DIAMOND PEAK. 157 



fied from the top of Telegraph Peak at White Pine, where it also occurs 

 not far below the base of the shale. 



At the summit of the Nevada beds a reddish gray, impure limestone 

 passes gradually into the black, argillaceous shales of the White Pine 

 series, the contact between the two formations being admirably shown all 

 along Hayes Canyon at the base of Newark Mountain. The drainage 

 channel marks closely the line of contact. Hayes Canyon lies wholly in 

 the shales, erosion having carved out of them a broad valley, similar in 

 topographical structure to Secret Canyon, between the Prospect Mountain 

 and Hamburg limestones. Upon one side of Hayes Canyon rises a wall of 

 dark blue, Devonian limestone, and on the other light blue and gray Car- 

 boniferous limestone. At the summit of Hayes Canyon the shales follow- 

 ing the course of the limestones of Newark Mountain trend off to the north- 

 east and rapidly pass under Diamond Peak. The relationship between the 

 shales and the Diamond Peak quartzite may be best studied along the base 

 of Bold Bluff, the former being seen to dip conformably beneath the 

 quartzites at an angle of 30. 



Diamond Peak. The summit of Diamond Peak attains the highest eleva- 

 tion of any point within the limits of this survey, reaching an altitude 

 above sea level of 10,637 feet. From Newark Valley it rises for over 4,000 

 feet with an almost unbroken slope to the summit. No peak commands 

 a more favorable view for a study of the relationship between the topo- 

 graphical configuration and geological structure of the country. The 

 structure of the peak is that of a sharp, synclinal fold, the axis of which, 

 striking northeast and southwest, lies along the crest of the ridge. The 

 westerly dipping beds form the entire eastern slope of the peak, exhibiting 

 a great thickness of Devonian and Carboniferous rocks. At the base of 

 the peak, just outside the limits of the map, the Nevada limestone comes 

 in, overlain by a broad belt of black shales, which form the lower slopes, 

 but, as denudation has worn them smooth, they present rather a monoto- 

 nous aspect. Following the shales are the Diamond Peak quartzites, in rough 

 and rugged ridges and bold walls, extending within 1,200 feet of the sum- 

 mit, over which come the massive Coal-measure limestones forming the top 

 of the peak. 



