Dislocation interactions in olivine control postseismic creep of the upper mantle

Changes in stress applied to mantle rocks, such as those imposed by earthquakes, induce a period of evolution viscosity and microstructure. This transient creep is often modelled based on transfer among slip systems due grain interactions. However, recent experiments have demonstrated that the intragranular accumulation stresses dislocations dominant cause strain hardening olivine at low temperatures, raising question whether same process contributes higher temperatures. Here, we demonstrate samples deformed 25{\deg}C or 1150 1250{\deg}C both contain heterogeneities ~1 GPa are imparted correlation lengths micrometre. The similar distributions formed temperature regimes indicate also provides contribution high results motivate new generation models capture these processes may refine predictions evolving over earthquake cycle.