EARLY PALEOZOIC PHYSIOGRAPHY OF THE 

 SOUTHERN ADIRONDACKS 



BY WILLIAM J. MILLER 

 ■ INTRODUCTION 



For many years the problem of the early Paleozoic physi- 

 ography of the Adirondack region has been an important one to 

 all interested in the geological history of northern New York. 

 Observations made during the past ten or fifteen years have thrown 

 much light upon this problem, especially significant being the 

 work of Gushing, Kemp, Ruedemann, and Ulrich. For some 

 years the wTiter also has been studying the geology of the 

 southern Adirondacks, the five quadrangles which he has map- 

 ped in detail all having important bearings upon the subject. It 

 is the purpose of this paper to bring together old and new ob- 

 servations in an attempt to reconstruct the major physiographic 

 features of the southern Adirondack region during the Gambric 

 and Ordovicic periods. The Black river, Mohawk and Gham- 

 plain valleys will be discussed only in so far as facts from those 

 regions have a direct bearing upon the problem. Since the 

 Paleozoic rock outliers in the southeastern Adirondacks are 

 particularly significant in this connection, they will be duly 

 emphasized. 



Some of the principal questions discussed are the following: 



1 What was the character of the surface of the Precambric 

 rock upon which the early Paleozoic sea encroached? 



2 Were the early Paleozoic sediments deposited in embay- 

 ments of the sea extending into the Precambric rock area or did 

 they form a more general mantle over the Precambric rocks? 



3 Was the southern Adirondack region ever completely sub- 

 merged during the Paleozoic era and, if so, when? 



4 Where were the principal land areas located during the 

 Gambric and Ordovicic periods? 



5 Does the present northeast-southwest main axis of eleva- 

 tion through the Adirondacks also have an early Paleozoic 

 significance? 



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