Granite Range

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The Granite Range is located northwest of Gerlach, west of Highway 34.

Hague and Emmons write about a 1867 visit as part of the Geological Exploration of the Fortieth Parallel:

"Granite Range.—In the northwest corner of the map, the Granite Range appears as the first mountain uplift in Nevada east of the State of California, its western base lying about 25 miles east of the 120th meridian, the boundary between the two States. The range rises abruptly above the Mud Lake Desert in about latitude 40°45', but projects in a low, narrow tongue of granite 3 or 4 miles still farther to the southward, toward the plain. To the northward, the range stretches far beyond the limits of the Fortieth Parallel Survey, and has never been thoroughly examined or mapped."

"Within the limit of the map, the range extends in a north and south direction for 25 miles in bold, rugged mountains, which rise grandly for 4,000 feet above the level, floor-like plain of Lower Quaternary beds, the highest peaks attaining an altitude of 10,000 feet above sea-level. Only the southern portion of the mountains was visited, but, as far as examined, they appear to consist entirely of granite, with the later Tertiary volcanic rocks breaking out along the base. This granite, in its physical habit, presents all the marked features which characterize the neighboring granitic masses of the Truckee, Pah-tson, and Sah-wave Mountains, but at the same time the range, being higher and more massive, develops certain aspects and modes of weathering which are not so characteristically shown in the more subordinate, narrow ridges. The canons are deeply cut, but the ridges and spurs have in general a rounded outline, in distinction from angular forms, while the peaks, although standing out boldly, have curved, broad, and even dome-shaped summits, and are rarely seen in sharp pinnacles. In general, the granite is characterized by a uniform texture, and shows little tendency to form either a fine or coarse-grained rock. It breaks readily under the blow of a hammer. It is made up of translucent quartz grains, both monoclinic and triclinic feldspars, biotite, and hornblende. All the feldspars are light-colored, and the plagioclase, which is the prevailing fonn, frequently occurs beautifully striated and characterized by a brilliant lustre. Hornblende, as a constituent of the rock, varies very considerably in different localities as to the amount present, but is always a marked feature of the body. Amber-colored titanite, the variety designated as sphene, is very abundant, with well-developed crystalline faces."

"It may be added that the rock-mass possesses a fresh, unaltered appearance, with no recognizable law in the arrangement of the mineral constituents. A specimen collected from the low hills west of Granite Creek Station may be taken as a typical rock. It was subjected to chemical analysis by Prof. Thomas M. Drown, of Lafayette College, with the following result:"

Silica 65.83
Alumina 16.84
Ferrous oxide 3.90
Manganous oxide 0.29
Lime 4.59
Magnesia 1.84
Soda 3.84
Potassa 2.48
Loss by ignition 0.62
100.23

"This analysis bears a close resemblance to that of the Pah-tson Mountain granite, a resemblance which is equally well shown in the lithological characters of the two rocks."

"East of Granite Creek, at the base of the range, occurs an outburst of basalt, rising but a few hundred feet above the desert. It forms smooth, rounded hills of black, compact rock, closely resembling in its geological occurrence the basaltic eruptions flanking the granite bodies of the Truckee and Lake Ranges."[1]


The 1914-1915 WPRR Descriptive Time Table states: "Queer hummocks are scattered over the surface and not far from the tracks at Trego, formerly Trego Springs, are the Double Hot Springs, steamy in winter. The old overland trail passes here. The sharp bluish spurs of the Granite Range, soon to be crossed, are plain ahead on the right. From the Granite Range will be sighted California"[2] Double Hot Springs are many miles from Trego.

References

  1. Arnold Hague and S. F. Emmons, "Vol. II. Descriptive geology," p. 797-799, in Clarence King ed., "Report of the geological exploration of the fortieth parallel," 1877.
  2. "Descriptive Time Tables, Denver and Rio Grande - Western Pacific, Winter 1914-1915."

External Resources