We show that a new subduction zone can initiate at a preexisting dipping fault zone with reasonable plate forces, consistent with what is observed in the western Pacific. The dynamics of subduction initiation within a viscoelastic medium has been systematically explored with the finite element method. We investigate the compression of oceanic lithosphere with hoth force and velocity boundary co...

The 1999 Izmit earthquake (17/08/1999, Mw=7.4) was one of the largest earthquakes in the past 100 years in the northwestern region of Turkey. This earthquake occurred along the Izmit-Sapanca fault within the Northern Anatolian Fault Zone. Variations in the generalized fractal dimensions (Dq) of clustering in time and space, the Gutenberg-Richter b-value, and earthquake frequency (N) are evaluat...

Field observations of maturely slipped faults show a generally broad zone of damage by cracking and granulation. Nevertheless, large shear deformation, and therefore heat generation, in individual earthquakes takes place with extreme localization to a zone <1–5 mm wide within a finely granulated fault core. Relevant fault weakening processes during large crustal events are therefore likely to b...

[1] Coseismic deformation of the ground can be measured from aerial views taken before and after an earthquake. We chose the area of the Kickapoo-Landers step over along the 1992 Landers earthquake zone, using air photos (scale 1:40,000) scanned at 0.4 m resolution. Two photos acquired after the earthquake are used to assess the accuracy and to evaluate various sources of noise. Optical distort...

[1] The Gibraltar Arc in the western Mediterranean consists of the Betic and Rif Alpine chains and the Alboran Sea Basin. Four types of stress indicators (wellbore breakouts, earthquake focal plane mechanisms, young geologic fault slip data, and hydraulic fracture orientations) indicate a regional NW–SE compressive stress field resulting from Africa-Eurasia plate convergence. In some particular...

We used a new data set of relocated earthquakes recorded by the Seismic Network of Northeastern Sonora, Mexico (RESNES) to characterize the attenuation of S-waves in the fault zone of the 1887 Sonora earthquake (M w 7.5). We determined spectral attenuation functions for hypocentral distances (r) between 10 and 140 km using a nonparametric approach and found that in this fault zone the spectral ...

This paper discusses Coulomb failure criteria for brittle deformation of intact rock and fault gouge. Data are presented from laboratory experiments designed to identify the critical gouge layer thickness required to effect a transition from the standard Coulomb criterion to a modified failure law (referred to as Coulomb plasticity) appropriate for simple shear of a gouge layer. Experiments wer...

Does motor efficiency relate to “going green”? While the term going green originally applied to the release of greenhouse gasses, it has been broadened to include waste and inefficiency associated with factory operations in general and motors specifically. The green movement as it relates to motors is the result of industry becoming environmentally conscious with a wary eye on reducing its carb...

The presence of radon in drinking water causes health risks associated with exposure from both inhalation and ingestion. Since the studies show that faults near the water resources have a critical effect on the concentration of radon, Kouhbanan active fault zone, to find water resources  with high radon concentration was chosen for the following investigation. Water samples were taken from all ...