Overriding Plate Deformation and Topography During Slab Rollback and Slab Rollover: Insights From Subduction Experiments

Some subduction zones in nature show mainly overriding plate (OP) extension and low topography, others shortening elevated topography. Here we investigate how end-member modes (trench retreat with slab rollback trench advance rollover) affect deformation (OPD), topography mantle flow time-evolving three-dimensional fully-dynamic analog models using particle image velocimetry (PIV). We conduct two sets of experiments, one which is characterized by retreat, the other advance. Experiments showing continuous experience overall OP extension, while experiments dominated shortening. Both present fore-arc intra-arc extension. Our indicate that OPD driven horizontal at base inducing a viscous drag force (FD), determined gradient shear rate d?????/dx, controls trench-normal FD. Furthermore, large-scale trenchward tilting an subsidence are observed landward uplift during long-term The types different can be ascribed to downward component upward flow, respectively, thus represent forms dynamic provide possible mechanism for Makran zone. This article protected copyright. All rights reserved.