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 parameter | a | \(5.85\times 10^{-2}\) |
 Steady-state parameter (velocity-weakening) | \(b-a\) | \(1.5\times 10^{-3}\) |
 Characteristic weakening distance | L | \(4\,\hbox {cm}\) |
 Loading rate | \(V_{\rm L}\) | \(1.2\times 10^{-9}\,\hbox {m/s}\) |
 Segment width | W | \(41.75\,\hbox {km}\) |
Segment B—seismogenic zone | ||
 Static friction coefficient | \(\mu\) | 0.6 |
 Effective normal stress | \(\bar{\sigma }\) | \(20\,\hbox {MPa}\) |
 Direct-effect parameter | a | \(7.6\times 10^{-3}\) |
 Steady-state parameter (velocity-weakening) | \(b-a\) | \(2.4\times 10^{-3}\) |
 Characteristic weakening distance | L | \(8\,\hbox {mm}\) |
 Loading rate | \(V_{\rm L}\) | \(1.8\times 10^{-9}\,\hbox {m/s}\) |
 Segment width | W | \(148.75\,\hbox {km}\) |
Segment C—metamorphic belt (mantle wedge corner) | ||
 Static friction coefficient | \(\mu\) | 0.6 |
 Effective normal stress | \(\bar{\sigma }\) | \(20\,\hbox {MPa}\) |
 Direct-effect parameter | a | \(2\times 10^{-3}\) |
 Steady-state parameter (velocity-weakening) | \(b-a\) | \(4.5\times 10^{-4}\) |
 Characteristic weakening distance | L | \(4.1\,\hbox {mm}\) |
 Loading rate | \(V_{\rm L}\) | \(1.8\times 10^{-9}\,\hbox {m/s}\) |
 Segment width | W | \(24\,\hbox {km}\) |
Segment D—mantle lid | ||
 Static friction coefficient | \(\mu\) | 0.6 |
 Effective normal stress | \(\bar{\sigma }\) | \(20\,\hbox {MPa}\) |
 Direct-effect parameter | a | \(2\times 10^{-3}\) |
 Steady-state parameter (weakening near velocity-neutral) | \(b-a\) | \(2\times 10^{-4}\) |
 Characteristic weakening distance | L | \(0.7\,\hbox {mm}\) |
 Loading rate | \(V_{\rm L}\) | \(1.8\times 10^{-9}\,\hbox {m/s}\) |
 Segment width | W | \(32\,\hbox {km}\) |
Segment E—mantle wedge | ||
 Static friction coefficient | \(\mu\) | 0.6 |
 Effective normal stress | \(\bar{\sigma }\) | \(40\,\hbox {MPa}\) |
 Direct-effect parameter | a | \(1\times 10^{-2}\) |
 Steady-state parameter (velocity-strengthening) | \(a-b\) | \(2\times 10^{-3}\) |
 Characteristic weakening distance | L | \(2.5\,\hbox {cm}\) |
 Loading rate | \(V_{\rm L}\) | \(1.8\times 10^{-9}\,\hbox {m/s}\) |
 Segment width | W | \(53.5\,\hbox {km}\) |
Viscoelastic substrate—upper mantle, oceanic asthenosphere | ||
 Background strain rate | \(\dot{\varepsilon }^0_{22}\) | \(-10^{-15}\hbox { s}^{-1}\) |
 Basal mantle temperature | T | \(1673\,\hbox {K}\) |
 Prefactor | A | \(90\hbox { MPa}^{-n}\hbox {s}^{-1}\hbox {(ppm H/Si)}^{-r}\) |
 Power-law stress exponent | n | 3.5 |
 Activation energy | E | \(460\,\hbox {kJ/mol}\) |
 Activation volume | \(\Omega\) | \(11\times 10^{-6}\hbox { m}^3/\hbox {mol}\) |
 Water content | \(C_{\rm OH}\) | 1000 (ppm H/Si) |
 Water content exponent | r | 1.2 |