In situ X-ray and acoustic observations of deep seismic faulting upon phase transitions in olivine.

ABSTRACT: The activity of deep-focus earthquakes, which increases with depth from ~400 km to a peak at ~600 km, is enigmatic, because conventional brittle failure is unlikely to occur at elevated pressures. It becomes increasingly clear that pressure-induced phase transitions of olivine are responsible for the occurrence of the earthquakes, based on deformation experiments under pressure. However, many such experiments were made using analogue materials and those on mantle olivine are required to verify the hypotheses developed by these studies. Here we report the results of deformation experiments on (Mg,Fe)₂SiO₄ olivine at 11-17 GPa and 860-1350 K, equivalent to the conditions of the slabs subducted into the mantle transition zone. We find that throughgoing faulting occurs on

SUBMITTER: Ohuchi T 

PROVIDER: S-EPMC9477848 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature