THORIUM, URANIUM AND POTASSIUM IN SOME SANDSTONES

Journal Article · Wed Jan 01 04:00:00 EST 1958 · Geochim. et Cosmochim. Acta

DOI:https://doi.org/10.1016/0016-7037(58)90028-0· OSTI ID:4317809

Murray, E G; Adams, J A.S.

Thorinm, uranium, and potassium concentrations have been determined in nineteen sands and sandstones by gamma -ray spectrometry, fluorometric uranium analysis, and alpha counting. The samples were selected so that both common and extreme thorium and uranium ratios would be represented. The average and nearly uniform values found in orthoquartzitic, clay-free sands were potassium (as metal) 0.64 plus or minus 0.04%s thorium 1.7 plus or minus 0.1 ppms and uranium 0.45 plus or minus 0.05 ppm, giving a Th/U ratio of 3.8 plus or minus 0.8. The Th/U ratio found is very near to that of average igneous rocks and may represent an independent determination of the average crustal Th/U ratio. Heavy mineral separations on some of the ordinary sands indicate that very little of the thorium, uranium, and potassium in a common sand is associated with the heavy detrital grains. Neglecting a very minor feldspar content, the radioactivity of the common sandstones studied is contained almost entirely in the quartz, where it appears to be largely related to microscopic and submicroscopic inclusions. The heavy detrital minerals do not begin to affect the Th/U ratio or concentration ratios until they occur in large quantities as in placer sands. Within experimental error, the modern beach sands studied were in radioactive equilibrium. These preliminary data provide some independent and experimental comparisons for the average thorium and uranium content of sandstones calculated from geochemical balances. The data are also helpful in constructing models of the changes in thorium and uranium ratios that might be observed in moving from a beach line through shallow water sediments to deep-water sediments. (auth)

• Research Organization: Originating Research Org. not identified
• NSA Number: NSA-12-009168
• OSTI ID: 4317809
• Journal Information: Geochim. et Cosmochim. Acta, Journal Name: Geochim. et Cosmochim. Acta Vol. Vol: 13
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

COAST
FLUOROMETRY
GAMMA SPECTROMETERS
GEOCHEMISTRY
IGNEOUS ROCKS
MINERALOGY, METALLURGY, AND CERAMICS
MOTION
PLACERS
POTASSIUM
QUANTITY RATIO
RADIOACTIVITY
SAND
SANDSTONES
SEA
SEDIMENTS
THORIUM
URANIUM
WATER