Investigation of mantle electrical conductivity beneath the Tristan da Cunha hotspot in Atlantic Ocean by Japan-Germany collaboration

2014 Fiscal Year Final Research Report

• Project/Area Number: 23403005
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 海外学術
• Research Field: Solid earth and planetary physics
• Research Institution: The University of Tokyo
• Principal Investigator: KIYOSHI Baba 東京大学, 地震研究所, 助教 (70371721)
• Co-Investigator(Renkei-kenkyūsha): UTADA Hisashi 東京大学, 地震研究所, 教授 (70134632)
• Research Collaborator: JEGEN-KULCSAR Marion キール大学, 海洋研究所(IFM-GEOMAR)
• Project Period (FY): 2011-04-01 – 2015-03-31
• Keywords: マントル / ホットスポット / トリスタン・ダ・クーニャ / 大陸分裂 / 電気伝導度 / MT法 / 海底電位磁力計 / 国際研究者交流

Outline of Final Research Achievements

This research project aims to investigate the electrical structure of the mantle beneath the Tristan da Cunha hotspot in southern Atlantic Ocean to deepen the knowledge of the hotspot source. This is a collaborative study between Japanese and German research groups. The seafloor electromagnetic observation was conducted for an year from January 2012 by using total 26 ocean bottom electromagnetometers. The time variation of the natural electromagnetic field was measured and analyzed to obtain electromagnetic response functions which have information of Earth's electrical conductivity. The quality of observed data were good for most of the stations. Further inversion analysis of the response functions will enable us to image a three-dimensional electrical conductivity structure beneath the observation area.

Free Research Field

海底電磁気学