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,

Bảng xếp hạng

Phong cách trực quan

Tùy chọn

Chuyển đổi mẫu

Bạn có muốn khôi phục tự động lưu: không?