1. Radiometric Dating: This method relies on the radioactive decay of certain elements within the rock. Radioactive isotopes decay at a predictable rate, known as their half-life. By measuring the ratio of parent isotope to daughter isotope, scientists can calculate how much time has passed since the rock crystallized.
2. Relative Dating: This method doesn't provide a specific age but rather determines the relative age of a rock compared to other rocks. It relies on the principles of stratigraphy, which studies the layering of rocks. By observing the order of layers, fossils, and other features, geologists can infer the relative ages of different rock units.
It's important to note that while radiometric dating gives a numerical age, relative dating provides a sequence of events. Both methods are valuable tools for understanding Earth's history.
