Definition of luminescence dating

Quand ils sont ensuite soumis à une forte température (250 à ), ils restituent l'énergie accumulée sous forme de lumière (photons). Les cristaux présents dans les matériaux utilisés pour la confection de poteries restituent la totalité de la charge énergétique accumulée au cours du temps géologique lors de leur cuisson.

Pour dater la cuisson de cette poterie, il suffit ensuite de soumettre un échantillon une nouvelle fois à une température élevée : la quantité de lumière émise est proportionnelle au temps écoulé entre les deux opérations.

Luminescence dating utilises energy deposited in mineral lattices by naturally occurring ionising radiation to record information encoding chronology, depositional process information, and thermal history records in ceramics, lithics, and sedimentary materials.

The information is stored through charge trapping processes in populations of point defects in common minerals, and can be reset by heating (for ceramics and heated lithic materials) and/or exposure to light (for sediments and exposed rock surfaces).

The resulting data, in the form of a calibration curve, is now used to convert a given measurement of radiocarbon in a sample into an estimate of the sample's calendar age.

Other corrections must be made to account for the proportion of throughout the biosphere (reservoir effects).

La mesure peut être faussée par tout événement inconnu qui aurait chauffé fortement l'échantillon, comme un incendie.

The method was developed by Willard Libby in the late 1940s and soon became a standard tool for archaeologists.

Research has been ongoing since the 1960s to determine what the proportion of in the atmosphere has been over the past fifty thousand years.

Radiocarbon dating is one kind of radiometric dating, used for determining the age of organic remains that are less than 50,000 years old.

For inorganic matter and for older materials, isotopes of other elements, such as potassium, uranium, and strontium, are used.

any method of determining the age of earth materials or objects of organic origin based on measurement of either short-lived radioactive elements or the amount of a long-lived radioactive element plus its decay product.

A method for determining the age of an object based on the concentration of a particular radioactive isotope contained within it.

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