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M.G. White

Publications and source records attributed to M.G. White.

8 recordsLinked to original sources
USGS1953

Reconnaissance for radioactive deposits in the lower Yukon-Kuskokwim Highlands region, Alaska

Investigations in 1947 in the Lower Yukon-Kuskokwim region, Alaska found that previously reported radioactivity in the vicinity of Flat is due to uraniferous zircon, an accessory mineral in monzonite. The monzonite intrudes mafic igneous and Upper Cretaceous sedimentary rocks. The maximum equivalent-uranium content of the zircon is 0.14 percent, and the average content is probably near 0. 13 percent. Chemical analysis of one sample of the most radioactive zircon indicates approximately 0.12 percent uranium and 0.03 percent thoria. The radioactive elements apparently are most commonly associated with reddish-brown inclusions within the zircon crystals. Tests of sulfide-bearing veins, black shales, and other rock types in the area around Flat showed no significant amount of radioactive material. Although there is little likelihood of finding high-grade uranium deposits in the area covered by the 1947 investigation, the fact that the predominant radioactive element in the monzonite is uranium may indicate that other intrusives of the same age in the Lower Yukon-Kuskokwim region might also contain uraniferous material. Possibilities of concentrations in attendant contact-metamorphic or vein deposits are suggested by a previously reported occurrence of zeunerite in a copper lode in this same general belt of intrusives.

Circular↗
USGS1952

Preliminary summary of reconnaissance for uranium on the Seward Peninsula, Alaska, During 1951

Reconnaissance examinations for uranium were made at nine localities in the York, Nome, and Koyuk districts of the Seward Peninsula, Alaska, during .the 1951 field season. In addition carborne radiometric traverses were made of four roads in the Nome and Council districts. Only at Brooks Mountain in the York district are uranium-bearing deposits that required detailed study. On the southwest flank of Brooks Mountain, zeunerite occurs as a surface coating on quartz-tourmaline veins occupying joint fractures in granite| at a second locality, also on the southwest flank of the mountain, zeunerite is disseminated in a highly-weathered, altered zone of granite near a contact with limestone. Preliminary radiometric analyses show an average of about 0.05 percent equivalent uranium in the vein material and about 0.07 percent equivalent uranium in the weathered, altered granitic zone.

Alaska↗