Radiometric dating technique to determine the age of earth materials from the ratio of the radioactive isotopes of uranium-235 or uranium-238 to the lead isotope decay products in the sample. The ratio is compared to the known half-life of the uranium isotopes.
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.
U.S. Department of the Interior |
U.S. Geological Survey