CONTENTS 



Pakt I. Outline of the Geography and Geology op the Region, by J. B. Woodworth 



page 



Introduction 3 



Topography 3 



General geology 9 



Pre-Cretaceous basement . 9 



Cretaceous system ............ 13 



Tertiary system 15 



Eocene and Oligocene series 15 



Miocene series 17 



Earlier investigations 17 



Character of the deposits . 19 



Gastroliths in the greensand at Gay Head .19 



Greensand at Duxbury and Marshfield 20 



Origin of the greensand 21 



Chemical analyses of the greensand 23 



Fossils from the greensand at Gay Head and Nashaquitsa . . . 24 



Fossils from the greensand at Marshfield and Duxbury ... 27 



Miocene fossils from other deposits . . . . . . . 27 



Phosphatic nodules in the greensand ....... 28 



Eastward extension of the Miocene deposits 29 



Pliocene series 30 



Quaternary system 32 



Pleistocene series 32 



Early investigations 32 



Classification of the Pleistocene deposits adopted in this report . . 35 



Aquinnah conglomerate (osseous conglomerate) 36 



First stage of glaciation 38 



Dukes boulder bed (first glacial substage) 39 



Weyquosque formation (glacial) ....... 40 



Sankaty sand (marine) 41 



Mannetto formation (glacial) 45 



Folding at Gay Head 45 



Post-Manetto interglacial stage ........ 46 



Jameco stage of glaciation 47 



Jameco formation .47 



Ferruginous boulder bed 47 



Coarse gravel of Jameco type . 47 



Moshup till member ........ 48 



Gardiners interglacial stage ......... 48 



Gardiners clay 48 



Distribution and character 48 



Fossils and origin 49 



Jacob transitional stage ......... 51 



Jacob sand . 51 



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