Stress Distribution in the Vicinity of Right Strike-Slip Fault, a Numerical Approach

Budi Sulistianto, Yoshiaki Mizuta

J. of MMIJ, Vol.115, No.9, p.651-659, 1999

When Fault exists in the formation, the local stresses in the shallow depth will be affected by presence of slip or displacement on fault and topography. If the trance of fault is not straight, the stress distribution near fault becomes more complicated. This feature is studied numerically using boundary element method. Related to this problem, a numerical procedure of 2 and 3 dimensional coupled fictitious stress method and displacement discontinuity method, which takes joint element into consideration, is adopted. A sinusoidal fault trace is used to modelize the non-straight strike-slip fault in 2 dimensions, while a sinusoidal fault plane buried in the middle of symmetrical valley is used as numerical model study in 3 dimensions. This model is then applied to the Mozumi Sukenobu fault as field case study. Our finding on local stress near fault is consistent with filed measurement. If the far filed stress is defined in proportion to depth, our finding also predicts that the applied far field stress in the Mozumi Sukenobu fault is in compression with s_Ho oriented at -40°from fault strike and the magnitudes of far field stress components are s_vo =rgh, s_Ho =0.74 and s_ho =0.5s_vo.

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