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Table 1 Summary of the physical parameters controlling fault dynamics and viscoelastic flow

From: Structural control and system-level behavior of the seismic cycle at the Nankai Trough

Segment A—accretionary prism
 Static friction coefficient\(\mu\)0.1
 Effective normal stress\(\bar{\sigma }\)35 MPa
 Direct-effect parametera\(5.85\times 10^{-2}\)
 Steady-state parameter (velocity-weakening)\(b-a\)\(1.5\times 10^{-3}\)
 Characteristic weakening distanceL\(4\,\hbox {cm}\)
 Loading rate\(V_{\rm L}\)\(1.2\times 10^{-9}\,\hbox {m/s}\)
 Segment widthW\(41.75\,\hbox {km}\)
Segment B—seismogenic zone
 Static friction coefficient\(\mu\)0.6
 Effective normal stress\(\bar{\sigma }\)\(20\,\hbox {MPa}\)
 Direct-effect parametera\(7.6\times 10^{-3}\)
 Steady-state parameter (velocity-weakening)\(b-a\)\(2.4\times 10^{-3}\)
 Characteristic weakening distanceL\(8\,\hbox {mm}\)
 Loading rate\(V_{\rm L}\)\(1.8\times 10^{-9}\,\hbox {m/s}\)
 Segment widthW\(148.75\,\hbox {km}\)
Segment C—metamorphic belt (mantle wedge corner)
 Static friction coefficient\(\mu\)0.6
 Effective normal stress\(\bar{\sigma }\)\(20\,\hbox {MPa}\)
 Direct-effect parametera\(2\times 10^{-3}\)
 Steady-state parameter (velocity-weakening)\(b-a\)\(4.5\times 10^{-4}\)
 Characteristic weakening distanceL\(4.1\,\hbox {mm}\)
 Loading rate\(V_{\rm L}\)\(1.8\times 10^{-9}\,\hbox {m/s}\)
 Segment widthW\(24\,\hbox {km}\)
Segment D—mantle lid
 Static friction coefficient\(\mu\)0.6
 Effective normal stress\(\bar{\sigma }\)\(20\,\hbox {MPa}\)
 Direct-effect parametera\(2\times 10^{-3}\)
 Steady-state parameter (weakening near velocity-neutral)\(b-a\)\(2\times 10^{-4}\)
 Characteristic weakening distanceL\(0.7\,\hbox {mm}\)
 Loading rate\(V_{\rm L}\)\(1.8\times 10^{-9}\,\hbox {m/s}\)
 Segment widthW\(32\,\hbox {km}\)
Segment E—mantle wedge
 Static friction coefficient\(\mu\)0.6
 Effective normal stress\(\bar{\sigma }\)\(40\,\hbox {MPa}\)
 Direct-effect parametera\(1\times 10^{-2}\)
 Steady-state parameter (velocity-strengthening)\(a-b\)\(2\times 10^{-3}\)
 Characteristic weakening distanceL\(2.5\,\hbox {cm}\)
 Loading rate\(V_{\rm L}\)\(1.8\times 10^{-9}\,\hbox {m/s}\)
 Segment widthW\(53.5\,\hbox {km}\)
Viscoelastic substrate—upper mantle, oceanic asthenosphere
 Background strain rate\(\dot{\varepsilon }^0_{22}\)\(-10^{-15}\hbox { s}^{-1}\)
 Basal mantle temperatureT\(1673\,\hbox {K}\)
 PrefactorA\(90\hbox { MPa}^{-n}\hbox {s}^{-1}\hbox {(ppm H/Si)}^{-r}\)
 Power-law stress exponentn3.5
 Activation energyE\(460\,\hbox {kJ/mol}\)
 Activation volume\(\Omega\)\(11\times 10^{-6}\hbox { m}^3/\hbox {mol}\)
 Water content\(C_{\rm OH}\)1000 (ppm H/Si)
 Water content exponentr1.2
  1. The model assumes uniform elastic properties with a shear modulus of \(G=30\,\hbox {GPa}\), Poisson’s ratio \(\nu =0.25\), and shear wave speed \(V_S=3\times 10^{3}\,\hbox {m/s}\). The reference slip velocity is \(V_0=10^{-6}\,\hbox {m/s}\)