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1. Viscous anisotropy of textured olivine aggregates, Part 1: Measurement of the magnitude and evolution of anisotropy

   https://doi.org/10.1016/j.epsl.2016.04.008  

   Hansen, Lars N. ; Warren, Jessica M. ; Zimmerman, Mark E. ; Kohlstedt, David L. ( July 2016 , Earth and Planetary Science Letters)
2. Effects of pressure on diffusion creep in wet olivine aggregates

   https://doi.org/10.1016/j.pepi.2022.106840  

   Silber, Reynold E. ; Girard, Jennifer ; Karato, Shun-ichiro ( March 2022 , Physics of the Earth and Planetary Interiors)
3. Laboratory investigation of mechanisms for phase mixing in olivine + ferropericlase aggregates

   https://doi.org/10.1098/rsta.2017.0417  

   Wiesman, Harison S. ; Zimmerman, Mark E. ; Kohlstedt, David L. ( October 2018 , Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences)
4. Global Analysis of Experimental Data on the Rheology of Olivine Aggregates

   https://doi.org/10.1029/2018JB016558  

   Jain, Chhavi ; Korenaga, Jun ; Karato, Shun‐ichiro ( January 2019 , Journal of Geophysical Research: Solid Earth)

   Following the reanalysis of individual experimental runs of some widely cited studies (Jain et al., 2018,https://doi.org/10.1002/2017JB014847), we revisit the global data analysis of Korenaga and Karato (2008,https://doi.org/10.1029/2007JB005100) with a significantly improved version of their Markov chain Monte Carlo inversion. Their algorithm, previously corrected by Mullet et al. () to minimize potential parameter bias, is further modified here to estimate more efficiently interrun biases in global data sets. Using the refined Markov chain Monte Carlo inversion technique, we simultaneously analyze experimental data on the deformation of olivine aggregates compiled from different studies. Realistic composite rheological models, including both diffusion and dislocation creep, are adopted, and the role of dislocation‐accommodated grain boundary sliding is also investigated. Furthermore, the influence of interrun biases on inversion results is studied using experimental and synthetic data. Our analysis shows that existing data can tightly constrain the grain‐size exponent for diffusion creep at ∼2, which is different from the value commonly assumed (p= 3). Different data sets and model assumptions, however, yield nonoverlapping estimates on other flow‐law parameters, and the flow‐law parameters for grain boundary sliding are poorly resolved in most cases. We thus provide a few plausible candidate flow‐law models for olivine rheology to facilitate future geodynamic modeling. The availability of more data that explore a wider range of experimental conditions, especially higher pressures, is essential to improve our understanding of upper mantle rheology.

    

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5. Shear‐Wave Splitting in the Mantle Wedge: Role of Elastic Tensor Symmetry of Olivine Aggregates

   https://doi.org/10.1029/2022GL100143  

   Kenyon, L. M. ; Wada, I. ( October 2022 , Geophysical Research Letters)

   Using a 3‐D mantle wedge flow field for a generic oblique subduction system, we calculate elastic tensors of mineral aggregates in the mantle wedge for A‐, B‐, C‐, and E‐type olivine crystal preferred orientations (CPO) and apply the calculated elastic tensor in the forward calculation of shear‐wave splitting (SWS) through the mantle wedge. We find that the hexagonal approximation of the full tensor does not affect the SWS parameters (the fast direction and the delay time) significantly for all CPO types except that the delay time for C‐type CPO becomes shorter. Additionally, we find that despite the 3‐D mantle flow field that results from oblique subduction, the fast direction is margin‐normal for A‐, C‐ and E‐type CPOs and margin‐parallel for B‐type CPO.

    

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