Radioactivity in Geology and Cosmology

Abstract

The study of natural radioactivity has experienced a substantial revival in recent years. One reason is the general increase in importance and popu larity of all aspects of nuclear science, with this branch partaking of its share. The practical importance as raw materials for nuclear energy of uranium and thorium, which are the parents of most of the known natural radionuclides, has stimulated a study of the properties and occurrences of the latter. It has also been realized that natural radioactivity is a phenome non of considerably greater variety and more general incidence than had been believed previously (339,340,379). .The well established and newly discovered geological ramifications of the occurrence of radioactivity in nature have induced considerable numbers of earth scientists to employ nuclear tools in their studies. The natural occur I The preparation of this paper has been assisted by the United States Atomic Energy Commission through its support of nuclear chemistry research at Carnegie Institute of Technology. ! The following abbreviations are used in this chapter: dis. (disintegration); m.y. (million years) ; B.P. (before present) .

Gamma-ray measurements of naturally occurring radioactive samples from Cyprus characteristic geological rocks

“…Also, Chang et al (1974) reported the concentrations of thorium, uranium and potassium in earthen building materials of Taiwan to range from 14 to 16 ppm, 1.2 to 4.3 ppm and 0.15 to 12.8%, respectively. Potassium concentrations in a wide variety of rock types are estimated to range from approximately 0.1 to 3.5% (Kohman and Saito, 1954). Very recently, Chiozzi et al (2002) have performed a series of investigations on different rock types at the Alps-Apennines transition, and found elemental concentrations being in the range: 0.3−16.7 ppm, 0.3−5.6 ppm, and 0.14−5.14 %, for thorium, uranium and potassium, respectively.…”

Chemical composition of rivers and lakes

“…This is only a little higher than the mean of all the available analyses of the Mississippi, including those made after treatment which might be expected to lower the radium content, and probably is of the correct order of magnitude. It is worth noting, however, that most people who have studied the matter believe the radium content of rivers to be one complete order of magnitude lower (Holland and Kulp, 1954, 0.35XKT10;Koczy, 1954, 0.7 Xl(r10;Kohman and Saito, 1954, North America only, 0.3X10"10). The present estimate would indicate a Ca/Ra ratio for river water of 5X1010; the earlier estimates, made on less nearly complete data, would indicate a ratio of about 5X1011.…”

Measurement of Terrestrial Gamma Radiation Level and Annual Effective Dose in and Around Nuggihalli-Holenarasipura Schist Belts, Karnataka State, India

“…The indoor absorbed dose rates are higher as compared to outdoor absorbed dose rates except in some locations. Higher levels of indoor absorbed dose rates are mainly due to the use of rocks and building materials for building construction as they contain higher amount of natural radionuclides such as 238 U, 232 Th, and 40 K [22,[26][27]. The use of gneissic granites, soil, and other decorative stones for the construction of walls and floor combined with poor ventilation inside the buildings increase the absorbed dose rates.…”