Shear response of Fe-bearing MgSiO3 post-perovskite at lower mantle pressures
نویسندگان
چکیده
We investigate the shear response of possible slip systems activated in pure and Fe-bearing MgSiO(3) post-perovskite (PPv) through ab initio generalized stacking fault (GSF) energy calculations. Here we show that the [100](001) slip system has the easiest response to plastic shear among ten possible slip systems investigated. Incorporation of Fe(2+) decreases the strength of all slip systems but does not change the plastic anisotropy style. Therefore, pure and Fe-bearing MgSiO(3) PPv should demonstrate similar LPO patterns with a strong signature of the [100](001) slip system. An aggregate with this deformation texture is expected to produce a V(SH) > V(SV) type polarization anisotropy, being consistent with seismological observations.(Communicated by Ikuo KUSHIRO, M.J.A.).
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عنوان ژورنال:
دوره 89 شماره
صفحات -
تاریخ انتشار 2013