Nuclear Clocks
The Understanding the Atom Series
Nuclear Energy is playing a vital role in the life of everyman, woman, and child in the United States today. In theyears ahead it will affect increasingly all the peoples of theearth. It is essential that all Americans gain an understandingof this vital force if they are to discharge thoughtfully theirresponsibilities as citizens and if they are to realize fully themyriad benefits that nuclear energy offers them.
The United States Atomic Energy Commission providesthis booklet to help you achieve such understanding.
Edward J. Brunenkant, DirectorDivision of Technical Information
UNITED STATES ATOMIC ENERGY COMMISSION
Dr. Glenn T. Seaborg, Chairman
James T. Ramey
Wilfrid E. Johnson
Francesco Costagliola
by Henry Faul
CONTENTS
- INTRODUCTION 1
- THEORY OF NUCLEAR AGE DETERMINATION 5
- THE CARBON-14 CLOCK 9
- Carbon-14 Counting 12
- Carbon-14 Results 15
- THE LONG-LIVED CLOCKS 19
- The Rubidium-Strontium Clock 20
- The Uranium Fission Clock 24
- Plumbology 27
- THE AGE OF THE EARTH 27
- Analytical Techniques 31
- Minerals That Can Be Dated 34
- SOME INTERESTING RESULTS 40
- The Old Man From Olduvai 40
- The Geologic Time Scale 41
- Precambrian Stratigraphy 47
- AND WHERE DO WE GO FROM HERE? 48
- GLOSSARY 49
- APPENDIX 52
- SUGGESTED REFERENCES 58
United States Atomic Energy Commission
Division of Technical Information
Library of Congress Catalog Card Number: 67-60195
1966; 1968(Rev.)
A 14,000-year-old burial site being uncovered in the area of the Aswan Reservoir in Sudan. To determine the age of such ancient remains, archaeologists search for every scrap of associated wood or charcoal that could be used for age measurement of carbon-14, one of the “nuclear clocks”