CAPE COD GEOLOGY 



185 



eastern area where the Montauk may be exposed. In Edgartown village a man 

 who has dug many wells says that a bed of tough hard pan containing pebbles 

 lies beneath several feet of loose gravel. South of the Edgartown- Vineyard 

 Haven road, a little more than a mile west of Edgartown, there is an area of clayey 

 till, used for road material, which is distinctly different from any Wisconsin 

 material. Unfortunately, its relations to the other deposits cannot be deter- 

 mined. Its striking characteristic is its reddish color. In its nature it is more 

 like Montauk than Wisconsin. This exposure is in what the natives call "the 

 red ground." This red ground is elsewhere poorly exposed, but traces of it 

 found in the northeastern area extend somewhat north of west from this locality 

 along the northern edge of the great plain, especially near the superintendent's 

 house on the State game reservation. The same material is found just north 

 of the State road about a quarter of a mile west of the head of Chappaquonsett 

 Pond, in the western area. 



. The Montauk till is exposed at many places in the western area. The best 

 exposures are in the cliffs, and those at Squibnocket are the most noteworthy. 

 (See fig. 17) . Here the cliff is made up largely of this member and shows zones 

 of different color. The upper part here is brownish, a color quite different from 

 that of the chocolate-colored till below it. Below the chocolate-colored till there 

 is a grayish till. Some of the coloration here is undoubtedly due to weather- 

 ing, but some is original, for near its base the till is at some places composed of 

 Cretaceous clay and at others of the Gardiners clay. At the west end of the 

 Squibnocket cliff the Wisconsin overlies the Montauk. Elsewhere in the section 

 it is hard to make out any Wisconsin covering. It may exist here, but it is 

 probably similar to the Montauk. 



In about two-thirds of the section at Squibnocket cliff the Montauk till 

 overlies the Herod gravel, below which, for a short distance, the Jacob sand and 

 Gardiners clay are seen. The typical erosion forms of the Montauk are seen 

 here better than anywhere else, and on this account this shore closely resembles 

 the south shore of Block Island. The formation is eroded into sharp gullies, 

 intervening pinnacles, and minaret-like forms, such as are seen in badland 

 topography. (See Plate 25, fig. 1.) Here and there large boulders are imbedded 

 in the till, and the whole shore here is a bouldery beach, which owes its character 

 to these erratics from the Montauk. 



Other exposures of the Montauk till are seen in the Stonewall Beach cliff, 

 at the west end of Nashaquitsa cliffs, and on Gay Head. The Montauk is 

 probably rather widely distributed through the town of Gay Head and lies 



