Project/Area Number |
25800282
|
Research Category |
Grant-in-Aid for Young Scientists (B)
|
Allocation Type | Multi-year Fund |
Research Field |
Geology
|
Research Institution | Museum of Natural and Environmental History, Shizuoka (2015) Shizuoka University (2014) Waseda University (2013) |
Principal Investigator |
YAMADA Kazuyoshi ふじのくに地球環境史ミュージアム, 学芸課, 准教授 (60508167)
|
Project Period (FY) |
2013-04-01 – 2016-03-31
|
Project Status |
Completed (Fiscal Year 2015)
|
Budget Amount *help |
¥4,030,000 (Direct Cost: ¥3,100,000、Indirect Cost: ¥930,000)
Fiscal Year 2015: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000)
Fiscal Year 2014: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000)
Fiscal Year 2013: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
|
Keywords | 湖沼堆積物 / 古気候 / 年縞 / 一ノ目潟 / アジアモンスーン / 晩氷期 |
Outline of Final Research Achievements |
Thirty-seven meter long sediment cores were recovered from Lake Ichi-no-Megata, northeast Japan. Six lithozones were classified based on detailed lithology and physical properties of the sediment cores. Most of the sediment sequences were thinly laminated except one interval from 26.3 to 31.7 m, which is composed of volcanic materials of an adjacent maar, Lake San-no-Megata. Although these laminations had different structures and composition between the Holocene and the last glacial period, they have been related to an annual cycle of deposition, i.e. a varve. Multiple AMS 14C dates enabled us to establish the detailed chronology agreed well with tephrostratigraphy over the last 30,000 years. The age-depth plots indicate a stable deposition environment with a linear sedimentation rate (0.727 mm/year) since after 25,000 cal BP. The continuous laminated sediments have great potential for high-resolution study of the past environmental changes since the last glacial period.
|