experimental rock deformation; rheology; seismic anisotropy; partial melting; Metapelites
Almqvist B.S.G. Misra S. Mainprice D. (2015), Melt production and percolation in synthetic quartz-mica schist: in situ detection via ultrasonic velocity drops and anisotropy reduction, in Earth and Planetary Science Letters
, 425, 24-33.
Almqvist B.S.G. Biedermann A.R. Klonowska I. Misra S. (2015), Petrofrabric development during experimental partial melting and recrystallization of a mica-schist analogue., in Geochemistry, Geophysics, Geosystems
, 16(10), 3472-3483.
Misra S. Burg J.-P. Mainprice D. and Vigneresse J.-L. (2014), Rheological transition during large strain deformation of melting and crystallizing metapelites., in Journal of Geophysical Research-Solid Earth
, B119(5), 3971-3985.
Tumarkina E. Misra S. Burlini L. Connolly J.A.D. (2011), An experimental study of the role of shear deformation on partial melting of a synthetic metapelite, in Tectonophysics
, 503(1-2), 92-99.
Tumarkina E, Misra S, Burlini L, Connolly JAD (2011), An experimental study of the role of shear deformation on partial melting of a synthetic metapelite, in TECTONOPHYSICS
, 503(1-2), 92-99.
Misra S (2011), Deformation localization at the tips of shear fractures: An analytical approach, in TECTONOPHYSICS
, 503(1-2), 182-187.
Santanu Misra Jean‐Pierre Burg and David Mainprice (2011), Effect of finite deformation and deformation rate on partial melting and crystallization in metapelites, in JOURNAL OF GEOPHYSICAL RESEARCH
, 116(B02205), 1-9.
We wish to continue the SNF Project 200021-116153 for a post-doctoral (three years: 01.10.2010-30.09.2013) and a doctoral research (three years: 01.10.2010-30.09.2013) and also request a 1 year doctoral support (01.10.2010-30.09.2011) to allow the present PhD student (Rolf Bruijn) to finish in optimal conditions his work and publish his results. This proposal requests funding for amendment of the current experimental setup, the required consumables and limited fieldwork place our results into a geological perspective. The ETH rock-deformation laboratory is fully operational and this project is essential to continue its scientific activities. During the last 30 months we carried out a systematic experimental investigation on the quartz-muscovite system and illite-rich shale at elevated pressure and temperature, as proposed in the initial submission. The goals were successfully achieved within the stipulated time. In the first year (2007-08), the main focus was to i) find and characterize the suitable starting materials and ii) run pilot experiments in torsion to test the compatibility of the samples. The second year (2008-09) was dedicated at conducting a series of non-coaxial dynamic (torsion) and static experiments to explore i) the evolution of microstructures coupled with mineral reactions at large shear strain, ii) the role of deformation in partial melting, iii) the rheological transition from non-molten to molten rock during high shear strain, iv) the seismic properties of rocks during partial melting and v) the deformation of illite-rich shale. The results opened several challenging windows of study, particularly for an interacting binary (solid- fluid) system, which has wide applications for the physical and chemical behaviour of the deep crust. For the first time in the rock deformation community, we have been able to deform synthetic quartz-muscovite aggregates up to a finite shear strain of 15 and the rheology and phase relations of the deforming material were established in the light of mechanical data obtained during our experiments coupled with evolving microstructures. This allowed extrapolating the rheology, associated flow law and its high stress transition (Power Law Breakdown) to geological strain rates. We also focused on the dynamics of shear localization in melt-generating metapelites at syn-tectonic conditions. This work leads to at least six papers; one has already been published, one is under revision and two are ready for submission and rests are under preparation. In addition, seismic anisotropy, i.e. the directional dependency of the elastic properties of a rock, is being investigated in a series of synthetic quartz-muscovite aggregates as function of confining pressure and temperature. Results being acquired at the time this project-continuation is written will predictably be matter of more publications.The primary aim of the project continuation is to study the link between deformation and metamorphism in the quartz-muscovite system at different conditions with reference to the KASH system. We have observed that the rate and amount of partial melt generation and growth of new minerals (K-feldspar, sillimanite and biotite) during torsion experiments are 1.7 times higher than in static experiments. However, the experiments were conducted in the sillimanite field. Our goal is now to run deformation and static experiments (open and closed systems) in the andalusite and kyanite fields and redefine the phase diagram with an added parameter: Deformation. Clay minerals and muscovite dehydrate with temperature, resulting in local pore pressure build up and normal stress lowering. This project will also characterize the in-situ pore pressure increase during high strain torsion as a function of shear heating and mechanical weakening. As the laboratory is specialized in measuring seismic anisotropy of mono- and polycrystalline rocks at high pressure and temperature, and from plastically deformed individual crystals, this study will focus on the influence of different deformation mechanisms on the development of seismic anisotropy at the crustal scale.With the proposed research we want to keep our leading position by producing high quality scientific contributions in the international rock deformation community. The existing PhD student will continue on experimental deformation of illite-rich shale, while the new PhD student will focus specifically on characterizing and developing the theoretical and numerical thermodynamic model of the interacting solid-fluid system with the experimental data. The post-doc will conduct the more difficult experiments on quartz-muscovite aggregates involving wet (open and close system) and variable pore pressure in order to approach geologically more relevant conditions along with supervising the PhDs.