Deformation of Polyphase Aggregates
I am interested in the deformation of polyphase aggregates, and the strain partitioning that can occur. My group has attempted to relate the bulk deformation behavior of "granites" and "gabbros" to the properties, volume proportions, and geometric arrangement of their constituent phases, in experiments taken to high strain.
For finegrained granites we have documented a change in the stresssupporting matrix phase with progressive strain, and for fine-grained gneisses we have shown how the development and maintenance of a localized ductile shear zone depends on the strength contrasts between the constituent phases.
Tullis, J., and Yund, R.A., 1977, Experimental deformation of dry Westerly granite: J. Geophys. Res., 82, 57055718.
Dell'Angelo, L.N., Tullis, J. and Yund, R.A., 1987, Transition from dislocation creep to melt-enhanced diffusion creep in fine-grained granitic aggregates: Tectonophysics, 139, 325-332.
Dell'Angelo, L.N. and Tullis, J.,1988, An experimental study of the effect of partial melt on granitic aggregates deformed at high pressures and temperatures: Jour. Met. Geol., 6, 495-516.
Tullis, J., Dell'Angelo, L.N. and Yund, R.A., 1990, Ductile shear zones from brittle precursors in feldspathic rocks; the possible role of dynamic recrystallization: AGU Geophysical Monograph, 56, 6782.
Tullis, T.E., Horowitz, F., and Tullis, J., 1991, Flow laws of polyphase aggregates from end member flow laws: J. Geophys. Res., 96, 80818096.
Tullis, J. and Wenk, H.R., 1994, The effect of muscovite on the strength and lattice preferred orientations of experimentally deformed quartz aggregates: in Wenk, H.R. (ed.) Polyphase Polycrystal Plasticity, Mater. Sci. Engin., A175, 209-220.
Dell'Angelo, L. and Tullis, J., 1996, Textural and mechanical evolution with progressive strain in experimentally deformed aplite. Tectonophysics, 256, 57-82.
Holyoke, C. and Tullis, J., 2005, Formation and maintenance of ductile shear zones. Geology, 34, 105-108.
Holyoke, C. and Tullis, J., 2006, Mechanisms of weak phase interconnection and effects of phase strength contrast on fabric development. J. Struc. Geol., 28, 621-640.
Brown faculty collaborators:
Other project collaborators:
See above publications list.
Back to Jan Tullis's Brown Research Profile