A stochastic fault model: 1. Static case

Andrews, D. J.

doi:10.1029/jb085ib07p03867

Cited by 282 publications

(201 citation statements)

References 28 publications

Supporting

Mentioning

195

Contrasting

Order By: Relevance

“…While the role of fixed heterogeneities related to fault structure and properties versus heterogeneity arising solely from the nonlinear dynamics of rupture propagation is a source of active controversy, it is becoming apparent that both factors are present and contribute significantly to observed variations in coseismic slip (Shaw, 2004). The important implication of this rich field of studies is that (a) whatever the mechanism, the final slip distribution of a rupture can be characterized as being self-affine (Andrews, 1980); and (b) this slip distribution, though deterministic and causal, is difficult to predict.…”

Section: Earthquake Physicsmentioning

confidence: 99%

Differences in tsunami generation between the December 26, 2004 and March 28, 2005 Sumatra earthquakes

et al. 2006

View full text Add to dashboard Cite

Source parameters affecting tsunami generation and propagation for the M w > 9.0 December 26, 2004 and the M w = 8.6 March 28, 2005 earthquakes are examined to explain the dramatic difference in tsunami observations. We evaluate both scalar measures (seismic moment, maximum slip, potential energy) and finite-source representations (distributed slip and far-field beaming from finite source dimensions) of tsunami generation potential. There exists significant variability in local tsunami runup with respect to the most readily available measure, seismic moment. The local tsunami intensity for the December 2004 earthquake is similar to other tsunamigenic earthquakes of comparable magnitude. In contrast, the March 2005 local tsunami was deficient relative to its earthquake magnitude. Tsunami potential energy calculations more accurately reflect the difference in tsunami severity, although these calculations are dependent on knowledge of the slip distribution and therefore difficult to implement in a real-time system. A significant factor affecting tsunami generation unaccounted for in these scalar measures is the location of regions of seafloor displacement relative to the overlying water depth. The deficiency of the March 2005 tsunami seems to be related to concentration of slip in the down-dip part of the rupture zone and the fact that a substantial portion of the vertical displacement field occurred in shallow water or on land. The comparison of the December 2004 and March 2005 Sumatra earthquakes presented in this study is analogous to previous studies comparing the 1952 and 2003 Tokachi-Oki earthquakes and tsunamis, in terms of the effect slip distribution has on local tsunamis. Results from these studies indicate the difficulty in rapidly assessing local tsunami runup from magnitude and epicentral location information alone.

show abstract

Section: Earthquake Physicsmentioning

confidence: 99%

Differences in tsunami generation between the December 26, 2004 and March 28, 2005 Sumatra earthquakes

et al. 2006

View full text Add to dashboard Cite

show abstract

“…[9] We compute the static shear-stress change from the refined coseismic slip model using a fast Fourier transform (FFT) method [Andrews, 1980;Ripperger and Mai, 2004], chosen because of its computational efficiency that allows the exploration of multiple model parameters. The 20 km × 20 km gridded slip model is initially downsampled via bicubic interpolation to a 1 km × 1 km grid, which serves as the input for the stress-change calculation.…”

Section: Minimum Stress Drop From the 27 February 2010 Maule Earthquakementioning

confidence: 99%

Estimates of stress drop and crustal tectonic stress from the 27 February 2010 Maule, Chile, earthquake: Implications for fault strength

et al. 2011

View full text Add to dashboard Cite

[1] The great 27 February 2010 M w 8.8 earthquake off the coast of southern Chile ruptured a ∼600 km length of subduction zone. In this paper, we make two independent estimates of shear stress in the crust in the region of the Chile earthquake. First, we use a coseismic slip model constrained by geodetic observations from interferometric synthetic aperture radar (InSAR) and GPS to derive a spatially variable estimate of the change in static shear stress along the ruptured fault. Second, we use a static force balance model to constrain the crustal shear stress required to simultaneously support observed fore-arc topography and the stress orientation indicated by the earthquake focal mechanism. This includes the derivation of a semianalytic solution for the stress field exerted by surface and Moho topography loading the crust. We find that the deviatoric stress exerted by topography is minimized in the limit when the crust is considered an incompressible elastic solid, with a Poisson ratio of 0.5, and is independent of Young's modulus. This places a strict lower bound on the critical stress state maintained by the crust supporting plastically deformed accretionary wedge topography. We estimate the coseismic shear stress change from the Maule event ranged from −6 MPa (stress increase) to 17 MPa (stress drop), with a maximum depth-averaged crustal shear-stress drop of 4 MPa. We separately estimate that the plate-driving forces acting in the region, regardless of their exact mechanism, must contribute at least 27 MPa trench-perpendicular compression and 15 MPa trench-parallel compression. This corresponds to a depth-averaged shear stress of at least 7 MPa. The comparable magnitude of these two independent shear stress estimates is consistent with the interpretation that the section of the megathrust fault ruptured in the Maule earthquake is weak, with the seismic cycle relieving much of the total sustained shear stress in the crust.

show abstract

“…It is well known that the powerlaw moment-frequency scaling implied by the GR relation indicates that the earthquake rupture process is scale invariant (Andrews, 1980;Rundle, 1989). Thus, it follows that deviations from the GR relation, which are expected, by Correspondence to: M. H. Heimpel (mheimpel@phys.ualberta.ca) physical and geometrical constraints, at both small and large ends of earthquake size-frequency distributions, indicate the effect of characteristic scales of the fault or fault system.…”

Section: Introductionmentioning

confidence: 99%

Characteristic scales of earthquake rupture from numerical models

Heimpel

2003

Nonlin. Processes Geophys.

View full text Add to dashboard Cite

Abstract. Numerical models of earthquake rupture are used to investigate characteristic length scales and size distributions of repeated earthquakes on vertical, planar fault segments. The models are based on exact solutions of static three-dimensional (3-D) elasticity. Dynamical rupture is approximated by allowing the static stress field to expand from slip motions at a single velocity. To show how the vertical fault width affects earthquake size distributions for a broad range of fault behaviors, two different fault strength models are used; a smooth model and a heterogeneous asperity model. The smooth model is a simplified version of the Dieterich-Ruina rate and state dependent friction law. The heterogeneous asperity model uses a slip-dependent random powerlaw strength distribution. It is shown that the characteristic scale of fault segmentation is proportional to the vertical width of a seismogenic fault. This conclusion holds for both the smooth and the heterogeneous models. For the smooth models characteristic quake distributions result, with populations of large events that are obviously distinct from smaller events. The distributions of large events have well-defined mean lengths and moments. The heterogeneous models result in Gutenberg-Richter (GR) powerlaw distributions of event sizes up to a characteristic quake size. Quakes larger than the characteristic size fall off the GR distribution such that the powerlaw would greatly overestimate the probability of occurrence of the larger events.

show abstract

A stochastic fault model: 1. Static case

Cited by 282 publications

References 28 publications

Differences in tsunami generation between the December 26, 2004 and March 28, 2005 Sumatra earthquakes

Differences in tsunami generation between the December 26, 2004 and March 28, 2005 Sumatra earthquakes

Estimates of stress drop and crustal tectonic stress from the 27 February 2010 Maule, Chile, earthquake: Implications for fault strength

Characteristic scales of earthquake rupture from numerical models

Contact Info

Product

Resources

About