Electromagnetic evidence for volatile-rich upwelling beneath the society hotspot, French Polynesia

Type Article
Date 2016-12
Language English
Author(s) Tada Noriko1, Tarits Pascal2, Baba KiyoshiORCID3, Utada HisashiORCID3, Kasaya Takafumi1, Suetsugu Daisuke1
Affiliation(s) 1 : Japan Agcy Marine Earth Sci & Technol, Yokosuka, Kanagawa, Japan.
2 : Inst Univ Europeen Mer, UMR Domaines Ocean, Plouzane, France.
3 : Univ Tokyo, Earthquake Res Inst, Tokyo, Japan.
Source Geophysical Research Letters (0094-8276) (Amer Geophysical Union), 2016-12 , Vol. 43 , N. 23 , P. 12021-12026
DOI 10.1002/2016GL071331
WOS© Times Cited 6
Keyword(s) hotspot, marine magnetotellurics, three-dimensional inversion, volatiles, partial melt
Abstract

We have conducted a seafloor magnetotelluric survey that images, for the first time, three-dimensional electrical conductivity structure in the upper mantle beneath the Society hotspot. A striking feature in our model is a high-conductivity anomaly a few hundred kilometers in diameter, which is continuous from the lowest part of the upper mantle to a depth of approximately 50km below sea level. Using theoretical and experimental results from mineral physics, we interpret the high-conductivity anomaly as evidence of the melt fraction up to 2.2vol.%, which is robust regardless of assumed temperature, and the existence of carbonated silicate melt beneath the hotspot. Our results suggest that the Society hotspot is a pathway for ascending volatiles from the deeper part of the upper mantle to the surface.

Full Text
File Pages Size Access
Publisher's official version 6 2 MB Open access
Supporting Information S1 11 1 MB Open access
Top of the page

How to cite 

Tada Noriko, Tarits Pascal, Baba Kiyoshi, Utada Hisashi, Kasaya Takafumi, Suetsugu Daisuke (2016). Electromagnetic evidence for volatile-rich upwelling beneath the society hotspot, French Polynesia. Geophysical Research Letters, 43(23), 12021-12026. Publisher's official version : https://doi.org/10.1002/2016GL071331 , Open Access version : https://archimer.ifremer.fr/doc/00638/75054/