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Characteristics of ESR signals and TLCLs of quartz included in various source rocks and sediments in Japan: A clue to sediment provenance

Shimada A., Takada M., Toyoda S.

Geochronometria

2013

Vol. 40, no. 4

334--340

The variation of electron spin resonance (ESR) signal intensities and thermoluminescence colour images (TLCIs) of quartz was investigated in the present study for various rocks and sediments in Japan, to discuss the possibilities of identifying the sediment provenance. The ESR signal intensity of the E1' centre in the same grain size in granitic quartz varies from sample to sample, except for that in Quaternary samples of volcanic sediment, which is very low, close to the noise level. It was found that the diagram, ESR intensities of Al versus Ti-Li centre signal intensities, distinguish volcanic from the same grain size in granitic quartz as well as distinguish individual tephra from another. The TLCIs from volcanic quartz and some granitic quartz samples is almost red and that from the rest of granitic and metamudstone quartz is blue as results of TLCIs although the emission intensities are dif-ferent. Our results suggest that examining the multiple-centre signal intensities of ESR and the TLCIs are ef-fective to identify the source of quartz and to estimate the sediment provenance.

ESR dating of sedimentary quartz from two pleistocene deposits using Al and Ti-centers

Tissoux H., Toyoda S., Falgueres C., Voinchet P., Takada M., Bahain J-J., Despriée J.

Geochronometria

2008

Vol. 30

23-31

One sample from a fluvial terrace of Loir river (France) deposited during isotopic stages 7-8 and two samples from isotopic stage 5 marine sediments of Echizen Coast (Japan) were dated by ESR of quartz grains. Both additive and regenerative techniques were used on Ti-Li and Ti-H centers of quartz. No change of sensitivity of the centers was observed during regeneration which significantly reduced the errors on the equivalent doses. Bleaching experiments indicated that the Ti-Li center is less sensitive to UV(ultra-violet)-A (365-412 nm) than to the full sun spectrum whereas UVA alone is sufficient to reset the bleachable component of the Al-center. This effect could be the origin of the strong overestimation of the ages determined using the Ti-Li center in this study. The comparison of the equivalent doses determined by the two Ti-centers indicated that bleaching before deposition of the fluvial sediment was apparently better than for the marine sample.