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Title: Constraints on the Nature of Terrestrial Core-Forming Melts: Ultra-High Pressure Transport Property Measurements and X-Ray Computed Tomography Final Report

Abstract

A key issue in models of planetary core formation is the interconnectness and potential percolation of iron-sulfide melts in contact with silicates at high temperature and pressure. To address this issue an integrated study of the electrical conductivity-texture-permeability relationships of olivine-sulfide partial-melt samples was performed. This work has application to the interpretation of high conductivity zones in the Earth as revealed by electromagnetic studies and to the origin and development of the Earth's core. The project consisted of three main tasks. (1) Synthesis and characterization of olivine-sulfide partial-melts. (2) Electrical conductivity measurements of the partial-melt and the individual melt and crystalline phases. (3) X-ray microtomographic determination of the 3-D structure and interconnectedness of the melt phase. The results are used to determine a model of permeability of a partially molten solid that incorporates the melt distribution, a goal that has never before been achieved. Material synthesis was accomplished in the piston cylinder apparatus and electrical conductivity measurements were performed at one atmosphere. X-ray computed tomography was performed on recovered samples at the ALS. This work makes use of and further enhances LLNL's strengths in high-pressure material properties, x-ray micro- and nanoscale imaging and development of transport theory.

Authors:
; ;
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
900154
Report Number(s):
UCRL-TR-218345
TRN: US200709%%557
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
58 GEOSCIENCES; COMPUTERIZED TOMOGRAPHY; DISTRIBUTION; ELECTRIC CONDUCTIVITY; ORIGIN; PERMEABILITY; PISTONS; SILICATES; SYNTHESIS; TRANSPORT; TRANSPORT THEORY

Citation Formats

Roberts, J J, Kinney, J H, and Ryerson, F J. Constraints on the Nature of Terrestrial Core-Forming Melts: Ultra-High Pressure Transport Property Measurements and X-Ray Computed Tomography Final Report. United States: N. p., 2006. Web. doi:10.2172/900154.
Roberts, J J, Kinney, J H, & Ryerson, F J. Constraints on the Nature of Terrestrial Core-Forming Melts: Ultra-High Pressure Transport Property Measurements and X-Ray Computed Tomography Final Report. United States. doi:10.2172/900154.
Roberts, J J, Kinney, J H, and Ryerson, F J. Fri . "Constraints on the Nature of Terrestrial Core-Forming Melts: Ultra-High Pressure Transport Property Measurements and X-Ray Computed Tomography Final Report". United States. doi:10.2172/900154. https://www.osti.gov/servlets/purl/900154.
@article{osti_900154,
title = {Constraints on the Nature of Terrestrial Core-Forming Melts: Ultra-High Pressure Transport Property Measurements and X-Ray Computed Tomography Final Report},
author = {Roberts, J J and Kinney, J H and Ryerson, F J},
abstractNote = {A key issue in models of planetary core formation is the interconnectness and potential percolation of iron-sulfide melts in contact with silicates at high temperature and pressure. To address this issue an integrated study of the electrical conductivity-texture-permeability relationships of olivine-sulfide partial-melt samples was performed. This work has application to the interpretation of high conductivity zones in the Earth as revealed by electromagnetic studies and to the origin and development of the Earth's core. The project consisted of three main tasks. (1) Synthesis and characterization of olivine-sulfide partial-melts. (2) Electrical conductivity measurements of the partial-melt and the individual melt and crystalline phases. (3) X-ray microtomographic determination of the 3-D structure and interconnectedness of the melt phase. The results are used to determine a model of permeability of a partially molten solid that incorporates the melt distribution, a goal that has never before been achieved. Material synthesis was accomplished in the piston cylinder apparatus and electrical conductivity measurements were performed at one atmosphere. X-ray computed tomography was performed on recovered samples at the ALS. This work makes use of and further enhances LLNL's strengths in high-pressure material properties, x-ray micro- and nanoscale imaging and development of transport theory.},
doi = {10.2172/900154},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Jan 20 00:00:00 EST 2006},
month = {Fri Jan 20 00:00:00 EST 2006}
}

Technical Report:

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