor Judd has kindly furnished, give critical and historical information which makes this edition of special value. 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.




Geological Observations on South America


Book Description

"[...]intrusive rocks.-Relation of cleavage and foliation to the lines of tension during metamorphosis. CHAPTER VII.-CENTRAL CHILE: -STRUCTURE OF THE CORDILLERA. Central Chile.-Basal formations of the Cordillera.-Origin of the porphyritic clay-stone conglomerate.-Andesite.-Volcanic rocks.-Section of the Cordillera by the Peuquenes or Portillo Pass.-Great gypseous formation.-Peuquenes line; thickness of strata, fossils of.-Portillo line.-Conglomerate, orthitic granite, mica-schist, volcanic rocks of.- Concluding remarks on the denudation and elevation of the Portillo line.- Section by the Cumbre, or Uspallata Pass.-Porphyries.-Gypseous strata.- Section near the Puente del Inca; fossils of.-Great subsidence.-Intrusive porphyries.-Plain of Uspallata.-Section of the Uspallata chain.- Structure and nature of the strata.-Silicified vertical trees.-Great subsidence.-Granitic rocks of axis.-Concluding remarks on the Uspallata range; origin subsequent to that of the main Cordillera; two periods of subsidence; comparison with the Portillo chain. CHAPTER VIII.-NORTHERN CHILE.-CONCLUSION. [...]."







Geological Observations on South America


Book Description

Geological Observations on South America By Charles Darwin, 1846 Although in some respects more technical in their subjects and style than Darwin's "Journal," the books here reprinted will never lose their value and interest for the originality of the observations they contain. Many parts of them are admirably adapted for giving an insight into problems regarding the structure and changes of the earth's surface, and in fact they form a charming introduction to physical geology and physiography in their application to special domains. We are delighted to publish this classic book as part of our extensive Classic Library collection. Many of the books in our collection have been out of print for decades, and therefore have not been accessible to the general public. The aim of our publishing program is to facilitate rapid access to this vast reservoir of literature, and our view is that this is a significant literary work, which deserves to be brought back into print after many decades. The contents of the vast majority of titles in the Classic Library have been scanned from the original works. To ensure a high quality product, each title has been meticulously hand curated by our staff. Our philosophy has been guided by a desire to provide the reader with a book that is as close as possible to ownership of the original work. We hope that you will enjoy this wonderful classic work, and that for you it becomes an enriching experience.