NORTHWEST-SOUTHEAST SERIES 497 



the two formations is a straight line at right angles to the strike of the Newark 

 beds. Along the line of junction the Newark strata dip northwest at angles 

 varying from 30 to 35 degrees. 



"This locality has not been thoroughly studied, but from the reconnaissance 

 made it seems as if the Newark strata had been depressed into the crystalline rocks 

 along the junction of two faults which meet each other at nearly right angles." 



The rectangular " elbow system," so well illustrated by the Susque- 

 hanna and Delaware rivers, includes an upper reach of the latter stream, 

 which is northwest of the city of New York. Its direction continued to 

 the southeast is in approximate correspondence with the buried channel 

 of the Hudson, beginning 10 miles from Sandy Hook and extending 

 with a single brief interruption some 60 miles to seaward.* 



OTHER LINEAMENTS 



Orientation of the three principal series. — The three series of lineaments 

 already described are the meridional series (north 5 degrees east), a second 

 series averaging 50 degrees east of the meridian, and a third series near 

 43 degrees west of the meridian, and here because of their moderate ex- 

 tension and position on the map projection, coinciding in direction with 

 the lines of common azimuth. It must have been noted that there is 

 less correspondence between the rivers outlining lineaments in this series 

 than in the other two. The line along the Saint Johns river has the 

 direction north ± 33 degrees west (see figure 2). The others have been 

 drawn on the map as about north 43 degrees west, but it is noticeable 

 that west of the Appalachians the markedly rectilinear streams which 

 approach their direction have the direction north ± 33 degrees west. 

 The directions north 34 degrees west and north 44 degrees west were 

 found to characterize many faults in the Pomperaug valley, Connecticut, 

 and the same divergence of northwesterly flowing streams is made out 

 on plate 45. With the individual exceptions shortly to be mentioned, the 

 lineaments comprising these three series clearly constitute the stronger 

 tectonic lines of the region — the lines indicated by the larger rivers, the 

 coastline, the formation boundaries, the borders of plateaux, the main 

 mountain ranges, and the boundaries of physiographic provinces. Larger 

 scale maps than the one used would reveal many other directions, and 

 careful search of the map here used as a base would bring out new 

 lineaments, both in the series mentioned and in other series. The aim 

 has been, however, to draw attention to the dominant lineaments onl} r . 



Newark border line. — A tectonic line not strikingly revealed on the 

 small scale topcgraphic map is in southwestern New England and south- 



*A. Lindenkohl : Geology of the sea bottom in the approach to New York bay. U. S. Coast Sur- 

 vey Rept. 1884, Appendix 13, pp. 435-438. 



