RIVER TERRACES AND REVERSED DRAINAGE. 



The south-central portion of New York state, or the plateau 

 region, is furrowed by narrow north-south valleys. A study of 

 a map made by combining the United States Geological Survey 

 topographic sheets, representing the quadrangles lying between 

 the Mohawk and the Susquehanna (Chenango-Chemung)valleys, 

 draws attention to its peculiar drainage features and physiographic 

 development. The presumption of reversed drainage, suggested 

 in many instances by the map, is" often borne out by a study of 

 actual conditions in the field. 



It is not the purpose of the present paper to consider the 

 major features of a region extremely interesting and complex in 

 its physiographic history, nor to correlate the analogous surface 

 characters to be found in the numerous interrelated valleys. A 

 future paper may consider these greater problems, and the pres- 

 entation of many data gathered in field work extending over a 

 large portion of the whole area. 



These valleys of the dissected plateau region grow more 

 trenchant in character and more rugged in their topography in 

 passing from north to south. They all share in one common 

 feature : that the preglacial floors are deeply covered with drift. 

 The actual depth of filling may vary and fluctuate, but is from 

 several hundred to something less than one hundred feet deep. 

 Well borings of less than one hundred feet do not usually reach 

 bed rock (Fig. i). The locality herein considered is situated in 

 Tioga county, N.Y., along the course of the Catatonk River. 

 This stream heads in a flat, swampy divide on the valley drift,, one 

 mile east of the town of Van Etten, and, after flowing about nine 

 miles in an easterly direction to North Candor, turns abruptly 

 to the south. It maintains a practically southern direction for 

 twelve miles, and, after uniting with Owego Creek, empties into 

 the Susquehanna (Chenango) near the city of Owego. 



The main stream follows a wandering course through the 

 gravel-filled valley, never exposing rock m situ, except in one 



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