PRIMARY MINERALIZATION OF URANIUM-BEARING "SILICEOUS REEF" VEINS IN THE BOULDER BATHOLITH. MONTANA. PART II. THE VEINS

Journal Article · Tue Mar 01 00:00:00 EST 1960 · Economic Geology and the Bulletin of the Society of Economic Geologists (U.S.)

DOI:https://doi.org/10.2113/gsecongeo.55.2.363· OSTI ID:4181316

Bieler, B H; Wright, H D

The "siliceous reef" uraniferous veins of the Boulder batholith contain, in decreasing order of abundance, finely crystallized pyrite, sphalerite, galena, uraninite, tetrahedrite, argentite, chalcopyrite, and covellite. Microcrystalline quartz comprises over 90 percent of the vein material; opal and barite are minor. The color of the veins varies from light gray to black due to variation in size and concentration of the microscopic grains of opaque minerals. Microcrystalline quartz was deposited in several stages. separaied by intervals of brecciation. Quartz of the later stages is generally dark gray to black. It occurs as fracture fillings in massive early microcrystalline quartz of light color, and as a cementing matrix about breccia fragments of the lighter quartz. The uranium content of nearly one hundred vein samples was determined by alpha counting and fluorimetry. Radioactive equilibrium of the uranium series is indicated by agreement between measured radium content (analyzed by New Brunswick Laboratory, AEC) and that required for equilibrium with uranium determined in two samples. and by general agreement between fluorimetric and alpha-activity- determinations of uranium. Semiquantitative spectrographic analysis of the same samples provided data on the content and distribution of 28 minor elements in the veins In most cases, the darker the vein quartz, the higher is the content of those elements generally occurring in opaque vein minerals: Ag, As, Ba, Co, Cu, Fe, Mn, Mo, Ni, Pb, Sb, Sn, U, and Zn. Elements that showed no significant correlation with vein color are Al, B, Be, Ca, Cr, Cs, Ga, Ge, Mg, Na, P, Sr, Ti, V, and Zr. Five elements-Fe, As, Co, Mo, and Pb-showed a marked positive correlation with uranium. (auth)

• Research Organization: Pennsylvania State Univ., University Park
• Sponsoring Organization: USDOE
• NSA Number: NSA-14-010681
• OSTI ID: 4181316
• Journal Information: Economic Geology and the Bulletin of the Society of Economic Geologists (U.S.), Vol. Vol: 55; Other Information: Orig. Receipt Date: 31-DEC-60
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

GEOLOGY, MINERALOGY, AND METEOROLOGY
ACTINIDES
ALKALI METALS
ALKALINE EARTH METALS
ALPHA DETECTION
ANTIMONY SULFIDES
ARGENTITE
BARITE
BARIUM SULFATES
CHALCOPYRITE
COLOR
COPPER SULFIDES
COVELLITE
CRYSTALS
DISTRIBUTION
ELEMENTS
FLUORESCENCE
GALENA
GRAIN SIZE
IRON SULFIDES
LEAD SULFIDES
MEASURED VALUES
METALS
MINERALS
MONTANA
OPAL
PYRITE
QUANTITY RATIO
QUARTZ
RADIOACTIVITY
RADIUM
SILICON OXIDES
SILVER SULFIDES
SPECTROSCOPY
SPHALERITE
TRANSITION METALS
URANINITES
URANIUM
URANIUM MINERALS
URANIUM ORES
USA
ZINC SULFIDES