Why can't scientists use radiometric dating methods exclusively to date things?

  • Stratigraphy is used to determine the sequence of geological events by studying rock layers.
  • There are six principles of stratigraphy: uniformitarianism, original horizontality, superposition, cross-cutting relationships, inclusions, and faunal succession.
  • Relative age talks about what is older or younger than something else, while absolute age gives the actual age.
  • There are several methods for finding the absolute age of something, including:
  • Radiometric dating is used to find the absolute ages of rocks and fossils using the radioactive properties of elements (such as uranium) and their known half-lives. Uranium's half-life is 700 million years.
  • Incremental dating provides year-to-year time frames by measuring the addition of new material to older material. Dendrochronology, the study of ice cores, and the study of varves are all types of incremental dating.
  • Correlative dating involves mapping and comparing rocks and fossils in various areas to look for physical continuity, in order to draw conclusions on geologic trends and timeframes