496 W. H. HOBBS LINEAMENTS OF ATLANTIC BOREEK REGION 



one has been extended on plate 45. Examination of the official United 

 States map, on which plate 45 is based, will show that throughout the 

 Green Mountain area branch streams largely incline to follow a northwest- 

 southeast direction. On plate 45 the course of a line of this series can be 

 followed from Long Island sound northwestward nearly along the course 

 of the Connecticut below Middletown, along the Farmington river, across 

 the Adirondack region in approximate correspondence with Black river, 

 along which the Adirondack gneiss abuts against the Trenton.* 



Other lines of the series. — Southwestward from the city of New York the 

 courses of the northwest-southeast lineaments are marked out in the 

 Delaware, Susquehanna, Potomac, Cape Fear and Kanawha, and the 

 Savannah rivers. The line 3 is not only the course of a lower section of 

 the Delaware, but it corresponds approximately to the upper course of 

 the Susquehanna for a long distance. Extended, this line would corre- 

 spond approximately to the ancient outlet of lake Huron. The line next 

 south (4) (see plate 45) follows the lower Susquehanna, as the Delaware 

 line does the upper. Another line (5), having approximately the same 

 direction, follows the Potomac, and, in the vicinity of the Great lakes, 

 the Alleghany river. The line 8 is the course of the Cape Fear and 

 Kanawha rivers. Where it crosses the Newark formations on the border 

 of North Carolina it appears to do so through a narrow gorge (a graben 

 or rift valley), which separates the Danville from the Dan River area. 

 Concerning this gorge Russell says : f 



" The Danville area terminates abruptly at the south, and appears to have been 

 separated from the Dan River area by a profound displacement trending northwest 

 and southeast, or at right angles to the prevailing strike of the rocks." 



The northwest-southeasttrending series are of especial interest in their 

 connection with the interruptions of continuity in the Newark system. 

 Attention has already been called to the way in which the Danville and 

 Dan River areas are separated by a displacement along this direction. 

 Hardly less worthy of mention is the indicated lineament which follows 

 the Roanoke river past the city of Weldon, North Carolina, and is 

 extended westward as a marked drainage line. Parallel to this direc- 

 tion and in its neighborhood is a dislocation wdiich Russell thus de- 

 scribes : X 



"The abrupt manner in which the strata at the northeast extremity of the 

 Danville area abut against the crystalline rocks, when followed northwestward 

 along the strike, is well shown near the little hamlet of Cascade. The junction of 



*See Merrill, Geological Map of New York, 1901, Saint Lawrence Sheet, 

 f Loc. cit., p. 86. 

 X Loc. cit., p. 8G. 



