Osl dating sediments dating with married women

Luminescence dating is good for between a few hundred to (at least) several hundred thousand years, making it much more useful than carbon dating.The term luminescence refers to the energy emitted as light from minerals such as quartz and feldspar after they've been exposed to an ionizing radiation of some sort.The energy released by stimulating the crystals is expressed in light (luminescence).

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It is this signal that is the key to luminescence dating techniques.

Given an estimate of the rate of received ionizing radiation (the dose rate, or D), and knowing the total accumulated dose (the palaeodose; designated D This accumulated signal results in luminescence (i.e.

When a geological sediment is buried, the effects of the incoming solar radiation are removed.

With this bleaching effect removed, the influence, albeit often weak, of naturally-occurring radioactive elements (primarily potassium-40, uranium and thorium) within the sediment together with incoming cosmic rays results in the accumulation of a signal within individual mineral grains (most commonly quartz and feldspars).

Electrons from these substances get trapped in the mineral's crystalline structure, and continuing exposure of the rocks to these elements over time leads to predictable increases in the number of electrons caught in the matrices.

But when the rock is exposed to high enough levels of heat or light, that exposure causes vibrations in the mineral lattices and the trapped electrons are freed.

TL dating is a matter of comparing the energy stored in a crystal to what "ought" to be there, thereby coming up with a date-of-last-heated.

In the same way, more or less, OSL (optically stimulated luminescence) dating measures the last time an object was exposed to sunlight.

During the 1960s and 70s, the Oxford University Research Laboratory for Archaeology and History of Art led in the development of TL as a method of dating archaeological materials.

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