Skip to main content


Table 1 List of parameters

From: Geometrical dependence on the stress and slip tendency acting on the subduction megathrust of the Nankai seismogenic zone off Kumano

Notation Definition Assignment/derivation for this study
Sign of stress   Positive for compression
ψ Dip azimuth (clockwise from north)  
α Angle between SH (slip) direction and dip azimuth α = ψ -(− 55°)
δ Dip angle (positive downward)  
σ 1 Maximum compressional principal stress σ1 =SH
σ 2 Intermediate principal stress σ2 = Sh
σ 3 Minimum principal stress σ3 = Sv
S H Maximum (compressional) horizontal principal stress SH = rSv = 1.2Sv
S h Minimum horizontal principal stress Sh = Sv
S v Vertical stress (overburden) Calculated from 3D density
P p Pore fluid pressure Pp = λSv = 0.7Sv
P hyd Hydrostatic pore fluid pressure Phyd = 0.6Sv
σ H Effective maximum horizontal stress σH = SH - Pp
σ h Effective minimum horizontal stress σh = Sh - Pp
σ v Effective vertical stress σv = Sv-Pp
Σ Stress tensor  
r SH/Sv r = 1.2
λ Pp/Sv λ = 0.7, 0.94
λ* (Pp - Phyd) / (SvPhyd) λ* = 0.2, 0.85
σ n Normal stress  
σ n_e Effective normal stress σn_e = σn - Pp(Eq. (7))
τ Shear stress Eq. (8)
Ts Slip tendency Ts = τ/σn_e, (Eq. (9))
μ Intrinsic friction coefficient μ = 0.6
SL Slip likelihood SL = Ts/μ
V p P-wave velocity