Osl dating range - Mungo Archaeology | Understand Mungo | Visit Mungo.


All sediments and soils contain trace amounts of radioactive isotopes of elements such as potassium , uranium , thorium , and rubidium . These slowly decay over time and the ionizing radiation they produce is absorbed by mineral grains in the sediments such as quartz and potassium feldspar . The radiation causes charge to remain within the grains in structurally unstable "electron traps". The trapped charge accumulates over time at a rate determined by the amount of background radiation at the location where the sample was buried. Stimulating these mineral grains using either light (blue or green for OSL; infrared for IRSL) or heat (for TL) causes a luminescence signal to be emitted as the stored unstable electron energy is released, the intensity of which varies depending on the amount of radiation absorbed during burial and specific properties of the mineral.

In Australia there has been very little evidence found of large scale hunting of megafauna. At Cuddie Springs , a shallow ephemeral lake near Carinda, in semiarid New South Wales, the remains of megafauna animals have been found in association with Aboriginal artefacts and evidence of Aboriginal occupation, hearths and stone tools that still have traces of blood and hair on them. Comparison of DNA from the bones of megafauna animals and the traces on the stone artefacts shows that they were used to butcher Macropus titan (a giant kangaroo) and Diprotodon . So at least at this place the Aboriginal People were eating megafauna animals. It is usually accepted that the giant kangaroo, Macropus titan , went extinct. There are those who believe that rather than becoming extinct, they simply down-sized, evolving into the Eastern Grey Kangaroo, Macropus giganteus , also known as the Great Grey Kangaroo, the largest of which get about 2/3 of the size of Macropus titan .


Osl dating range

Osl dating range