As we learned in the previous lesson, index fossils and superposition are effective methods of determining the relative age of objects. In other words, you can use superposition to tell you that one rock layer is older than another. To accomplish this, scientists use a variety of evidence, from tree rings to the amounts of radioactive materials in a rock. In regions outside the tropics, trees grow more quickly during the warm summer months than during the cooler winter.
Define the experimental outcome derived from antarctica. In brief relative age dating. Many ancient lava flows are most rocks are obtained with different types of events? Study vocabulary!
Relative dating and radiometric dating are used to determine age of fossils and geologic features, but with different methods. Relative dating uses observation of location within rock layers, while radiometric dating uses data from the decay of radioactive substances within an object. Relative dating observes the placement of fossils and rock in layers known as strata.
You can skim the sections on the development of the time scale p. No textbook yet? Use these Web sites instead:. The textbook is not necessarily set up in the same structure as the Reading Guides. You will probably have to pull concepts from different parts of the chapters to answer the questions below.