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Luminescence dating observes the natural accumulated radiation damage caused by radioisotopes such as U and Th as the form of glow after stimulation by heating or lightening.The luminescence is observed at various wavelength bands and their characteristics have been studied mainly on quartz and feldspar.The emission color of luminescence can be recorded easily by using thermoluminescence color image(TLCI) analysis method for samples artificially irradiated with gamma-rays.Inagaki et al(2009) investigated the validity of TLCI analysis for boring core samples from Lake Baikal(in Russia),Lake Khuvsgul(in Mongolia) and Byeokgolje(in South Korea).When TLCI analysis is applied to polymineral from lake sediments,the luminous mineral compositions of samples reflect of the regional characteristic and climate of the studied area.If we combine the TLCI with other data,we would be able to obtain information of sample’s source and the surrounding environment at the time of deposition.In this study,HDP04 core sample from Lake Hovsgol was investigated to see color change of glow along depth.Then the acquired TLCI fluctuation was compared with the data investigated by previous studies.All samples were etched with H_2O_2 to remove organic matter that does not show any luminescence.A ~(60)Co gamma-ray source was used to irradiate samples at Kyoto University Research Reactor Institute.Afterward the photograph of TLCI was taken under a constant temperature of 230 ℃.The used camera was normal single-lens reflex camera(Canon EOS Kiss Digital N) with micro lens(Canon EF 50 mm f/2.5 Compact-Macro).To analyze TLCI quantitatively,colored pixels of the photograph were picked up by the program built in this study and then converted to numerical values.Based on Ganzawa et al(2001),color index was calculated from these numerical values and then were divided into five color ranges.TLCIs from an aliquot vary and show poor reproductivity,however,the average results varied along depth reflecting characteristics of sediment accumulation at that time.The correlations between the TLCI and data from other analysis(physical analysis,age determination,etc.) will be discussed to understand what is responsible to the change in TLCI.
Luminescence dating observes the natural accumulated radiation damage caused by radioisotopes such as U and Th as the form of glow after stimulation by heating or lightening. The luminescence is observed at various wavelength bands and their characteristics have been studied primarily on quartz and feldspar. Emission color of luminescence can be recorded easily by using thermoluminescence color image (TLCI) analysis method for samples artificially irradiated with gamma-rays. Inagaki et al (2009) investigated the validity of TLCI analysis for boring core samples from Lake Baikal (in Russia), Lake Khuvsgul (in Mongolia) and Byeokgolje (in South Korea) .When TLCI analysis is applied to polymineral from lake sediments, the luminous mineral compositions of samples reflect of the regional characteristic and climate of the studied area. If we combine the TLCI with other data, we would be able to obtain information of sample’s source and the surrounding environment at the time of deposition. In this study, HDP04 core sample from Lake Hovsgol was investigated to see color change of glow along depth. Twent the acquired TLCI fluctuation was compared with the data investigated by previous studies. All samples were etched with H_2O_2 to remove organic matter that does not show any luminescence. A (60) Co gamma-ray source was used to irradiate samples at Kyoto University Research Reactor Institute. Afterward the photograph of TLCI was taken under a constant temperature of 230 ° C. The used camera was normal single-lens reflex camera (Canon EOS Kiss Digital N) with micro lens (Canon EF 50 mm f / 2.5 Compact-Macro). Analysis of TLCI quantitatively, colored pixels of the photograph were picked up by the program built in this study and then converted to numerical values. Based on Ganzawa et al (2001), color index was calculated from these numerical values and then were divided into five color ranges.TLCIs from an aliquot vary and show poor reproductivity, however, the average results varied along depth reflecting c haracteristics of sediment accumulation at that time. correlations between the TLCI and data from other analysis (physical analysis, age determination, etc.) will be discussed to understand what is responsible to the change in TLCI.