Residual elastic field in two welded half spaces due to non uniform slip along a long strike slip fault

Abstract

The problem of the static deformation of two homogeneous, isotropic and perfectly elastic half spaces in welded contact caused by non uniform slip along a vertical strike slip fault of infinite length and finite width is studied. Four slip profiles are considered : elliptic b=b₀ (1-h²/L²)½, parabolic b = b₀(1-h²/L²), linear b = b₀ (l-h/L) and cubic b = b₀ (1-h²/L²)^3/2 where b is the slip at distance h from the interface, bo is the interface slip and L is the fault width. The deformation corresponding to the four non uniform slip profiles is compared with the deformation due to uniform slip, assuming the source potency ∫^L₀ b(h) dh to be the same. The parity in source potency is achieved by varying the fault width L, keeping the interface slip b₀ constant. Contour maps showing the displacement and stress fields around a long vertical strike slip fault are presented. It is found that the effect of non uniformity in slip in the near field is noteworthy. The far field is not affected significantly by the non uniformity in slip, i.e. the far field cannot see the details of the slip on the fault.