Assessment of beryllium-10 in offshore sediments for reconstructing environmental change in East Africa

2019 Fiscal Year Final Research Report

• Project/Area Number: 18K18178
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 63010:Environmental dynamic analysis-related
• Research Institution: Nagoya University
• Principal Investigator: Yamane Masako 名古屋大学, 宇宙地球環境研究所, 特任助教 (30785928)
• Project Period (FY): 2018-04-01 – 2020-03-31
• Keywords: ベリリウム10 / 海洋堆積物 / 東アフリカ / 陸域環境変動 / 鮮新世 / 更新世 / 完新世 / 国際深海科学掘削計画

Outline of Final Research Achievements

To assess the usability of beryllium-10 contained in the coastal marine sediments as a proxy of environmental changes on land, beryllium-10 in the marine sediments collected from various sedimentary environment were analyzed. Ratio of the beryllium-10 brought from the land contained in the beryllium-10 of the coastal marine sediments is 70 % or more. The beryllium-10 variation during past 4 million years recorded in the coastal marine sediment, obtained from offshore of the East Africa, shows a long-term variation that is synchronized with the vegetation change in East Africa. There is a possibility that the beryllium-10 variation of coastal marine sediments reflects the environmental changes of land.

Free Research Field

古気候学

Academic Significance and Societal Importance of the Research Achievements

東アフリカは乾燥地域であり、過去数百万年間の連続的な気候・環境変動の復元は非常に困難である。本研究により、連続性に優れたアーカイブである海洋堆積物のベリリウム10から陸域の気候・環境変動を復元できる可能性が示された。これにより、東アフリカの過去数百万年間にわたる連続的な気候・環境変動が復元され、東アフリカ地域の気候・環境変動と人類進化との関係の議論に進展をもたらすと期待される。