*Aiko SHIMADA1, Shin TOYODA2, Masashi TAKADA1
(1.Application Support Team, JEOL RESONANCE Inc., 2.Department of Applied Physics, Okayama University of Science)
Keywords:Electron Spin Resonance, Sediments provenance, Quartz, Sediments, Thermoluminescence, River bed sediments
The sediment provenance would give important information on the erosion processes, uplift of the mountains and so on, suggesting the environments at the time of sediment transportation. The sediment is made of fine grains such as sand and silt. When a new procedure for clarifying provenance of such sediments is established, it will be useful to elucidate the provenance of sediments in the geohistorical environments, which may occasionally be related to stream piracy, regional tectonic setting and/or the environment changes of the hinterland.There have been already some Electron Spin Resonance (ESR) and luminescence studies on sediment provenance. The intensity of the E1' center in quartz is shown to be a useful parameter to investigate the provenance of aeolian dust as well as of sediments [1][2]. The crystallinity index (CI) in combination with ESR is employed to discriminate two different sources of eolian dust in the sediment core taken from the Japan Sea [3]. Quartz of four distinct origins can be distinguished using impurity (Al, Ti-Li, Ti-H, Ge) centers observed after beta irradiation [4]. Shimada and Takada (2008) and Shimada et al. (2013) also show that the Al, Ti-Li and E1' center signal intensities from the natural quartz are useful to distinguish the sediment provenance [5][6]. Volcanic quartz is reported to emit stronger red thermoluminescence (TL) than blue one whereas plutonic quartz does vice versa [7]. Quartz of eolian origin transported from China can be distinguished from volcanic quartz originated in Japanese tephra by looking at TL color of quartz grains [8]. In this study, we report the characteristics of ESR and TL of quartz taken from present river bed sediments, to discuss the possibilities of identifying sediment provenance. [1] Naruse T, Ono Y, Hirakawa K, Okashita M, and Ikeya M, 1997. Source areas of eolian dust quartz in East Asia: a tentative reconstruction of prevailing winds in isotope stage 2 using electron spin resonance. Geographical review of Japan 70A-1, 15?27.[2] Toyoda S and Naruse T, 2002. Eolian Dust from Asia Deserts to Japanese Island since the last Glacial Maximum: the Basis for the ESR Method, Japan Geomorphological union 23-5, 811-820.[3] Nagashima K,Tada R, Tani A, Toyoda S, Sun Y, and Isozaki Y, 2007. Contribution of aeolian dust in Japan Sea sediments estimated from ESR signal intensity and crystallinity of quartz. Geochemistry, Geophysics, Geosystems, doi:10. 1029/2006GC001364.[4] Duttinea M, Villeneuvea G, Bechtela F, Demazeaub G, 2002. Caracterisation par resonance paramagnetique electronique (RPE) de quartz naturels issus de differentes sources. C.R.Geoscience 334, 949?955.[5] Shimada A and Takada M, 2008. Characteristics of Electron Spin Resonance (ESR) signals in quartz from igneous rock samples: a clue to sediment provenance. Annual Reports of Graduate School of Humanities and Sciences, 23, 187-195.[6] Shimada A, Takada M and Toyoda S, 2013. Characteristics of ESR signals and TLCLs of quartz included in various source rocks and sediments in Japan: A clue to sediment provenance. Geochronometria, 40, Issue 4, 334-340.[7] Hashimoto T, Koyanagi A, Yokosaka K, Hayashi Y and Sotobayashi T, 1986. Themoluminecence color images from quartz of beach sands. Geochemical journal 20,111-118.[8] Ganzawa Y, Watanabe Y, Osanai F and Hashimoto T, 1997. TL color images from quartzes of loess and tephra in China and Japan, Radiation Measurements 27, 383-388.