The two primary methods used to determine the absolute age of rocks and fossils are:
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Radiometric Dating: This technique measures the decay of radioactive isotopes in materials. By determining the ratio of parent isotopes to daughter isotopes and knowing the half-life of the parent isotope, scientists can calculate the age of the rock or fossil.
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Dendrochronology: This method involves counting tree rings to determine the age of trees. Each ring typically represents one year of growth, allowing researchers to establish timelines for ecological and climatic changes.
While radiometric dating is more commonly used in geology, dendrochronology serves as a valuable tool in specific contexts related to tree growth and environmental studies.