PREFACE 



TO THE FIRST EDITION 



This book is addressed especially to advanced undergraduates in geol- 

 ogy. I doubt that it could have been written on a more elementary level 

 and still presume to use the common terminology of the numerous source 

 publications and the language of the professional geologists. In fact, some 

 instructors may consider the book too advanced for undergraduates. I 

 have endeavored, however, to take such measures as will make it under- 

 standable to the student who has had basic courses in mineralogy, 

 lithology, and structural geology. It will be well if he has had a course 

 in stratigraphy in which correlation problems have been discussed and 

 in which some attention has been given to the sedimentary environments 

 and sources. 



The reader's attention is lost most frequently by the use of unfamiliar 

 formational, fossil, and geographic names. Generally I have not used 



formational names in the text but, instead, have referred to the dep< 

 by period, epoch, or stage, and have listed the formational names in 

 charts. This has the advantage of easing the reading of the text and still 

 making the student aware of the many formations in the various parts ot 

 the country. At the same time it sets the stage for meaningful stratigraphic 

 studies in other courses. 



I have discussed stratigraphic correlations only where necessary, anil 

 have relied on the latest authoritative correlations in the literati.: 

 graphic names have been treated with care, and I believe all that have 

 been mentioned are on accompanying maps and figures, or on other well- 

 known maps which are referred to as the occasion arises. Where petro- 

 graphic research has been referred to, I have attempted to discuss it in 

 such terms that the student with a knowledge of the common roik names 

 will understand. 



Several professors who teach structural geology have expressed to me 

 the need for a text that treats structural geology from a regional point of 

 view, hut I doubt it the present volume is what they want, or that it can 

 be used as a substitute for the standard textbooks on principles. It may 

 be that in those departments where structural geology is taught as a senior 

 course, the hook could be used, and principles could he developed col- 



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