We use three-dimensional dynamic (spontaneous) rupture models to investigate the nearly simultaneous ruptures of the Susitna Glacier thrust fault and the Denali strike-slip fault. With the 1957 Mw 8.3 Gobi-Altay, Mongolia, earthquake as the only other well-documented case of significant, nearly simultaneous rupture of both thrust and strike-slip faults, this feature of the 2002 Denali fault ear...

[1] Mechanical models examine deformation within eight different structural cross sections proposed by Davis et al. [1989] and Shaw and Suppe [1996] along a northeastsouthwest transect across the Los Angeles Basin, California. Horizontal contraction of the models, constrained by geodetic measurements, yields varying dip-slip rates along frictionally sliding faults within the different cross sec...

fault zones and fault-related fracture systems control the mechanical behaviors and fluid-flow properties of the earth’s crust. furthermore, nowadays, modeling is being increasingly used in order to understand the behavior of rock masses, and to determine their characteristics. in this work, fault zones and fracture patterns are reviewed, and also comprehensive studies are carried out on the fr...

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...

Recent modeling studies have explored whether earthquakes begin with a large aseismic nucleation process or initiate dynamically from the rapid growth of a smaller instability in a “cascade-up” process. To explore such a case in the laboratory, we study the initiation of dynamic rupture (stick slip) of a smooth saw-cut fault in a 76mm diameter cylindrical granite laboratory sample at 40–120MPa ...

a r t i c l e i n f o Recent high-resolution GPS and seismological data reveal that tectonic faults exhibit complex, multi-mode slip behavior including earthquakes, creep events, slow and silent earthquakes, low-frequency events and earthquake afterslip. The physical processes responsible for this range of behavior and the mechanisms that dictate fault slip rate or rupture propagation velocity ...

The Pasadena earthquake (ML ~4.9) occurred on 3 December 1988, at a depth of 16 km. The hypocenters of the earthquake and its aftershocks define a eastnortheast striking, steeply northwest-dipping surface that projects up to the active surficial trace of the Raymond fault. One of the nodal planes of the focal mechanism of the earthquake parallels the Raymond fault with left-lateral strikeslip m...

Technical Abstract We determined orientations of principal stresses around the San Andreas Fault (SAF) system in the greater San Francisco Bay Area and regions further north along the strike-slip plate boundary. Stress orientations, as well as a ratio between stress magnitudes, were determined by inversions of approximately 6000 earthquake fault plane solutions, divided into ~100 groups based o...

The Mw 6.1 South Napa earthquake occurred near Napa, California, on 24 August 2014 at 10:20:44.03 (UTC) and was the largest inland earthquake in northern California since the 1989 Mw 6.9 Loma Prieta earthquake. The first report of the earthquake from the Northern California Earthquake Data Center (NCEDC) indicates a hypocentral depth of 11.0 km with longitude and latitude of (122.3105° W, 38.21...

Abundant geological, seismological and experimental evidence of the heterogeneous structure of natural faults motivates the theoretical and computational study of the mechanical behavior of heterogeneous frictional interfaces. Fault zones are composed of a mixture of materials with contrasting strength, which may affect the spatial variability of seismic coupling, the location of high-frequency...