• Skip to main content
  • Accessibility information
Contact us
  • Accessibility
  • Staff
  • Students
The University of Northampton

The University of Northampton

Site tools

  • Advanced Search
  • Site Map
Search

Site Navigation

  • Home
  • About us
  • Study
  • Research
  • Social enterprise
  • Business & community
  • Alumni
  • Login
  • NECTAR Home
  • NECTAR FAQs
  • Browse Publications
  • Advanced Search
  • JISC Project
  • Contact
  • Help with NECTAR

Micro segregation rates of liquid Fe-Ni-S metal in natural silicate-metal systems: A combined experimental and numerical study

Tools
- Tools
+ Tools

Rushmer, T. and Petford, N. (2011) Micro segregation rates of liquid Fe-Ni-S metal in natural silicate-metal systems: A combined experimental and numerical study. Geochemistry, Geophysics, Geosystems. 12(3) 1525-2027.
  • Documents
  • Secured
  • Information
[img]
Untitled (3225Kb)
[img]
Untitled (49Kb)
Creators:Rushmer, T. and Petford, N.
Abstract:
We present results of an image‐based numerical model aimed at quantifying the microsegregation and
flow of liquid metal in meteorites prior to the onset of silicate melting. The sample material is the H6 chondrite
Kernouvé. The model utilizes the observed geometry of two distinct chondrite textures associated with
grain‐scale melt segregation in the following: (1) the undeformed (natural) state and (2) during deformation
and partial melting under controlled (laboratory) conditions. The numerical simulations recover liquid
metal segregation rates of ∼10−6 to 10−4 m s−1 for matrix permeabilities (k) of 10−12 < k < 10−10 m2
and pressure gradients of ∼1 and 104 Pa m−1. The velocity flow field is position‐dependent across the
sample, reflecting initial grain‐scale heterogeneity and anisotropy in the spatial distribution of metal prior
to melting. In addition to porous flow, we use a coupled Brinkman‐Navier‐Stokes solution to quantify
liquid metal segregation through deformation‐induced microscale veins. Melt flow velocities in veins are
several orders faster than matrix flow, implying that a combination of porous (grain‐scale) flow feeding
into a network of small‐scale cracks and veins during the initial stages of partial melting may be an extremely efficient mechanism for segregating liquid metal from silicate matrix in planetesimals undergoing deformation. This mechanism may be temporary and confined only to the earliest stages of melt microsegregation because with increasing temperature, the onset of silicate melting shuts off liquid metal segregation by creeping matrix flow. The point at which this occurs marks an important transition in the mode and style of internal differentiation.
Official URL:http://www.agu.org/pubs/crossref/2011/2010GC003413...
Item Type:Article
Uncontrolled Keywords:Core formation, Planetesimal, experiment, numerical simulations, partial melting
Subjects:Q Science > QE Geology > QE500 Dynamic and structural geology > QE515 Geochemistry
Schools and Departments:University Departments > Directorate
DOI:10.1029/2010GC003413
Date:2011
Repository Staff Only: item control page
Top

Main switchboard

01604 735500

Course enquiries

0800 358 2232

study@northampton.ac.uk

  • Accessibility statement
  • Terms and conditions

Follow us

Follow us on twitter Follow us on youtube Follow us on flickr Follow us on facebook

Find us

Avenue Campus
Map of Avenue Campus
Park Campus
Map of Park Campus

Copyright © 2010 The University of Northampton