Precise correlation between Lake Suigetsu and the Sea of Japan: towards understanding of mechanisms of D-O events.

2017 Fiscal Year Final Research Report

• Project/Area Number: 15H02143
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Stratigraphy/Paleontology
• Research Institution: Ritsumeikan University
• Principal Investigator: Nakagawa Takeshi 立命館大学, 総合科学技術研究機構, 教授 (20332190)
• Co-Investigator(Kenkyū-buntansha): 池原 研 国立研究開発法人産業技術総合研究所, 地質情報研究部門, 首席研究員 (40356423) ; 佐川 拓也 金沢大学, 自然システム学系, 助教 (40448395)
• Research Collaborator: Smith Victoria オックスフォード大学, 考古学教室, 准教授 ; Albert Paul オックスフォード大学, 考古学教室, 研究員 ; NAGAHASHI Yoshitaka 福島大学, 強制システム理工学類, 教授 ; KIMURA Jun-ichi 海洋研究開発機構, 地球内部物質循環研究分野, 上席技術研究員
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 気候変動 / 水月湖 / 日本海 / 高精度対比 / 火山灰

Outline of Final Research Achievements

A newly obtained sediment core from Wakasa Bay, the Sea of Japan (WB) and the annually laminated SG06 core from Lake Suigetsu were analysed for tephra layers and radiocarbon dates, in an attempt to establish precise correlate between those cores. The WB6 core was then analysed for TOC, surface reflectance and foraminifera chemistry. The SG06 core was analysed for pollen and cryptotephra chemistry.
Reconstructed marine and terrestrial environments exhibited millennial-scale oscillations that are most likely counterparts of D-O events in Greenland. However, the amplitude of the oscillations in the terrestrial environment was much attenuated. The coldest phase of the last glacial was limited to ca. 17-20 ka, which does not correspond to both timing and duration of the minima at the Greenland.

Free Research Field

古気候学、地質年代学