188 



GUIDEBOOK OF THE WESTERN UNITED STATES. 



West of Hafcd, a sidetrack opposite a rancli on the valley bottom, 

 some good examples of columnar jointing in the basalt lava are ex- 

 posed just above the railroad track. (See footnote, 

 p. 121.) Volcanic tuff, both coarse and fine, appa- 

 rently underlies the basalt and forms bluffs. To the 

 west the river channel narrows asjain and is bordered 



Hafed. 



Elevation 4,376 feet. 

 Omaha 1,529 miles. 



on both sides "By steep rocky ridges and spurs. 



Vista, an old station and group of section houses, is at the upper 



end of the canyon in the Virginia Range, and immediately beyond 



it the Truckee Meadows spread out broad and flat. 

 The extreme lower part of the meadows near the 

 entrance to the canyon is marshy, from a cause 

 explained in the footnote on page 189. . The many 



prospects of the Wedekind mining district may be seen in the low 



foothills at the margin of the valley to the north. The district has 



never produced much ore. 



The city of Sparks was named after John Sparks, governor of 



Nevada from 1903 to 1906. Although the second city in 



Vista. 



Elevation 1,395 feet. 

 Omaha 1,532 miles. 



Sparks. 



Elevation 4,225 feet. 



Population 2,500. 

 Omaha 1,536 miles. 



Nevada 



in population, it is primarily a railroad division 

 point and contains the Southern Pacific Co.'s shops 

 and roundhouses. A stop of 15 or 20 mhmtes is 

 usually made at the railroad offices and shops, where 

 a hu2re mountain-climbing locomotive is substituted 



fur the ordinary one. After another stop at the passenger station, 

 three-fourths of a mUe farther on, the train proceeds westward 2^ 

 miles across the open valley to Reno.* 



^ To the westbound traveler the xiew 

 to the rear across the Truckee Meadows 

 toward the narrow gorge by which Truckee 

 lUver p 





through the Virginia Kange 



cormected with 



is suggestive of many events in the geo- 

 logic historj' of this general region. The 

 Yir;riiiia Rani^re illustratea the block-fault 



by short slopes of talus and small allu\'ial 

 fans. These works of erosion and depo- 

 sition, however, do not obscure the fact 



esaen' 



block of the earth's crust, and the valley 

 below, now buried by river flood-plain 



Virginia Range 



S'lerra Nevada 

 (front range) 



Truckee Meadows 



Lava and tuff 



Figure 16. 



cross section 



tion to Truckee Meadows, 



characterizes the ranges 



the Great Basin. 



like 



great wall along the lower edge of the 



almost 



between 



The 



steeper part of the mountain front ia 

 trenched by gulches or canyons and ia 



deposits, is a relatively downthrown 



block 



(See fig. 16.) 

 The mountains around 



the Truckee 



Meadows are broken by a narrow gorge 

 through which Truckee River escapes. 

 This gorge, now deep and narrow and 

 worn into solid rock through the most of 



