304 GEOLOGY OF A PORTION OF SHELBURNE CO., 



Dynamic Geology. 



The first question which arises in considering the dynamical 

 history of the region is the date of the folding and faulting of the 

 pre-Cambrian sediments. The folding probably took place 

 in pre-Cambrian times, and the faulting in the Devonian 

 diastrophism. The goldbearing series is unconformably over- 

 lain by Silurian and by Lower Devonian sediments. 



The effect of the folding of the Goldbearing series, was to 

 produce a series of closely folded anticlines and synclines. The 

 axes of these folds are parallel. In Queens County northeast 

 of Shelburne County, the axes trend in a N 45° E to a N 55° E 

 direction, and this direction is characteristic of axes of folds 

 in Lunenburg and Halifax counties to the east. In Yar- 

 mouth County, on the west of Shelburne, the trend is N 20°- 

 30° E. In Shelburne County, however, the main axes, ac- 

 cording to Dr. Bailey's map, turn toward the Atlantic Ocean 

 in a N 15°-20° E direction. The major axes of the batholiths 

 as shown on the same map, are about N 5° E. In the coastal 

 region considered in this paper, the principal fold's are ob- 

 scured by block faulting*, but the axial direction is N 20° E. 

 It is therefore evident that these axes of mountain-building 

 turn from a S 45° W direction to one of S 20° W, which is 

 toward the Atlantic Ocean and not parallel to the coast line 

 of North America. In "La Face de la Terre" Vol. 1 ffig. 103) 

 Suess and de Margerie plot the tectonic axes of eastern North 

 America, and show the axis of southwestern Nova Scotia turn- 

 ing from a S 65° W direction to one of S 15° E. In view of the 

 above data, it is clear that a turn as great as »0° does not exist. 

 The existing turn is comparable to that of the axis of the 

 Canadian Appalachians into the axis of the Taconic Mount- 

 ains. 



The Goldbearing series throughout Nova Scotia has under- 

 gone extensive metamorphism which appears to be entirely 



♦The favdting is dated, from evidence found elsewhere, as later than the batholithic intrusion, 

 and therefore does not concern the question at hand. 



