MAR 20 1901 



No. 3. The Physiography of Acadia. By Eeginald A. Daly. 



TABLE OF CONTENTS. 



Introduction : The Unity of the Ap- 

 palachian System ; Data of 

 the Investigation .... 73 



The Uplands 75 



The Southern Plateau .... 



Structure 



Form : an Old-mountain Pla- 

 teau ; Theories of Origin . 

 Extension of the Southern Pla- 

 teau Facet 



The Cobequid Plateau .... 



The New Brunswick Highlands . 



North Mountain, Digby Neck, 



and Long Island .... 



The Bay of Fundy Trough in 



Geological Time .... 



75 



SI 



85 



Warping of the Upland Peneplain 



The Second Cycle : Development 



of the Triassic Lowlands . 



The Geological Dates of the 



Peneplains 



The Carboniferous Lowlands 

 Dissection of the Tertiary Pene- 

 plain ; Drowning and more 

 Recent History of the Ter- 

 tiary Peneplain 



Summary 



Homologies of Land-form and of 

 the Determining Structures 

 in Acadia and New England 



Bibliography 



Explanation of Plates 



PAGE 



87 



92 

 93 



96 



97 



99 

 103 



Introduction. 



The results of many independent workers in the old-mountain 

 Appalachian belt of eastern North America have shown that, as re- 

 gards axial trends, formatiorlal composition, and structure, the uplands 

 and lowlands from Georgia to Gaspe belong to one system. The unity 

 of the whole is the result of both orogenic and epeirogenic movements ; 

 the former leading to the fairly steady accumulation of Palseozoic sedi- 

 ments on a subsiding sea-floor, and to the filling with Triassic sand- 

 stones of basins produced in Nova Scotia, New England, New Jersey, 

 and Virginia during Permian warping; the latter inducing the great dis- 

 order referable to the Carboniferous " Revolution," and the simpler but 

 important block-faulting in Jura-Cretaceous time. Besides these periods 

 of wide-spread and pretty general mountain-building, other epochs of 

 more local deformation were characterized by synchronous folding in 

 limited parts of the belt. Extensive mountain-building occurred during 

 the middle Silurian folding of Acadian and of western New England 

 vol. xxxviii. — so. 3 



