204 



CAPE COD GEOLOGY 



CHAPTER III 



GEOLOGY OF NO MANS LAND 

 By J. B. Woodworth 



LOCATION 



No Mans Land is a small island of glacial drift that lies nearly due south 

 of Gay Head light and about 4 miles south by west of Squibnocket Point, the 

 southernmost part of Gay Head. The island rises above the submerged surface 

 of a broad ridge that extends southward from Gay Head, as if it were a structural 

 continuation of the island of Marthas Vineyard. The submarine contours of 

 this ridge are shown on the charts of the U. S. Coast and Geodetic Survey 1 (See 

 Plate 26). About halfway between the island and Gay Head two large rocks, 

 known as Lone Rock and Old Man Rock, lie on shoals and are visible in the 

 water from small vessels plying between Menemsha and the island. 



GEOGRAPHIC FEATURES 



No Mans Land has a maximum length of 1.6 miles from east to west and a 

 maximum width of 1 mile from north to south. Owing to the existence of a 

 small sandspit on its north coast and the incurving of its south coast toward 

 its northwest point its average width is about half a mile. Its present area is 

 somewhat less than 1 square mile. At a few places its surface rises to a height 

 of 100 feet, but most of it lies below this level. The surface is decidedly undu- 

 lating, consisting of knobs and hollows simulating the morainal deposits of many 

 typical frontal moraines. The coast of the island on its east and south sides 

 consists of steep cliffs of boulder clay, other clay, and sand, which are being 

 rapidly worn away by the sea. The small sandspit that runs out near the middle 

 of the island on its north side encloses a little lagoon on its eastern flank. This 

 sandspit appears to have been in nearly its present position in 1602, at the time 

 of Gosnold's landing, but according to Brereton's account, the lagoon on the east 

 side of the island was then larger, probably extending eastward behind a flying 

 beach, which has been driven backward and inward with the retreat of the 

 cliffs at the east end of the island. An old sea cliff, largely grassed over, may 

 be seen on the north coast west of the sandspit. 



i See chart of Marthas Vineyard, No. 112, 1914, 1/80 ; 000; also chart 1107, showing Southwest Shoal 

 and neighboring waters. 



