Stress-driven melt segregation in partially molten olivine-rich rocks deformed in torsion

Research output: Contribution to journalArticlepeer-review

56 Scopus citations

Abstract

Torsion experiments on partially molten aggregates of olivine + chromite + 4 vol. % mid-ocean ridge basalt provide new insights into the interactions between deformation and melt segregation. When samples are sheared, melt segregates into distinct melt-rich bands oriented ~20° antithetic to the macroscopic shear plane. In one series of experiments, samples were deformed at similar shear strain rates (or stresses) to a range of finite shear strains to explore the evolution of melt-rich bands. In another series of experiments, samples were deformed to similar finite shear strains at a range of strain rates to explore the effect of strain rate (or stress) on band spacing and microstructure. We relate variations in strain rate to the compaction length and show that band spacing increases with increasing compaction length.These experiments provide new information on the evolution of melt distribution, the partitioning and localization of strain, and the scaling of experimental results to the Earth's mantle.

Original languageEnglish (US)
Article numberegp062
Pages (from-to)21-42
Number of pages22
JournalJournal of Petrology
Volume51
Issue number1-2
DOIs
StatePublished - Sep 15 2009

Bibliographical note

Funding Information:
We are grateful to Ben Holtzman for helpful discussion and providing much assistance developing routines for quantifying the melt distribution. We thank Julian Mecklenburgh, Richard Katz, and Jean Louis Vigneresse for thoughtful reviews that helped improve this paper. This work was supported by NSF OCE 0648020.

Keywords

  • Melt segregation
  • Melt-rich bands
  • Partially molten rocks
  • Torsional deformation

Fingerprint Dive into the research topics of 'Stress-driven melt segregation in partially molten olivine-rich rocks deformed in torsion'. Together they form a unique fingerprint.

Cite this