1974. "Introduction", Geology of the Arisaig Area, Antigonish County, Nova Scotia, A. J. Boucot, J. F. Dewey, D. L. Dineley, R. Fletcher, W. K. Fyson, J. G. Griffin, C. F. Hickox, W. S. McKerrow, A. M. Ziegler
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Purpose and Scope of the Investigation
The Arisaig area (Fig. 1; Pl. 1) has been selected for detailed study because it provides the most continuous and best exposed sections of marine Silurian and early Lower Devonian rocks in the Appalachian Mountain system. The earliest fossiliferous rocks present are lower Llandovery in age, and it is probable that the whole of the Silurian is represented in the 4,000 ft of beds that make up the Arisaig Group; but the underlying Bears Brook Volcanic Group has no known fossils, and the Silurian rocks are faulted against the Ordovician Browns Mountain Group. It is not clear, therefore, how large a stratigraphic break, if any, is present at the base of the Arisaig Group. The marine Silurian succession passes without a break up into marine Lower Devonian; the system junction comes near the top of the Stonehouse Formation. The basal marine Devonian beds are followed conformably by the nonmarine Knoydart Formation (about 1,000 ft thick) which contains Lower Devonian (upper Downtonian to middle Dittonian) fish remains.
Special studies have also been made of the Bears Brook Volcanic Group and of the structure of the area; repeated movements along the Hollow Fault have resulted in complex folding and faulting in the inland parts of the area.
The village of Arisaig (Fig. 1) lies on Northumberland Strait, 15 mi northeast of Antigonish, Nova Scotia. It is now easily accessible from New Glasgow or Antigonish by Nova Scotia Route 45. The area studied extends along the coast from McAras Brook (3 mi southwest . . .