Reconstruction of sea-level change since the Last Glacial Maximum based on tectonically subsided, incised-valley fills

2017 Fiscal Year Final Research Report

• Project/Area Number: 26282079
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Geography
• Research Institution: Nagoya University
• Principal Investigator: Hori Kazuaki 名古屋大学, 環境学研究科, 准教授 (70373074)
• Co-Investigator(Kenkyū-buntansha): 田邉 晋 国立研究開発法人産業技術総合研究所, 地質調査総合センター, 主任研究員 (50415709) ; 納谷 友規 国立研究開発法人産業技術総合研究所, 地質調査総合センター, 主任研究員 (90549891)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Keywords: 海水準変動 / 沖積層 / 最終氷期 / 沈降域 / 嘉南平野 / 台湾

Outline of Final Research Achievements

This study investigated relative sea-level change since the Last Glacial Maximum (LGM) based on the analysis of incised-valley fills at the Tsengwen River, western Taiwan. The thickness of incised-valley fill deposits is approximately 180 to 200 m and its succession consists of upward-fining and upward-coarsening in ascending order. Radiocarbon ages obtained from the base of the deposits are around the LGM. Sediment accumulation rate was almost equal to the rate of eustatic sea-level rise. Accumulation of the deposits was recognized since around the LGM. The accumulation from the LGM to 17500 cal BP may have resulted from accommodation due to tectonic subsidence of the basin as well as glacio-eustatic sea-level rise. In addition, it was estimated that the rate of glacio-eustatic sea level rise increased since 15000 cal BP.

Free Research Field

地理学