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Garland B. Gott

Publications and source records attributed to Garland B. Gott.

10 recordsLinked to original sources
USGS1975

Possible extension of mineral belts, northern part of Coeur d'Alene district, Idaho

The ore deposits in the northern part of the Coeur d'Alene district are located within rocks of the Belt Supergroup that have been intruded by Cretaceous quartz monzonites. Lead-zinc-silver replacement veins constitute most of the deposits. The geometry of the district has been modified by post-ore faulting along the Osburn, Dobson Pass, and other faults. The original position of the Gem stocks, before their separation from the Diego Peak stocks by the Dobson Pass fault, can be approximately reconstructed by moving the truncated stocks and associated geochemical dispersion patterns back into matching positions. The known mineral belts are defined by dispersion patterns of both lead and the Pb:Zn ratio. Similar dispersion patterns of lead and the Pb:Zn ration northwest of the original position of the Gem stocks suggest that the mineral belts extend into that area.

Idaho↗
USGS1974

Coloradoite, acanthite, and jarosite from the Cripple Creek district, Teller County, Colorado

Coloradoite (HgTe), acanthite (Ag 2 S), and jarosite (KFe 3 (S0 4 ) 2 (OH) 6 ) have been identified in rocks from the Cripple Creek district, Colorado. Neither acanthite nor jarosite has previously been reported from this mining district. Although the occurrence of coloradoite was reported, its identification was never actually verified. The presence of acanthite may explain a discrepancy between the relative proportions of gold and silver as shown by mill reports and geochemical data.

Colorado↗
USGS1970

Geophysical studies of the Cripple Creek mining district, Colorado

Integrated geophysical, geochemical, and geological interpretations expand the knowledge about the localization of the ore deposits in the Cripple Creek district, Colorado. The principal gold deposits occur in a Tertiary volcanic subsidence basin within Precambrian granite, gneiss, and schist. The basin is filled with volcanic breccia and is intruded by dikes and irregular masses of phonolite, latite-phonolite, syenite, trachydolerite, and basalt. The volcanic complex gives rise to a broad 10 mgal gravity minimum anomaly upon which are superimposed local minima believed to be related to deep mineralized fissure zones. A negative magnetic anomaly over the volcanic subsidence basin probably reflects the degree of alteration of rocks in the subsurface. Two local closed magnetic lows may represent highly altered volcanic centers in the bottom of the basin. The gravity and magnetic anomalies of the basin correlate geographically with positive geochemical anomalies for gold, silver, and tellurium. Just east of the volcanic basin, a prominent negative magnetic anomaly and a corresponding gravity low may represent an altered zone in the granite subsurface.

Colorado↗
USGS1952

Reconnaissance of uranium and copper deposits in parts of New Mexico, Colorado, Utah, Idaho, and Wyoming

Because of the common association of uranium and copper in several of the commercial uranium deposits in the Colorado Plateau Province, a reconnaissance was made of several known deposits of copper disseminated through sandstone to determine whether they might be a source of uranium. In order to obtain more information regarding the relationship between copper, uranium and carbonaceous materials, some of the uraniferious asphaltrite deposits in the Shinarump conglomerate along the west flank of the San Rafael Swell were also investigated briefly. During this reconnaissance 18 deposits were examined in New Mexico, eight in Utah, two in Idaho, and one each in Wyoming and Colorado. No uranium deposits of commercial grade are associated with the copper deposits that were examined. The uraniferous asphaltites in the Shinarump conglomerate of Triassic age on the west flank of the San Rafael Swell, however, are promising from the standpoint of commercial uranium production. Spectrographic analyses of crude oil, asphalt, and bituminous shales show a rather consistent suite of trace metals including vanadium, nickel, copper, cobalt, chromium, lead zinc, and molybdenum. The similarity of the metal assemblage, including uranium of the San Rafael Swell asphaltites, to the metal assemblage in crude oil and other bituminous materials suggests that these metals were concentrated in the asphaltites from petroleum. However, the hypothesis that uranium minerals were already present before the hydrocarbons were introduced and that some sort of replacement or uranium minerals by carbon compounds was effected after the petroleum migrated into the uranium deposit should not be disregarded. The widespread association of uranium with asphaltic material suggests that it also may have been concentrated by some agency connected with the formation of petroleum. The problem of the association of uranium and other trace metals with hydrocarbons should be studied further both in the field and in the laboratory.

Colorado;Idaho;New Mexico;Utah;Wyoming↗
USGS1951

Garo uranium deposits, Park County, Colorado

The uranium deposits, three-fourths of a mile south of Garo, Park County, Colo., were mined over 30 years ago for radium ore. The old workings are now abandoned and inaccessible. Forty tons of ore that contained 1.0 percent uranium are reported to have been mined from two light-gray sandstone beds that are stratigraphically about 100 feet apart. The minerals reported to occur in these sandstones are carnotite, malachite, azurite, calciovolborthite, and volborthite. The deposits are in close proximity to a radioactive cherty limestone which is one foot thick, that contains as much as 0.01 percent uranium. The uranium in the carnotite and the uranium in the chert may be genetically related. Mr. ¥. H. Gaddis of Hartsel, Colo., has recently attempted to reopen some of the workings, but as of April 1951 this operation had not revealed any significant new data. Future prospecting should be initiated in the two sandstone beds that have been mineralized. The chert can be used as a marker bed in correlating the sandstones from one exposure to another.

Colorado↗
USGS1950

The Leyden uranium prospect, Jefferson County, Colorado

The Leyden uranium prospect is in sec. 28, T, 2 S., R. 70 W, Jefferson County, Cplo, Examination of the property was made in February 1950. Uranium was first reported in this locality in 1875 by Captain E. L. Berthoud, who noted uranium minerals associated with the main coal bed. The Old Leyden coal mine workings have long been abandoned and caved, but specimens of the uranium-bearing rock can be seen on the old dump 700 feet to the south. The mineralized coal bed is 10 to 12 feet thick and occurs near the base of the Laramie formation of Upper Cretaceous age. Uranium minerals are present in the form of yellow incrustations and inclusions in fractured and partly silicified coal. Petrographic studies indicate that the silica and uranium minerals were deposited after deposition and carbonization of the coal. Secondary uranium minerals also were found by C. R. Butler along the outcrop of the sandstones in the Laramie formation. No uranium minerals were found in place by the writer, but four samples from the dump contained 0.001, 0,005, 0.17 and 0.69 percent uranium.

Colorado↗