coo DESCEIPTIVE GEOLOGY. 



Pass. The liighest point of tliis mountain-mass, however, shows ontcrops 

 of the characteristic quartzitic sandstone of the Weber group, which here 

 seem to be considerably metamorphosed, having a rough trachytic feel, and 

 containing some crystals of quartz and a good deal of decomposed feld- 

 spar. The surfaces of this quartzite show a great deal of slickenside-pol- 

 ishing, evidence of a faulting, which the geological structure of the range 

 renders necessary. The rhy elite, which is the red porphyritic variety already 

 described as common through Nevada, forms flat, table-shaped ridges, which 

 extend down to the banks of the Humboldt below Carlin,andto the eastward 

 obscure the contact between the Weber Quartzites and the Upper Coal- 

 Measure limestones. 



MoLEEN Peak. — The mass of Moleen Peak is made up of nearly hori- 

 zontal limestones, ha"sdng a dip of about 5° to 10° to the southeast, under- 

 laid by quartzites, which have apparently been faulted up into their pres- 

 ent position. Where the canon of the South Fork of the Humboldt cuts 

 through the Elko Range, it exposes about 1,800 feet of these limestones of a 

 prevailing gray and light-blue hue, but with many beds towai'd the bottom 

 of an earthy buff color, and near the top some prominent members of 

 included quartzite. At the three different zones, representing about equal 

 distances through the 1,800 feet, were found the following Coal-Measure 

 fossils : 



From bed No. 1 



From bed No. 2 



From bed No. 3 



Productus suhJiorridus. 

 Productus symmetricus. 



Productus suhhorridus, 

 AtJiyris suhtilita. 

 Spirifer cameratus. 

 Zaphrentis StansburyL 



Productus suhJiorridus. 

 Productus semireticulatus, 

 Productus Prattenianus. 

 Productus symmetricus. 



