Elucidation of the genesis of extremely REY-rich mud based on independent component analysis

2016 Fiscal Year Final Research Report

• Project/Area Number: 15H06144
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Earth system and resources engineering
• Research Institution: The University of Tokyo
• Principal Investigator: Yasukawa Kazutaka 東京大学, 大学院工学系研究科(工学部), 助教 (00757742)
• Project Period (FY): 2015-08-28 – 2017-03-31
• Keywords: 海洋資源 / 地球化学 / 多変量解析 / 独立成分分析

Outline of Final Research Achievements

This study aims to elucidate the genesis of "extremely REY-rich mud" that is recently discovered within the Japanese Exclusive Economic Zone (EEZ) around Minamitorishima Island. In this study, I constructed a huge geochemical data set composed of major- and trace-element contents in bulk sediments collected from the Minamitorishima EEZ. The data set contains 1192 sediment samples, and 625 samples of them were newly analyzed by this study. Subsequently, I statistically analyzed the data matrix by using independent component analysis. As a result, I found that the multi-elemental data structure of the sediments in the Minamitorishima EEZ can be explained by five geochemical independent components. On the basis of the features of their downhole variations, it is implied that the extremely REY-rich mud is closely associated with an enhancement of a bottom water current.

Free Research Field

資源工学，地球化学