It is known that plate boundaries in subduction zones show heterogeneous slip nature with strongly coupled seismogenic zones and various types of episodic tremor and slip (ETS) zones. In order to examine the petrological controls on the large-scale structure, we compared recent geophysical observations in the Shikoku area, southwest Japan with petrological models of the hanging wall mantle wedge. As a result, we found a close relationship between mineral assemblages in the mantle wedge and the characteristics of slow slip behaviour recorded in the Shikoku area: Short-term ETSs take place in the antigorite + olivine stability field and silent long-term slow slip events