2015 Fiscal Year Final Research Report
Reconstruction of annual-scale paleoclimatic changes during the mid-Cretaceous evidenced from Mongolian lacustrine record
| Project/Area Number |
25870309
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| Research Category |
Grant-in-Aid for Young Scientists (B)
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| Allocation Type | Multi-year Fund |
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| Research Field |
Geology
Stratigraphy/Paleontology
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| Research Institution | Nagoya University |
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Principal Investigator |
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| Project Period (FY) |
2013-04-01 – 2016-03-31
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| Keywords | 白亜紀 / 温室期 / 湖成層 / 年縞 / 年スケール / 地球軌道要素 / 気候変動 |
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| Outline of Final Research Achievements |
In order to reconstruct annual- to orbital-scale paleoclimatic changes, I examined Aptian lacustrine record (Shinekhudag Formation) in southeast Mongolia. Based on the radiometric age dating and detail chronostratigraphic study, the Shinekhudag Formation is considered to be deposited between ca. 122-119 Ma. Based on the analysis of major and minor elemental compositions, three paleoclimatic proxies (precipitation, weathering, lake bottom redox state) have beed identified. Changes of each paleoclimatic proxies are thought to be reflected to the differenct orbital parameters. The micrometer-scale laminations, consisting of couplets of algal organic matter and detrital minerals, are most likely varves, reflecting seasonal cyclicity. Thus, the Shinekhudag Formation are thought to record the annual- to orbital-scale climatic change in mid-latitude Asia during the Aptian time.
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| Free Research Field |
古気候学
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