In some subsurface urban development projects, bedrock faults intersecting with the tunnel path are inevitable. Due to high costs of it is necessary study behavior such concrete structures under fault movement risks. Using an advanced 3D numerical finite difference code and a plastic hardening constitutive model for soil, this paper examined performance straight oblique segmented Tabriz Subway ...

To determine factors controlling permeability variations within and adjacent to a fault-hosted geothermal reservoir at Dixie Valley, Nevada, we conducted borehole televiewer observations of wellbore failure (breakouts and cooling cracks) together with hydraulic fracturing stress measurements in six wells drilled into the Stillwater fault zone at depths of 2-3 km. Measurements in highly permeabl...

[1] The southwestern half of a 500 km long seismic gap in the central Kuril Island arc subduction zone experienced two great earthquakes with extensive preshock and aftershock sequences in late 2006 to early 2007. The nature of seismic coupling in the gap had been uncertain due to the limited historical record of prior large events and the presence of distinctive upper plate, trench and outer r...

Conjugate, or bimodal, fault patterns dominate the geological literature on shear failure. Based on Anderson's (1905) application of the Mohr-Coulomb failure criterion, these patterns have been interpreted from all tectonic regimes, including normal, strike-slip and thrust (reverse) faulting. However, a fundamental limitation of the Mohr-Coulomb failure criterion e and others that assume faults...

The results of numerical modelling show that the mechanical stratification of the crust provides the fundamental control on fault spacing and, ultimately, the mode of extension. Macroscopic pre-existing structures and weaknesses are often thought to govern the behaviour of continental crust under extension, and many prior studies have focussed on the effect of heterogeneities in triggering faul...

Using the method developed by Hardebeck and Shearer (2002, 2003) termed the HASH method, we calculate focal mechanisms for earthquakes that occurred in the southern California region from 1981 to 2010. When available, we use hypocenters refined with differential travel times from waveform cross correlation. Using both the P-wave first motion polarities and the S/P amplitude ratios computed from...

The eastern boundary of the Southern Cascades (Hat Creek Graben region), California, USA, is an extensively faulted volcanic corridor between the Cascade Range and Modoc Plateau. The morphology of the region is a result of plate motions associated with different tectonic provinces, faulting, and recurring volcanic activity, making it an ideal place to study the interrelationship between tectoni...

[1] We present the results of a series of 3-D boundary element calculations to investigate the effects of oceanic transform faults on stress state and fault development at adjacent mid-ocean ridge spreading centers. We find that the time-averaged strength of transform faults is low, and that on time scales longer than a typical earthquake cycle transform faults behave as zones of significant we...

[1] The Transantarctic Mountains (TAM) define the western flank of the West Antarctic rift system. Cape Surprise, near the Shackleton Glacier in the central TAM, is the only location along the range’s >3500 km length where upper Paleozoic Beacon Supergroup strata are down-faulted to near sea level. Previous studies have inferred a range front master normal fault accommodates extension and rock ...