Conditions for fossilisation: Killed during an avalanche, Wet, acidic soil, No oxygen, Left undisturbed for long time, Contain hard body parts like bones, Why fossil formation is rare: Decayed by microbes, Most organisms are invertebrates, Destroyed by earth movements, Buried too deep, Limitations in dating method, Radiocarbon dating: Half life is 5730 years, Can date <60,000 years, Organic material , Decay of C-14 to N-14, K-Ar dating: Half life is 1.25 billion years, Can date >100,000 years, Volcanic and igneous rocks, Decay of K-40 to Ca-40 and Ar-40, Relative Dating: Stratigraphy, Fluorine dating, Deeper layers are older, Index fossils, Older fossils have more fluoride ions,

Fossil Dating

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