OCR Text |
Show SEVIER VALLEYâ€"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 cation through the great monoclinalâ€"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 dimensions. 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 rainbow 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 Pavant, 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 between 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 somewhat exceptional rock ; very little feldspar, much free quartz, and the vesicular specimens have the elongated, wiry, and fluctuated vesicles which are eminently characteristic of rhyolite. The black color, almost equal to that of basalt, is apparently due to the presence of an unusual quantity of magnetite. |