Dating of marine terrace sediments by ESR, TL and OSL methods and their applicabilities

We present the results of a pilot study in which ESR, TL and optical dating are intercompared to assess their suitabilities for application to measurement of the uplift rates of the Japanese Islands. Samples used were known-age marine terrace sediments collected from three sites in Central Japan. As a result of optical bleaching experiments, it was found that the TL residual intensity was identified by UV lamp, but we were not able to determine how the bleaching of the ESR Ti signal proceeded in antiquity. ESR, TL and optical dating were performed using the Ti signal, the red TL emission and the UV emissions measured during stimulation by the waveband 500+/-40 nm respectively. Equivalent doses were estimated using the additive-dose method. Dose rates were calculated from radioisotope concentrations measured using neutron activation analysis. It was found that variation in pore water content over time was of major significance in ape determinations for these sediments, on account of their history of deposition underwater, with subsequent uplift and drainage. It was concluded from the correspondence of ages estimated by TL and optical dating with geological expectation that the TL and optical dating methods are suitable for dating marine terrace sediments. (C) 1997 Elsevier Science Ltd.