Bulletin of the United States Geological SurveyThe Survey., 1907 |
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50 feet abundant Alaska alaskite alluvium altered Amargosa Amargosa River andesite appears assay basalt Beatty biotite Black Butte bodies breccia Bullfrog Bullfrog district calcite changes in dip Columbia Mountain Combination copper country rock dacite deposits depth dikes east Eldorado Canyon eruptions exposed fault feet deep feldspar fissures Florence flows formation gneiss gold Goldfield district granite hills hornblende horsepower intrusive irregular January Jumbo lake beds latite lease ledge matter limestone lode Manhattan mass miles mill mineral Montgomery-Shoshone nearly northeast northwest occurs olivine Olivine basalt Original Bullfrog ounces outcrops oxidized pay shoots phenocrysts porphyry pre-Tertiary rocks probably pyrite Quartette quartz monzonite quartzite reconnaissance Redtop region Reilly rhyolite rich Sandstorm schist Searchlight shaft shattered shown shows siliceous silicified silver slope southeast southwest Spurr stoped structure sulphide surface tetrahedrite thickness tion Tonopah town tuffs tunnel U. S. Geol usually vein vertical vicinity zone
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Seite i - B 303. Preliminary account of Goldfield, Bullfrog, and other mining districts in southern Nevada, by FL Rausome, with notes on the Manhattan district, by GH Garrey and WH Emmons.
Seite iv - Underground waters of Tennessee and Kentucky west of Tennessee River and of an adjacent area in Illinois, by LC Glenn.
Seite i - B 293. A reconnaissance of some gold and tin deposits of the southern Appalachians, by LC Groton, with notes on the Dahlonega mines, by W.
Seite 97 - The classes numbered 2, 7, and 8 are sold at cost of publication; the others are distributed free. A circular giving complete lists can be had on application. Most of the above publications can be obtained or consulted in the following ways: 1. A limited number are delivered to the Director of the Survey, from whom they can be obtained, free of charge (except classes 2, 7, and 8), on application. 2. A certain number are delivered to Senators and Representatives in Congress, for distribution. 3. Other...
Seite iv - Lee. 1906. 28 pp. 6 pis. B 297. The Yampa coal field, Routt County, Colo., by NM Fenneman, Hoyt S. Gale, and MR Campbell. 1906.
Seite 45 - Close examination of the contacts, however, shows that the rhj'olite was fluid after the basalt had solidified. Little tongues of rhyolite penetrate the darker rock. The flow banding of the rhyolite, moreover, conforms locally to the surfaces of the basalt masses. That the apparent dikes are really inclusions is certain, but no satisfactory explanation has yet been found for their vertical attitude in a flow that must have had a generally horizontal movement or for the source of the basaltic material.
Seite i - Ore deposits of the Silver Peak quadrangle, Nevada, by JE Spurr. 1906. 174 pp., 24 pis. B 289. A reconnaissance of the Matanuska...
Seite 38 - No. 3 shaft, which afforded about 309 tons valued at $159,000, or $514 per ton. Approximately 59 tons of this averaged, according to Supt. Edgar A. Collins, 54.8 ounces of gold per ton, which is equivalent to a value of nearly $1,100. This ore, which was oxidized, contained only 1 ounce of silver to each 20 ounces of gold. Mr. JE Spurr0 estimated in 1904 that the average value of the ores mined in the Goldfield district was from $200 to $300 per ton or more. In 1905 the average value of shipping...
Seite 54 - All the ore thus far mined or opened is more or less oxidized and, as a rule, contains no sulphides. In the Original Bullfrog mine there is a little chalcocite( or copper glance, and in some undeveloped veins in the schists south of Beatty there are specks of galena, but the only sulphide thus far found in the other deposits is pyrite. Native gold, alloyed with various proportions of silver, is the only valuable constituent of most of the ores, although cerargyrite, or horn silver, is fairly abundant...
Seite 40 - Ludlow, Cal., on the Atchison, Topeka and Santa Fe Railway, by way of Death Valley. Railway connection is projected, also, between the Bullfrog and Goldfield districts. The principal town is Rhyolite, situated at the south base of a short east-west range of hills that connects the Funeral or Grapevine Mountains on the west with Bare Mountain and other irregular groups of peaks, ridges, and mesas on the east, and separates the Amargosa Desert on the south from a similar desert basin extending northward...