GLACIAL GEOLOGY OF THE SARATOGA QUADRANGLE 1 9 



The Milton plain is an area of well-defined physiographic feat- 

 ures. In the greater portion of its expanse its surface approxi- 

 mates a dead level. The road running nearly due north from the 

 village of Ballston Spa traverses 4 miles of sandy and in part bar- 

 ren and desertlike lands. The east-west road from Milton Center 

 crosses the same tract, measuring a distance of about 3 miles. 

 This area is practically destitute of streams, the rainfall sinking 

 into the porous soils. The plain has a clear relief of 80 feet above 

 the Saratoga plain. The transition from the upper to the lower 

 plain is a slope of irregular and broken surface but in its larger 

 outlines, as shown by the map contours, having marked lobate 

 features. Along these slopes there is a series of springs whose 

 waters are obviously derived from the sands of the plain and repre- 

 sent its drainage. They are of considerable volume and constitute 

 the source of public water supply for the village of Ballston Spa. 



The southern extension of the Milton plain is crossed by Kay- 

 aderosseras creek which, as stated above, has cut through the sands 

 and, in its lower course, through the underlying till into bedrock. 

 The 400 foot level of the plain is shown in a portion of the area 

 beyond the creek but farther to the south the elevation of the plain 

 becomes reduced. Its limit to the south is about a mile beyond the 

 edge of the sheet where it forms two lobes which gradually thin 

 out at their margins (see map of Schenectady sheet accompanying 

 New York State Museum Bulletin 154). The two lobes were, how- 

 ever, originally one, the division having been made by a late glacial 

 water course, the channel of which is now occupied by Mourning kill 

 which flows northward to the Kayaderosseras about a mile east of 

 Ballston Spa. 



The Mii'lton plain is clearly a delta built into Lake Albany by a 

 stream coming from the north and which in its lower course fol- 

 lowed the valley now occupied by Kayaderosseras creek. It will 

 be shown farther on in this report that this stream was a portion 

 of the Hudson river which in the time of flooded waters was di- 

 verted southward from the present Hudson valley at Corinth. 



In addition to its level surface and its lobed margin, evidence 

 that the Milton plain is a delta in origin is afforded by the arrange- 

 ment of its materials. In a sand pit near the northern limits of the 

 village of Ballston Spa an exposure of about 35 feet of the upper 

 portion of the formation is shown. The sands are stratified, mainly 

 in inclined layers, representing, apparently, the fore set beds of the 

 delta. The layers vary in respect to size and sharpness of grain 

 of the sands, indicating fluctuating currents. 



