108 ROYAL SOCIETY OF CANADA 



These views would, therefore, make the origin of the Bay of Fundy 

 trough, as well as the associated ridges and depressions, coincident with 

 and the result of the very earliest orogenic movements of which we have 

 an}^ knowledge, and to an}^ one interested in the probable history of this 

 portion of the country, must be regarded as of extreme importance. We 

 have now to inquire how far the}^ are in accordance with our present 

 knowledge. 



In the tirst place it is to be noticed that in recognizing two belts only 

 of Archaean rocks as traversing the Acadian basin, viz., that of northern 

 or central New Brunswick and that of Nova Scotia, the only group or 

 belt of rocks which in the former pi'ovince is known to be of the Pre- 

 Canjbrian age is entirely overlooked ; the great central basin of New 

 Brunswick being at the same time made continuous with the Bay of 

 Fundy trough, from which these Pre-Cambrian rocks now completely 

 separate it. As to the ridges north of the central basin, now occupied by 

 the Coal measures, and dividing the latter from the Gaspe-Worcester 

 trough, it is true that a portion of these have, in the reports and maps of 

 the Geological Survey, been represented as Archaean ; but even if this be 

 their age, of which there is as yet no definite proof, the area which they 

 occupy is not large, and no evidence whatever is available to show 

 that they were connected either on the one side with the rocks of New- 

 foundland, or on the other with those of southern Maine and Massa- 

 chusetts. It seems much more probable that, if Archaean at all, the rocks 

 in question represent one or more of several insular groups in the Cam- 

 brian seas, of which others were to be found in northern Maine, in south- 

 ern New Brunswick and in eastern Nova Scotia. 



If now we consider the facts connected more particularly with the 

 Bay of Fundy trough, we find definite proof not only of the existence of 

 terrestrial areas in this vicinity at the opening of the Cambrian era, but 

 that these were so disposed as to determine a northern border to the 

 trough, not widely different in position from that which now limits it in 

 the same direction. For although among the formations adjacent to the 

 Bay are found representations of all the successive eras, from the Laur- 

 entian to the Trias inclusive, they occup}' in general very small areas, 

 forming a mere fringe, as it were, to the Archa;an ridges, which, for 

 much of their length, rise directly and precipitously from the waters of 

 the bay. That they similarly thus rose in early Cambrian times, or at 

 least that ridges in part above the sea-level were not very distant, is fully 

 shown by the nature and distribution of the Cambrian sediments, by 

 their physical markings and by their contained fossils, as long since 

 pointed out by Matthew. It seems probable, however, that their height 

 was somewhat less to the eastward than to the westward, the Archaean 

 rocks, which to the west of the St. John river form one broad belt, being 

 to the eastward of that stream divided into several, possibly insular, 

 ridges, by intervening parallel troughs of Cambrian sediments. 



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