430 CHARLES EMERSON PEET 



DRIFT IN THE HUDSON VALLEY SOUTH OF THE HIGHLANDS AND NORTH 

 OF LONG ISLAND AND STATEN ISLAND. 



The deposits of drift of special significance in this area occur 

 north of Ossining (Sing Sing), where the valley begins to broaden 

 out into Haverstraw Bay. Most of the deposits south of here are 

 covered by the "Surficial Geological Maps" of the New York 

 City Folio, and are mentioned in its text. The deposits of drift of 

 special significance in this part of the valley belong to the two classes 

 of high-level terraces mentioned above (p. 228). The features of 

 Class I, similar to those found in the Highlands, are found (i) in a 

 terrace at 120-100 feet A. T. from north of Sing Sing to south of 

 Croton River mouth; (2) at Jones Point; and (3) features of similar 

 import occur at Roye Hook near State Camp, Peekskill. These 

 features are shown in Fig. 9, the first between Nos. 20 and 21, the 

 second at No. 19, and the third at No. 29. To which class some of 

 the features of a high-level terrace from Peekskill toward Osca- 

 wanna belong is a question. (See Fig. 9, Nos. 23, 24, 25). The 

 features of Class 2, similar to those prevailing in the Appalachian 

 Valley part of the Hudson, occur at Croton Point and Croton Land- 

 ing on the east side of the river, and from Haverstraw to north 

 Haverstraw on the west side. (Fig. 9, Nos. 21, 22, and 15 and 17.) 



Haverstraw. — The deposits at Haverstraw of interest in connec- 

 tion with this paper are of four types: (i) the narrow moraine at 

 the foot of the Pahsade Ridge; (2) a gravel plateau with undulatory 

 topography and delta-like structure at an elevation of less than 120 

 feet A. T., which is underlain by laminated brick clays, yellow in 

 color above, and blue below; (3) low-level gravel and clay. 



I. The moraine: The position of the ice-edge as it rested near 

 the northern base of the Trap Ridge, which farther south makes 

 the Palisades of the Hudson, is marked in the southern part of Hav- 

 erstraw by a narrow moraine with a west-by-north and east-by-south 

 trend, parallel approximately to the trend of the Trap Ridge. Where 

 well-defined this moraine has a width of one-fourth to one-half of a 

 mile. It has been traced for a distance of about two miles, from a 

 point about one mile southeast of Thiell's Station to within some- 

 thing less than three-fourths of a mile northwest of Short Clove. It 

 extends farther east in the form of a ridge, but with less definition. 



