We analyze GPS data observed before and after the 2001 Mw 7.8 Kokoxili earthquake in northern Tibet to derive the coseismic deformation field of that earthquake. Using this coseismic displacement data set and geologically mapped surface break measurements, we invert for the coseismic slip distribution along the seismogenic East Kunlun fault. Our result shows that the earthquake on average ruptu...

The source processes of the 4 January 1970, Tonghai earthquake (Ms = 7.5) and the 6 February 1973, Luhuo earthquake (Ms = 7.5) in southwestern China were investigated using an inversion technique on the very complex body waves. The two earthquakes were associated with 48 and 90 km of surficial strike-slip rupture, respectively, and the distribution of displacement with distance along the fault ...

We explore features of rupture dynamics that (1) lead to slip heterogeneity in earthquake ruptures and (2) maintain conditions that permit slip heterogeneity in subsequent events. Our 3-D finite-element simulations of magnitude 7 events on a vertical, planar strike-slip fault show that the conditions that lead to slip heterogeneity remain in place after large events when the initial shear stres...

[1] We calculated static stress changes from the devastating M = 7.6 earthquake that shook Kashmir on 8 October, 2005. We mapped Coulomb stress change on target fault planes oriented by assuming a regional compressional stress regime with greatest principal stress directed orthogonally to the mainshock strike. We tested calculation sensitivity by varying assumed stress orientations, target-faul...

This paper provides an overview to detect, locate, and characterize fault in structural and mechanical systems using various methods. Since last few decades experimentally measured frequencies has been extensively used to crack detection. The relationships between frequency changes and structural damage are discussed. Various reverse techniques proposed for detecting fault using natural frequen...

We develop a 2D slip-weakening description of a self-healing slip pulse that propagates dynamically in a steady-state configuration. The model is used to estimate patterns of off-fault secondary failure induced by the rupture, and also to infer fracture energies G for large earthquakes. This extends an analysis for a semiinfinite rupture (Poliakov et al., 2002) to the case of a finite slipping ...

[1] Seismic inversions show that earthquake risetimes may be much shorter than the overall rupture duration, indicating that earthquakes may propagate as self‐healing, pulse‐like ruptures. Several mechanisms for producing pulse‐like ruptures have been proposed, including velocity‐weakening friction, interaction of dynamic rupture with fault geometry and local heterogeneity, and effect of bimate...

[1] Using a finite element method for elastoplastic dynamic analysis, we examine the effects of a low-velocity fault zone (LVFZ) surrounding a fault on a spontaneous dynamic earthquake rupture. A Mohr-Coulomb failure criterion is used to characterize nonelastic off-fault response to earthquake ruptures. We find that the presence of a LVFZ alters the distribution of off-fault plastic strain and ...

Near-trench slip during large megathrust earthquakes (megaquakes) is an important factor in the generation of destructive tsunamis. We proposed a new approach to assessing the near-trench slip potential quantitatively by integrating laboratory-derived properties of fault materials and simulations of fault weakening and rupture propagation. Although the permeability of the sandy Nankai Trough ma...

We conducted paleoseismic studies in a closed depression along the San Andreas fault on the north flank of Frazier Mountain near Frazier Park, California. We recognized two earthquake ruptures in our trench exposure and interpreted the most recent rupture, event 1, to represent the historical 1857 earthquake. We also exposed evidence of an earlier surface rupture, event 2, along an older group ...