What is obsidian hydration dating

15-May-2016 03:44 by 7 Comments

What is obsidian hydration dating - Momms live sex chat

The reconstruction of time is a central concern all archaeologists must address in their research; few, however, are fully aware of the potential of all the dating methods at their disposal.

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Archaeologists recognize this and started creating an Effective Hydration Temperature (EHT) model to track and account for the effects of temperature on hydration, as a function of annual mean temperature, annual temperature range and diurnal temperature range.

By measuring the thickness you can easily determine if one artifact is older than another (relative age).

If you can determine the rate at which water diffuses into the glass for that particular chunk of obsidian (that's the tricky part), you can use OHD to determine the absolute age of objects.

The relationship is disarmingly simple: Age = DX2, where Age is in years, D is a constant and X is the hydration rind thickness in microns.

It's nearly a sure bet that everybody who ever made stone tools and knew about obsidian and where to find it, used it.

Obsidian hydration dating typically yields a range of ages for a single chronometric measurement, even after controlling for source chemistry and effective hydration temperature.

Previously published data suggest that this range is due to hydration rate variations caused by variability in the concentration of intrinsic water, and specifically hydroxyl ions, in the obsidian.That new rind is visible and can be measured under high-power magnification (40-80x).Prehistoric rinds can vary from less than 1 micron (µm) to more than 50 µm, depending on the length of time of exposure.Obsidian outcrops all over the world, and was preferentially used by stone tool makers because it is very easy to work with, it is very sharp when broken, and it comes in a variety of vivid colors, black, orange, red, green and clear.Obsidian contains water trapped in it during its formation.At present there is no robust and cost-effective protocol for measuring hydroxyl concentration.