Explanation of how geologists date rocks (to determine the ages of the Earth, fossils, mineral deposits, and other geologic events) and processes using radiometric dating techniques based on radioactive isotopes of carbon and potassium/argon.
An "image map" periodic table and short notes about many isotopes and their applications to illustrate the uses of assorted isotopes in hydrology, geology, and biology.
Report of research on the Carolina slate belt and gold deposits in Virginia, North Carolina, South Carolina, and Georgia with geologic mapping, mineralogic, geochemical, and fluid evolution studies, radiogenic dating, and stable isotope studies.
Manual of chemical sediment analysis using Coulometer and CHN Analyzers to measure carbon content, spectrometric analysis for biogenic silica, and radiochemistry to measure isotopes. Includes techniques,sample preparation, and safety procedures.
Description of the methods of geochronology used to estimate the dating of rocks and sediments with links to technique, equipment and contacts for a variety of methods.
Booklet giving general explanations of geologic time, major divisions of geologic time, relative and radiometric time scales, index fossils, and the age of the earth.
Services available at the Geological Survey TRIGA Reactor (GSTR) site in Denver with information on irradiation, neutron activation analysis, fission track radiography, and geochronology and tours of the facility.
Site on the Chlorofluorocarbon Laboratory and its analytical services for CFCs, sulfur hexafluoride, dissolved gases including nitrogen, argon, methane, carbon dioxide, oxygen, and helium, and tritium/helium-3 dating.
The USGS Argon-40/Argon-39 Geochronology Laboratory in Denver, Colorado, is a facility for determining the age of rocks and minerals by measuring the proportions of naturally occuring radioactive isotopes to their decay products.
U.S. Department of the Interior |
U.S. Geological Survey