Thermoluminescence is produced by radioactive decay particles (electrons), trapped in mineral grains.Heating the mineral (or exposure to light) releases electrons, and produces a flash of light, setting the clock to 0 (maybe only partial).Any remaining powder is dried and used for radioactivity measurements to complete the dating calculation. When the glue is dry, they are cut into slices 1/4mm thick with a fine diamond blade. Each slice is soaked in acetone after cutting to remove the glue. The remaining core is crushed and used for radioactive analysis to complete the dating calculation.We have 3 fully automated, computer operated Riso Minisys TL readers for measuring the TL.Better still, unlike radiocarbon dating, the effect luminescence dating measures increases with time.As a result, there is no upper date limit set by the sensitivity of the method itself, although other factors may limit the method's feasibility.Faulted and liquefied Lake Bonneville strata in Hansel Valley, VT, record a history of recurrent surface faulting which culminated in the 1934 M6.6 earthquake.
The TL is measured using a sensitive detector called a photomultiplier tube.As sediments are buried longer they progressively acquire more TL from accumulated radiation damage from alpha, beta, and gamma rays and cosmic radiation.If the total amount of radiation dose received can be calculated, and the current dose rate measured, then dividing the total dose by the yearly dose rate will yield a TL age.When a small sample of ancient pottery is heated it glows with a faint blue light, known as thermoluminescence or TL.During its lifetime the pottery absorbs radiation from its environment and it is this which creates thermoluminescence.