2 types of dating fossils
{"Image DocumentName": "Types of radiometric dating", "Image ImageDescription": "Potassium-argon method. K-40 half-life 1.3 billion years. Decays into argon and calcium. Used to date rocks older than 100,00 years old. Uranium-lead method. U-238 half-life 4.5 billion years. Decays into lead-206. Used for rocks more than 10 million years old. Rubidium-strontium method. Rb-87 half-life 49 billion years. Decays into strontium-87. Carbon-14 method.", "Image XResolution": "37", "Image YResolution": "37", "Image ResolutionUnit": "Pixels/Centimeter", "Image Software": "SlidePlayer", "Image YCbCrPositioning": "Centered"}