Search USGS⌕ Search

SEARCH · Search USGS

Results for “Trace Elements Memorandum”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 145 records · Page 8Linked to original sources
USGS1950

Distribution of leached radioactive material in the Legin Group Area, San Miguel County, Colorado

Radioactivity anomalies, which are small in magnitude, and probably are not caused by extensions of known uranium-vanadium ore bodies, were detected during the gamma-ray logging of diamond-drill holes in the Legin group of claims, southwest San Miguel County, Colo. The positions of these anomalies are at the top surfaces of mudstone strata within, and at the base of, the ore-bearing sandstone of the Salt Wash member of the Morrison formation. The distribution of these anomalies suggests that ground water has leached radioactive material from the ore bodies and has carried it down dip and laterally along the top surfaces of underlying impermeable mudstone strata for distance as great as 300 feet. The anomalies are probably caused by radon and its daughter elements. Preliminary tests indicate that radon in quantities up to 10 -7 curies per liter may be present in ground water flowing along sandstone-mudstone contacts under carnotite ore bodies. In comparison, the radium content of the same water is less than 10 -10 curies per liter. Further substantiation of the relationship between ore bodies, the movement of water, and the radon-caused anomalies may greatly increase the scope of gamma-ray logs of drill holes as an aid to prospecting.

Colorado↗
USGS1951

Uranium resources in the Silver Reef (Harrisburg) District, Washington County, Utah

The Silver Reef district is near Leeds, about 16 miles north of St. George, Utah. The major structural feature of the district is the Virgin anticline, a fold extending southwestward toward St 0 George. The anticline has been breached by erosion, and sandstone hogbacks or “reefs” are carved from the Shinarump conglomerate and sandstone members of the Chinle formation, both of Triassic age. Thirteen occurrences of uranium-vanadium minerals, all within the Tecumseh sandstone, which is the upper part of the Silver Reef sandstone member of the Chinle formation, have been examined over an area about l o75 miles wide and 3 miles long. Two shipments of uranium-vanadium ore have been produced from the Chloride Chief and Silver Point claims. Samples from the deposits contain as much as 0.94 percent U 3 O 8 . The ore contains several times as much vanadium oxide as uranium, some copper; and traces of silver. It occurs in thinly bedded cross-bedded shales and sandstones within the fluviatile Tecumseh sandstone member of the Chinle formation. The ore beds are lenticular and are localized near the base, center, and top of this sandstone member. The uranium-vanadium ore contains several yellow and green minerals not yet identified; the occurrences are similar to, but not associated with, the cerargyrite ore that made the district famous from 1879 to 1909.

Utah↗
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↗