biostudies-literatureNakata RJapan Society for the Promotion of Science6480https://www.ebi.ac.uk/biostudies/studies/S-EPMC7979718biostudies-literatureUnknown11(1)There are significant differences between the middle and southern segments of the Japan Trench in terms of the seismic and aseismic slips on the plate interface and seismic velocity structures. Although the large coseismic slip of the 2011 Tohoku-Oki earthquake was limited to the middle segment, the observed negative residual gravity anomaly area in the southern segment corresponds to the postseismic slip area of the Tohoku-Oki earthquake. A density distribution model can explain the different slip behaviours of the two segments by considering their structural differences. The model indicates that the plate interface in the south was covered with a thick channel layer, as indicated by seismic survey imaging, and this layer resulted in a residual gravity anomaly. Numerical simulations whichScientific reportsPresence of interplate channel layer controls of slip during and after the 2011 Tohoku-Oki earthquake through the frictional characteristics.PMC7979718JP19H05596Nakata RMiura SHori THino RfalsePresence of interplate channel layer controls of slip during and after the 2011 Tohoku-Oki earthquake through the frictional characteristics.There are significant differences between the middle and southern segments of the Japan Trench in terms of the seismic and aseismic slips on the plate interface and seismic velocity structures. Although the large coseismic slip of the 2011 Tohoku-Oki earthquake was limited to the middle segment, the observed negative residual gravity anomaly area in the southern segment corresponds to the postseismic slip area of the Tohoku-Oki earthquake. A density distribution model can explain the different slip behaviours of the two segments by considering their structural differences. The model indicates that the plate interface in the south was covered with a thick channel layer, as indicated by seismic survey imaging, and this layer resulted in a residual gravity anomaly. Numerical simulations which2021-01-01T00:00:00Z2021 Mar2025-04-04T22:00:54.463Z2025-04-04T22:00:54.463ZS-EPMC79797183374204910.1038/s41598-021-86020-9