| Project/Area Number |
16300296
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Geography
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| Research Institution | Nara Women's University |
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Principal Investigator |
TAKADA Masashi Nara Women's University, Faculty of Letters, Associate Professor, 文学部, 助教授 (60273827)
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| Co-Investigator(Kenkyū-buntansha) |
MAEMOKU Hideaki Hiroshima University, Graduate School of Education, Associate Professor, 大学院・教育学研究科, 助教授 (50222287)
YOKOYAMA Yusuke The University of Tokyo, Department of Earth and Planetary Sciences, Lecturer, 大学院・理学研究科, 講師 (10359648)
三浦 英樹 (三浦 秀樹) 国立極地研究所, 助手 (10271496)
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| Project Period (FY) |
2004 – 2006
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| Project Status |
Completed (Fiscal Year 2006)
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| Budget Amount *help |
¥7,200,000 (Direct Cost: ¥7,200,000)
Fiscal Year 2006: ¥1,700,000 (Direct Cost: ¥1,700,000)
Fiscal Year 2005: ¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 2004: ¥3,500,000 (Direct Cost: ¥3,500,000)
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| Keywords | East Antarctica / Quaternary sediments / ^<14>C ages / ice sheet / OSL dating / ESR dating / conmogenic dating / 氷床変遷史 / 光ルミネッセンス年代 |
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| Research Abstract |
We have been studied the stratigraphic relationship between raised beach deposits including in-situ fossil shells and glacial deposits in the Lutzow-Holm Bay region, East Antarctica, to clarify that the Antarctic ice sheet, unlike the northern hemisphere ice sheet, was not the greatest during the marine isotope stage (MIS) 2 but the greatest at the age older than 46 ka. The 46 ka is, however, close to the limit of 14C analysis and sensitive to the effect of contamination. Therefore, ages obtained by other dating methods would be of great help in interpreting those data. For this reason we investigate on optically stimulated luminescence (OSL), electron spin reasonance (ESR) and cosmogenic dates of Quaternary sediments in the Lutzow-Holm Bay region, East Antarctica, to compare them with AMS 14C dates and to discuss on late Pleistocene chronology.
Though some OSL or cosmogenic ages from our samples dearly differ from 14C ages, most of OSL, 14C, and cosmogenic dates seem to be consistent if we take calibration factors such as reservoir correction into account. While we should make further sophisticated dating experiments, we can reconfirm that the East Antarctic Ice Sheet did not re-advance to the ice-free area on the northernmost part of the Soya Coast during the LGM. There is a possibility that the ice sheet retreated from the area during the period prior to about 50,000 or 80,000 yrBP.
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