Home | Contact Us | Sitemap | 中文 | CAS | Director's Email
Location:Home > Papers > Recent Papers
Electrical conductivity of anhydrous and hydrous gabbroic melt under high temperature and high pressure: implications for the high-conductivity anomalies in the mid-ocean ridge region TEXT SIZE: A A A

The electrical conductivity of gabbroic melt with four different water contents (i.e., 0 %, 2.59 wt %, 5.92 wt %, and 8.32 wt %) was measured at temperatures of 873-1373K and pressures of 1.0-3.0 GPa using a YJ-3000t multi-anvil high-pressure apparatus and Solartron-1260 impedance spectroscopy analyzer. At a fixed water content of 2.59 wt %, the electrical conductivity of the sample slightly decreased with increasing pressure in the temperature range of 873-1373 K, and its corresponding activation energy and activation volume were determined as 0.87 +/- 0.04 eV and 1.98 +/- 0.02 cm(3) molec(-1), respectively. Under the certain conditions of 873-1373K and 1.0 GPa, the electrical conductivity of the gabbroic melts tends to gradually increase with a rise in water content from 0 wt% to 8.32 wt %, and the activation enthalpy decreases from 0.93 to 0.63 eV accordingly. Furthermore, functional relation models for the electrical conductivity of gabbroic melts with variations of temperature, pressure, and water content were constructed at high-temperature and high-pressure conditions. In addition, the dependence relation of the electrical conductivity of melts with the degree of depolymerization was explored under conditions of four different water contents at 1373K and 1.0 GPa, and three previously available reported results on those of representative calc-alkaline igneous rock melts (i.e., dacitic melt, basaltic melt, and andesitic melt) were compared in detail. In combination with our presently acquired electrical conductivity data on gabbroic melt with four different water contents and the available data on polycrystalline olivine, the electrical conductivity of a gabbroic melt-olivine system with variation of the volume percentage of anhydrous and hydrous melts was successfully constructed by using the typical Hashin-Shtrikman upper-bound model. In light of the electrical conductivity of the gabbroic melt-olivine system with previous magnetotelluric (MT) results, we find that anhydrous and hydrous gabbroic melts can be employed to reasonably interpret the high-conductivity anomalies in the Mohns Ridge of the Arctic Ocean.

Publication name

 Solid Earth, Volume 14, Issue 8, Page 847-858, DOI 10.5194/se-14-847-2023, Article Number 136139, Published AUG 15 2023


 Wang, Mengqi; Dai, Lidong; Hu, Haiying; Hu, Ziming; Jing, Chenxin; Yin, Chuanyu; Luo, Song; Lai, Jinhua

Corresponding author(s) 

 Dai, Lidong; Hu, Haiying
 dailidong@vip.gyig.ac.cn; huhaiying@vip.gyig.ac.cn
 Chinese Acad Sci, Inst Geochem, Key Lab High Temp & High Pressure Study Earth Inte, Guiyang, Peoples R China

Author(s) from IGCAS   Dai, Lidong; Hu, Haiying; Wang, Mengqi; Hu, Ziming; Jing, Chenxin; Yin, Chuanyu; Luo, Song; Lai, Jinhua

View here for the details 

Copyright © Institute Of Geochemistry, Chinese Academy of Sciences All Rights Reserved.
Address: 99 West Lincheng Road, Guanshanhu District, Guiyang, Guizhou Province 550081, P.R.China
Tel: +86-851-85895239 Fax: +86-851-85895239 Email: web_en@mail.gyig.ac.cn