CAPE COD GEOLOGY 



131 



KETTLES 

 Kettles are not common in the outwash plain; indeed, with the exception 

 of two conspicuous examples, they may be said to be absent. One of these is 

 about a mile and a half due south of the head of Lagoon Pond, the other is about 

 two miles west of the first. Both are large and are shown on the topographic 

 map. One is near the house of the superintendent of the Massachusetts State 

 Game Reservation and is occupied by a small pond. It is the larger and deeper 

 of the two and is of very irregular outline. The other is fairly regular in outline 

 but is little more than a broad, shallow depression. These kettles were doubt- 

 less not formed by ice blocks, for they lie farther south than the probable 



W 



Fig. 9. — a. Generalized profile of a channel or crease, showing the relative 

 steepness of the east and west bank. b. Profile of Watcha Pond channel, 

 showing extreme difference in form of opposite slopes. 



southern limit of the ice; though possibly the ice of early Wisconsin time may 

 have extended southward beyond that supposed limit, and all traces of it may 

 have been obliterated by the material laid down on the outwash plain when the 

 ice front occupied the position marked by the contact slope south of Lagoon 

 Pond. Or, more probably, they were once parts of the numerous channels 

 that were cut off from the present channel by local deposits of outwash ma- 

 terial. The last suggestion is supported by the facts that the large kettle on 

 the State Game Reservation is not far from the head of the deep Oyster Pond 

 Channel and that the other kettle is near the head of the former drainageway 

 to the head of Edgartown Great Pond. 



