DIAMOND KANGB. 549 



SECTION V. 



DIAMOlsD AND PlS^ON RANGES. 

 BY AENOLD HAGUE. 



Diamond Range. — This uplift lies next west of the Humboldt Range, 

 on the west side of Huntington Valley. It is a long single ridge, of which 

 only about 14 miles, at the northern end, comes within the limit of the map, 

 the range terminating abruptly at Railroad Canon, about latitude 40° 10.' 

 It rises from 2,000 to 2,500 feet above the adjoining valleys, of nearly 

 equal elevation above sea-level, in a number of rounded limestone summits 

 with somewhat steep slopes. But little opportunity was afforded for the 

 study of the range, which was crossed at only two points, Chokup Pass, a 

 mile below the boundary of the map, and at Railroad Cation. 



Structurally, this portion of the Diamond Range would appear to be an 

 anticlinal ridge, with the strata trending obliquely across the topographical 

 axis of the range; that is, striking northwest and southeast, both sides of the 

 fold being largely made up of dark bluish-gray limestone. This limestone 

 has been referred to the Lower Coal-Measure formation, the upper member 

 of the Wahsatch group. At Chokup Pass, a depression in the ridge, the lime- 

 stones are seen dipping both east and west at high angles, the axis of the 

 fold occurring along the summit. In the limestone occurs a belt of coarse, 

 although compact, brownish-yellow sandstone, not unlike the sandstone 

 body at White Pine, which lies at the base of the Coal-Measure limestone. 

 It measures nearly 300 feet in thickness. No fossils were found. 



At Railroad Canon, the rocks, light cream-colored limestones dipping 

 to the eastward, are much disturbed and plunge rapidly beneath the surface, 

 where they are overflowed to the north by large fields of basalt. On the 

 eastern edge of the hills is an obscure development of yellowish- white rhyo- 

 litic tufa, showing distinct strata- planes, and having feldspars greatly decom- 

 posed. Quartz is rare, and, when present, is in large pieces penetrated by 



