SEVIER VALLEY— THE PAVANT. 



171 



Sevier Plateau. The lava, the desolation, and the salt strongly suggest 

 recollections of Sodom and Gomorrah. At this point Salina Creek emerges 

 from its canon through the great monoclinal— a fine, large stream. To the 

 south-southwest the valley of the Sevier becomes considerably narrower 

 and the Pavant lower, but the slope of that range gives place to an abrupt 

 wall, due to a fault. A few miles south of Salina commences the great 

 Sevier Plateau on the east side of the valley, its northern end gradually 

 and steadily sloping upwards as we proceed south and its western wall 

 becoming more and more abrupt, until it becomes a cliff of grand dimen- 

 sions. From the town of Richfield, 18 miles south of Salina, we may 

 behold it in all its grandeur, rising 5,800 feet above the plain below; its 

 upper third a sheer precipice, the lower two-thirds plunging down in steep 

 buttresses which thrust their bases beneath the level floor. Its aspect is 

 dark and gloomy from the dark gray dolerites and trachytes which make 

 up its whole mass Right at our backs are the lively tints of the Tertiaries 

 in the Pavant; beds of pink, carmine, and cream, alternating with almost 

 pure white, and with a rigorously even stratification. A stronger contrast 

 it is difficult to imagine. Yet a mile or two beyond Richfield these rain- 

 bow beds suddenly give place to a black rhyolite,* which has spread from 

 some unknown vent and covered the Tertiaries. 



Moving still southwards along the flank of the Pdvant, which slowly 

 but steadily diminishes in altitude, we reach its junction with the Tushar 

 about 16 miles southwest of Richfield. Here a lateral valley from the 

 west joins the Sevier Valley, the upward continuation of the latter being 

 due south Jietween the towe ing heights of the Sevier Plateau on the east 

 and the Tushar on the west. The separation of the Pavant from the 

 Tushar is merely a low divide or saddle, or, if the idea is more acceptable, 

 the former may be regarded as the northern continuation of the latter at a 

 lower altitude. The lateral valley, as we ascend, narrows rapidly to a mere 

 canon, and from is southern brink rise the great spurs of the Tushar. 



The northern portion of this uplift is crowned by volcanic peaks, 



* This is a soniewliat exceptional lock ; very little feldsijar, nmcli free quartz, and the vesicular 

 specimeus have the elongated, wiry, and fluctuated vesicles which are emiueutly characteristic of rhy- 

 olite. The black color, almost equal to that of basalt, is apparently due to the presence of an unusual 

 quantity of magnetite. 



