Obsidian hydration dating is based on the fact that

The reliability of the method based on Friedman’s empirical age equation (x²=kt, where x is the thickness of the hydration rim, k is the diffusion coefficient, and t is the time) is questioned from several grounds regarding temperature dependence, square root of time and determination of diffusion rate per sample and per site, apart of some successful attempts on the procedure and applications.The SIMS-SS age calculation procedure is separated into two major steps.In case of measuring the hydration rim using the depth profiling ability of the secondary ion mass spectrometry technique, the sample is mounted on a holder without any preparation or cutting. There are two general SIMS modes: static mode and dynamic mode, depending on the primary ion current density, and three different types of mass spectrometers: magnetic sector, quadrupole and time-of-flight (TOF).Any mass-spectrometer can work in static mode (very low ion current, a top mono-atomic layer analysis), and dynamic mode (a high ion current density, in-depth analysis).Obsidian obeys the property of mineral hydration, and absorbs water, when exposed to air, at well defined rate.

In order to use obsidian hydration for absolute dating, the conditions that the sample has been exposed to and its origin must be understood or compared to samples of a known age (e.g.Although relatively infrequent the use of SIMS on obsidian surface investigations has produced great progress in OHD dating.SIMS in general refers to four instrumental categories according to their operation; static, dynamic, quadrupole, and time-of-flight, TOF.Thus, artifacts exposed to higher temperatures, for example by being at lower elevation, seem to hydrate faster.As well, obsidian chemistry, including the intrinsic water content, seems to affect the rate of hydration.

Search for obsidian hydration dating is based on the fact that:

obsidian hydration dating is based on the fact that-65obsidian hydration dating is based on the fact that-77obsidian hydration dating is based on the fact that-82

Leave a Reply

Your email address will not be published. Required fields are marked *

One thought on “obsidian hydration dating is based on the fact that”