ANT200H5 Lecture Notes - Lecture 9: Piltdown Man, Organic Matter, Accelerator Mass Spectrometry
Document Summary
Dating based on observable changes in artifacts or features through time. Buried bones will lose organic components (mainly nitrogen), and gain inorganic components (e. g. fluorine and uranium at stead rates) The rates vary because of temperature and humidity, therefore the rates are location specific. Only good to determine relative dates: one bone is older/younger than another from the same deposit. *bones can also be used for absolute dating (radiocarbon dating) Relative dating (sequence of past objects) only tells us their age relationship. To explain change you need a better idea from absolute dating. Organic material decays after death the unstable material starts to decay. Half-life: the amount of time it takes half of the atoms of a radioactive isotope to decay e. g. uranium, carbon 14, potassium, etc. Three factors: original amount of radioactive isotope, computed indirectly, the amount now present counted directly, counted directly, the rate of radioactive decay. Tree-ring dating, the most precise of all chronometric dating techniques.
