[Annals N. Y. Acad. Sci., Vol. XIII, No. 3, pp. t,6i-^^o, Jan. 12, 1901.] 



THE SECTION AT SCHOHARIE, N. Y. 

 John J. Stevenson 



(Read October i6, 1899) 



CONTENTS 



PAGE 



Introduction 361 



The Hudson ; its relation to the Medina Formation at southern localities 362 



The Niagara 363 



The Onondaga ; represented by the Waterlime ; and its relation to the Niagara 



and to the Helderberg series 364 



The Helderberg ; its subdivisions 366 



The Oriskany ; its relation to the Helderberg 374 



The Corniferous [Onondaga] ; and its subdivisions 375 



The Hamilton 377 



List of localities for collectors 377 



Appendix : Glacial action in the Schoharie Valley, by Archibald E. Stevenson 378 



INTRODUCTION 



The Schoharie River rises on the easterly side of the Catskill 

 mountains, flows westwardly across the rugged area, then turns 

 northwardly and finally enters the Mohawk river near Amster- 

 dam, about one hundred miles from its source. It cuts the 

 Helderberg escarpment at little more than a mile below the vil- 

 lage of Schoharie in the county of the same name. 



The Helderbergs are practically the northwestern border of 

 the mountainous synclinal area known as the Catskills, the 

 southeasterly border being the Shawangunk mountains. The 

 section shown in the wall, as seen for many miles along the 

 Delaware and Hudson railway, extends from the Hudson to the 

 Hamilton, while the Chemung is reached at from one to four 

 miles from the escaipment's edge. The succession is shown in 

 such detail at many places that this Helderberg scarp from near 

 Annals N. Y. Acad. Sci,, XIII, Jan. I2, 1901 — 24. 



(361) 



