OUTLINE OF THE GEOGRAPHY AND GEOLOGY 

 OF THE REGION 



By J. B. Wood worth 



INTRODUCTION 



The first part of this report presents a general view of the district surveyed 

 and summarizes the palaeontologic data ; the second part describes in detail each 

 particular area considered. Although this method of treatment involves some 

 repetition, it has been employed in order to adapt the matter to the use of the 

 general reader on the one hand, and of the reader who may be interested in a 

 particular area or island on the other. 



The field work on which the report is primarily based was done in the sum- 

 mers of 1914 and 1915. Assistance in the field was received from Mr. Gilbert 

 Hart, who deserves particular mention for his work on the Elizabeth Islands, 

 west of Naushon. Many observations that have been utilized were made by me 

 during visits to Cape Cod and the islands, either in connection with the work of 

 the United States Geological Survey or as instructor in geology at Harvard Uni- 

 versity. 



Dr. Wigglesworth studied the geology of Marthas Vineyard at his own 

 expense under my direction, and his original manuscript, of which the accompany- 

 ing account of the geology of that island is an abstract, was filed in the archives 

 of Harvard University in part fulfillment of the requirements for a doctorate. 



Thanks are due to Dr. T. W. Vaughan and to Dr. W. C. Alden for advice 

 and personal consultation in the field concerning some mooted points in the 

 Pleistocene history of the district, and especially to Dr. W. H. Dall for the iden- 

 tification of the marine fossils. 



TOPOGRAPHY 



Cape Cod is a peninsula composed of gravel, sand, and clay, which extends 

 from southeastern Massachusetts into the sea in the form of a bent arm that 

 encloses Cape Cod Bay. South of Cape Cod there is a group of islands, some- 

 times called "the New England Islands," which includes Nantucket, Marthas 

 Vineyard, No Mans Land, Block Island, and the Elizabeth Islands. These islands 

 are separated from the mainland and from Cape Cod by navigable sounds. Al- 



