Thermoluminescence dating sediments No credit free sex chat only
Minerals—and, in fact, everything on our planet—are exposed to cosmic radiation: luminescence dating takes advantage of the fact that certain minerals both collect and release energy from that radiation under specific conditions.
Crystalline rock types and soils collect energy from the radioactive decay of cosmic uranium, thorium, and potassium-40.
Luminescence dating is good for between a few hundred to (at least) several hundred thousand years, making it much more useful than carbon dating.
In the simplest cases the light intensity is proportional to the radiation dose and can be used for determining an unknown dose; when combined with other measurements which yield the dose rate the TL can thus be used to calculate an age.In the case of pottery the event being dated is the last heating of the material to a high temperature, typically 500 °C.The use of TL to date the deposition of ocean sediments which we propose here is similar in the main principle except for the lack of the heating event.This energy is lodged in the imperfect lattices of the mineral's crystals.Heating these crystals (such as when a pottery vessel is fired or when rocks are heated) empties the stored energy, after which time the mineral begins absorbing energy again.