Thermoluminescence

High energy radiation creates electronic excited states in crystalline materials.

This phenomenon has been applied in the thermoluminescent dosimeter, a device to measure the radiation dose received by a chip of suitable material that is carried by a person or placed with an object.

Subsequent recharging of this material from ambient radiation can then be empirically dated by the equation: Age = (subsequently accumulated dose of ambient radiation) / (dose accumulated per year) This technique was modified for use as a passive sand migration analysis tool (Figure 2).

[1] The research shows direct consequences resulting from the improper replenishment of starving beaches using fine sands.

Beach nourishment is a problem worldwide and receives large amounts of attention due to the millions of dollars spent yearly in order to keep beaches beautified for tourists,[2] e.g. in Waikiki, Hawaii.

Thermoluminescence of fluorite.
Figure 1 : Three stages of thermoluminescence as outlined by Aitken (1985, 1998) and applied to a quartz grain (Keizars, 2008b).
Figure 2 : The process of recharging and discharging thermoluminescent signal, as applied to beach sands. (modified from Aitken, 1998; Keizars, 2008).
Figure 3 : Thermoluminescence signature lost during migration of two sand grain sizes (Keizars, 2008).
Figure 4 : Illustrated method of passively monitoring sand input (Keizars, 2003).
Graph of TSL (thermally stimulated luminescence)