158 



GUIDEBOOK OF THE WESTERN UNITED STATES 



therefore subsequent to these lava flows in date. The present ranges 

 in the Great Basin are therefore young compared with mountains in 

 general. They are supposed to have been uplifted by movements 

 that lasted at least through a part of Tertiary time and perhaps have 

 extended to the present day. The earth breaks or faults along which 

 ^ the mountain blocks were upheaved are still recognizable at many 

 places in the toj^ographic form of the mountains. 



As a supply or trading point Lucin is now largely superseded by 

 Tecoma, a considerable settlement a few miles farther west. Of the 



mines in the Lucin district/ south of Tecoma, only 



the Copper Mountain mine has lately shipped much 



ore. This mine is connected with the railroad by a 



6-mile spur track and an aerial (wire cable) tramway. 



Stock raising is now the principal industry in this region^ but north 



of the railroad there are some large land holdings which are to be 



subdivided and utilized under a private irrigation project.! 



After ascending the drainage channel above Lucin, the raikoad 

 passes out into a broader and more open valley through which the track 



Tecoma, Nev. 



Elevation 4,807 feet. 

 Omaha 1,114 miles. 



heads straightaway toward Montello. In this valley th 



e r 



aih'oad 



reaches the elevation of the uppermost water level of the former Lake 

 Bonneville, but traces of the old lake shores are not readily discerned. 

 Montello is a railroad town and the first freight terminal west of 

 Ogdcn. The characteristic Nevada or Great Basin scenery is well dis- 

 played here, steep mountain ranges %nth rugged 

 dechvities contrasting sharply with the broad, gentle 

 slopes of rock waste and gi'avel from which they pro- 

 ject. 



Montello- 



Elevation 4,878 feet. 



Population :i55.* 

 Omaha 1,120 miles. 



The railroad winds in and out among s 



uch 



ranges all the way across Nevada, generally finding 

 low passes through them or going around the end of the ranges. 



Leaving Montello the road begins the steeper climb by which it 

 passes over the divide and out of the Bonneville Basin. The highest 



Lini 



Ombe or Pilot Range, a few miles south 

 of Tecoma. Ore was discovered in the 

 district ahout 1869, and there was a con- 

 siderable output of silver and lead until 

 about 1876, after which the district wa3 

 nearly deserted. The increasing demand 

 for copper in recent years has encouraged 

 the development of the copper deposits 

 in the Lucin district, and the value of 

 the copper produced there from 1906 

 to 1912, inclusive, was 



t 



,000. 

 aedimenta 



approxima 



are chiefly of Carboniferous age. They 



rocks 



consist of a coarsely porphyritic rock of 

 granitic character (quartz monzonite por- 

 phyry). The black rocks seen from the 

 railroad at the north end of the range are 

 basaltic lavas. 



The ore bodies, which embrace copper 

 deposits and lead-silver deposits, have 

 resulted from the replacement of lime- 

 stone adjacent to faults and fissures. The 

 copper ores are oxidized, no sulphides 

 ha\'ing yet been reached. The lead- 

 silver ores are also oxidized. Wulfen- 

 ite, the yellow molybdate of lead, is 

 abundant, and the district is probably 

 best known to mineralogists for the beau- 



varioua kinds, the larger bodies of which 



this 



that 



