SYNONYMS OR RELATED TERMS: amino-acid dating; aminostratigraphy; amino-acid racemization, amino acid racemization CATEGORY: technique DEFINITION: A method of absolute (chronometric) dating which is hoped to fill the gap between radiocarbon dates and potassium-argon dates.
It is used for human and animal bone and other organic material.
Collagen survives long after death and the collagen content of a bone, measured by the amount of nitrogen present, yields information as to its relative date.
The rate of decay is varies with temperature and other aspects of the environment, but collagen dating can only give relative dates for different bone samples from a particular site.
The method is based on the principle that all plants and animals, while they are alive, take in small amounts of rock carvings and engravings, potentially applicable to Paleolithic artifacts with a strong patina caused by exposure to desert dust.
Relative dates may be obtained form time-related chemical changes which occur in bone, especially in fluorine, uranium, and nitrogen.
Still, the most commonly used is SYNONYMS OR RELATED TERMS: radiocarbon dating CATEGORY: technique DEFINITION: The occurrence of natural radioactive carbon in the atmosphere allows archaeologists the ability to date organic materials as old as 50,000 years.
It is fairly reliable for deep-sea sediments as the temperature is generally more stable.
SYNONYMS OR RELATED TERMS: archaeomagnetic intensity dating, archaeomagnetism, palaeointensity dating, archaeomagnetic age determination CATEGORY: technique DEFINITION: A chronometric method used to date objects containing magnetic materials -- especially for buried undisturbed features such as pottery kilns, earthen fireplaces, and brick walls -- which can be compared to known schedules of past magnetic alignments within a region and fluctuations in the earth's magnetic field.