Page 105 - Radiochemistry and nuclear chemistry

CHAPTER 5

Radionuclides in Nature

Contents

5.1. Cosmogenic radionuclides 95
5.1.1. Survey 95
5.1.2. Tritium 96
5.1.3. 14-Carbon 97
5.2. Primordial radionuclides 97
5.2. I. Very long-lived nuclides lighter than lead 97
5.2.2. Elements in the natural radioactive decay series 98
5.3. Transuranic elements in nature and the Np decay series 99
5.4. Thorium 103
5.4.1. Isotopes 103
5.4.2. Occurrence and production 103
5.4.3. Uses 104
5.5. Uranium 104
5.5.1. Isotopes 104
5.5.2. Occurrence, resources and production capacity 104
5.5.3. Production techniques 105
5.5.4. Production wastes 107
5.6. Radium and radon in the environment 108
5.7. Disequilibrium 109
5.8. Age determination from radioactive decay II0
5.8.1. Dating by 14C method III
5.8.2. Dating by K-Ar method 112
5.8.3. Dating by Rb-Sr method 114
5.8.4. Dating based on ~SU decay 115
5.9. Natural radioactivity of the oceans 116
5.10. Anthropogenic radioactivity in nature 117
5.10. I. Nuclear weapons 118
5.10.2. Nuclear power plant accidents I19
5.10.3. Releases from nuclear plants 120
5.10.4. Other anthropogenic additions 120
5.11. Exercises 121
5.12. Literature 121

Practically all natural materials contain radioactive nuclides, though usually in such low
concentrations that they can be detected only by very sensitive analysis. This is true for
water (rain water, rivers, lakes, sea), rocks and soil, and all living matter, as well as for

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