What is the difference between relative dating and radiometric dating Asia free chat
Some of the most useful fossils for dating purposes are very small ones.
For example, microscopic dinoflagellates have been studied and dated in great detail around the world.
Relative dating and radiometric dating are used to determine age of fossils and geologic features, but with different methods.
Relative dating observes the placement of fossils and rock in layers known as strata.
Isotopes are important to geologists because each radioactive element decays at a constant rate, which is unique to that element.Different species of ammonites lived at different times within the Mesozoic, so identifying a fossil species can help narrow down when a rock was formed.Correlation can involve matching an undated rock with a dated one at another location.Some fossils, called index fossils, are particularly useful in correlating rocks.For a fossil to be a good index fossil, it needs to have lived during one specific time period, be easy to identify and have been abundant and found in many places. If you find ammonites in a rock in the South Island and also in a rock in the North Island, you can say that both rocks are Mesozoic.
Correlation with them has helped geologists date many New Zealand rocks, including those containing dinosaurs.