MOLEEN CANON. 599 



tlie mass are well-defined crystals of black biotite, tlie whole enclosed in a 

 subordinate felsitic groundmass full of crystals of quartz. In the southern 

 half of the River Range, the geological axis has a direction apparently about 

 northeast and southwest, and south of the road from Elko the prevailing 

 dip of the formation is to the eastward. Quartzites and conglomerates form 

 the summit for some distance south of this point, showing occasional beds 

 of limestone, while along the eastern slopes, toward Moleen Canon, are 

 found outcrops of light-colored earthy limestones overlying the quartzites 

 conformably, which correspond to the Upper Coal-Measure limestones 

 found at Moleen Peak, on the opposite side of the river. These are ex- 

 posed in section at the entrance to the canon, where the dip, at first shallow, 

 gradually rises to 45°. A thickness of nearly 2,000 feet of buff, earthy 

 limestones, with some included conglomerates, is thus shown, though not 

 in continuous section, many of the beds being obscured by debris. The 

 strike of the upper beds is considerably to the east of north, but in the canon 

 bends a little to the west of north, where the dip becomes steeper. In the 

 Weber Quartzites, the river takes a sharp bend to the north, returning almost 

 parallel to its course around a ridge of quartzite, whose beds stand almost 

 vertical. In the upper portion of these quartzitos can be recognized the 

 peculiar greenish and purplish conglomerates made up of angular jasper 

 pebbles in a somewhat calcareous matrix, which resemble the conglomerates 

 found along the range to the north, but are less metamorphosed. Although 

 there is a decided appearance of unconformity at this point between' the 

 quartzites and Hmestones, it is probably due to faulting. Underlying the 

 quartzites, on the south side of the river, and dipping about 45° or 50° to 

 the eastward, is a zone of mixed slaty limestones and heavy blue limestones, 

 wliich extend as far west as Carlin. These beds have a strike a little east 

 of north. One of the mud beds above the main mass of limestone, but still 

 some distance below the Weber Quartzites, contains a carbonaceous zone, 

 carrying an impure anthracite. 



These Lower Coal-Measure limestones to the north of the river disap- 

 pear beneath the horizontal Tertiaries of the Maggie Creek Valley. To 

 the south, they are covered by extensive rhyolite flows, which cover the 

 mountain-mass at the northern end of the Piiion Range north of Dixie's 



