[New color-photographic observation of thermoluminescence of sliced rock samples].
New observation technique has been established for the thermoluminescence photography using extremely high-sensitive color films. Considering future application to the geological fields, a granite was selected as a testing material. The sliced specimens (0.5- 0.7 mm in thickness), which were irradiated with a 60Co source, were mounted on the heater attached with a thermocouple, which was connected to a microcomputer for measuring the temperature. The samples were heated in the temperature range of 80-400 degrees C by operating the camera-shutter controlled with the microcomputer. Four commercially available films (Kodak-1000(ASA), -400, Sakura-400, Fuji-400) could give apparently detectable color-images of artificial thermoluminescence above a total absorbed dose of 880 Gy(88 krad). The specimens, irradiated upto 8.4 kGy(840 krad), allowed easily to distinguish the distinct appearance of the thermoluminescence images depending on kinds of white mineral constituents. Moreover, such color images were changeable with the heating temperature. Sakura-400 film has proved the most colorful images from aspects of color tone although Kodak-1000 film showed the highest sensitivity. By applying this Kodak-1000, it was found that the characteristic color image due to natural thermoluminescence was significantly observed on the Precambrian granite which was exposed with natural radiation alone since its formation. This simple and interesting technique, obtainable surface information reflecting impurities and local crystal defects in addition to small mineral constituents, was named as the thermoluminescence color imaging (abbreviated to TLCI) technique by the authors and its versatile applications were discussed.
D003116:Color; D005720:Gamma Rays; D008903:Minerals; D010781:Photography / Q000379:methods*; D013696:Temperature; D013819:Thermoluminescent Dosimetry / Q000379:methods*
D008903:Minerals