A constitutive model for layer development in shear zones near the brittle-ductile transition
Montesi, Laurent G. J.
MetadataShow full item record
The microstructure of ductile shear zones differs from that of surrounding wall rocks. In particular, compositional layering is a hallmark of shear zones. As layered rocks are weaker than their isotropic protolith when loaded in simple shear, layering may hold the key to explain localization of ductile deformation onto ductile shear zones. I propose here a constitutive model for layer development. A two-level mixing theory allows the strength of the aggregate to be estimated at intermediate degrees of layering. A probabilistic failure model is introduced to control how layers develop in a deforming aggregate. This model captures one of the initial mechanism of phase interconnection identified experimentally by Holyoke and Tullis (2006a, 2006b), fracturing of load bearing grains. This model reproduces the strength evolution of these experiments and can now be applied to tectonic modeling.
Author Posting. © American Geophysical Union, 2007. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 34 (2007): L08307, doi:10.1029/2007GL029250.
Showing items related by title, author, creator and subject.
Lithospheric shear velocity structure of South Island, New Zealand, from amphibious Rayleigh wave tomography Ball, Justin S.; Sheehan, Anne F.; Stachnik, Joshua C.; Lin, Fan-Chi; Yeck, William; Collins, John A. (John Wiley & Sons, 2016-05-23)We present a crust and mantle 3-D shear velocity model extending well offshore of New Zealand's South Island, imaging the lithosphere beneath the South Island as well as the Campbell and Challenger Plateaus. Our model is ...
Stern, Melvin E. (Woods Hole Oceanographic Institution, 1986-12)Our thanks go to Martin Landahl for his stimulating expository lectures on recent development in "lab scale" turbulent flow. This subject was covered by him and other staff members from the experimental, analytic, and ...
Ogden, Kelly A. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2017-02)Internal hydraulic jumps in flows with upstream shear are investigated numerically and theoretically. The role of upstream shear has not previously been thoroughly investigated, although it is important in many oceanographic ...