GLACIAL GEOLOGY OF THE SARATOGA QUADRANGLE 37 



may have been further extended by deposits made by the streams 

 and derived from sources beyond (north of) the moraine. At the 

 present time there is an approximately dead level aggradation plain 

 extending for nearly 3 miles south of the morainic area. This level 

 plain is continuous with a valley plain bordering Kayaderosseras 

 creek but gradually falling in level correspondingly with the fall in 

 the bed of the creek. North of North Greenfield, where there is a 

 fall of more than 20 feet a mile, the valley plain is comparatively 

 narrow, but south of the same place the plain expands to an excep- 

 tional width. At Kings it is approximately 1 mile in width and the 

 broad flat has a north-south extension of about 2 miles. The mate- 

 rials of the flat lands consist predominantly of sand with a consid- 

 erable amount of vegetable debris at the surface. Beyond this area, 

 bordering the creek in its further course, deposits of stream origin 

 occur. In places they are somewhat marked in development, ex- 

 tending considerable distances back from the creek, and rising to a 

 level of perhaps 20 feet above the creek. This statement applies to 

 deposits as they occur along the creek only as far as the village of 

 Ballston Spa. 



It is not to be supposed that these deposits have been laid down 

 by the present drainage streams since the close of the glacial period. 

 At South Corinth station the plain extends without interruption 

 across the divide between the two creeks. The great mass of de- 

 posits at Kings is within a few miles of the sources of the creek 

 traversing its surface. Farther south deposits occur, as just noted, 

 relatively high above the present flood level of the creek. The de- 

 posits, therefore, are attributable to late glacial floods. 



3 Eroded till. The slopes of the valley of Kayaderosseras 

 creek show water-swept features. The till has been eroded and in 

 places, especially at Rock City Falls, entirely swept away, leaving 

 areas of bare rock. The eroded surfaces are marked by loose 

 boulders, which occur in greater numbers than in the uplands. In 

 places, the effect of powerful currents in shaping the present slopes 

 is evident. Thus west of Rock City Falls on the south side of the 

 stream, there is a steep bluff of till where the currents impinged 

 against the sides of two drumlins having axes lying in the same 

 line. On the opposite side of the creek at the same place the slope 

 is gentle and the somewhat evened surface shows water-worn fea- 

 tures. North of West Milton, embraced by a curve in the stream, 

 is a plateaulike area of eroded till, delimited sharply on its east side 

 from a group of sand hills of distinctive kame features. It is evident 



