| Abstract: | Fundamental principles of thermoluminescence (TL) and the special role of TL in uranium exploration techniques are given in this paper with examples from Australia illustrating its application.TL can be used in two ways in uranium exploration. The first usage stems from the property of minerals capable of TL, to act as dosimeters accounting for charging of available traps by ionizing radiation. The second usage relates to ionizing radiation interfering with the crystal structure of the host mineral and thereby changing the capability for TL. Studies at the Beverley and Westmoreland uranium deposits utilize this second property.At Beverley a continuous drop in TL intensity is observed upon approaching the orebody with TL intensity at a minimum within the orebody. Recognition of ore type TL glow curves and sensitized (or marginal) TL glow curves within the area surrounding the orebody have enlarged the exploration target beyond that of the orebody and its associated radiometric halo.Traverses examining the variations in glow peak intensities, ratios and temperatures across the Junnagunna orebody at Westmoreland show that the glow peak intensity of the high-temperature glow peak increases, that of the low-temperature peak fluctuates though generally decreases, the high temperature/low-temperature glow peak ratio increases upon approaching the orebody. The high-temperature glow peak temperature is at a minimum within the orebody. Similar variations detected nearby may indicate further potential exploration sites.An example from an unmineralized area at Bremer River has indicated a lack of widespread radiation sensitization indicating the unsuitability of the area for economic uranium accumulation. |
