15: Understanding Earth's History Last updated Save as PDF Page ID5574 Contributed by CK12CK12 15.1: How Fossilization Creates Fossils15.2: Types of Fossilization15.3: Earth History and Clues from Fossils15.4: Understanding Earth's History- Challenge 115.5: Principles of Relative Dating15.6: Determining Relative Ages15.7: Correlation Using Relative Ages15.8: Geologic Time Scale15.9: Understanding Earth's History- Challenge 215.10: Tree Rings, Ice Cores, and Varves15.11: Radioactive Decay as a Measure of Age15.12: Radiometric Dating15.13: Age of Earth15.14: Understanding Earth's History- Challenge 3