in this study, the development of structural elements and the relationship between these elements and dikes emplacements investigated by the field surveys and analysis of satellite images of the east dasht-e bayaz fault zone. in this area nnw-sse (t2) and nw-se trending dikes are which follow the fractures of the region. we measured geometric characters of dikes (such as thickness, attitude, di...

Recent observations have shown that shear waves trapped within lowvelocity fault zones may be the most sensitive measure of fault-zone structure (Li e t al. , 1994a, 1994b). Finite-difference simulations demonstrate the effects of several types of complexi ty on observations of fault-zone trapped waves. Overlying sediments with a thickness more than one or two fault-zone widths and fault-zone s...

Active deformation in Alborz range is due to N-S convergence between Arabia and Eurasia. This paper provides geomorphic traces of regional deformation in NW Iran in order to characterize active faulting on major faults. Soltanieh and North Zanjan fault systems are involved in convergence boundary extent between South Caspian Basin and Central Iran. Soltanieh and North Zanjan faults are major re...

S U M M A R Y We present a statistical analysis of focal mechanism orientations for nine California fault zones with the goal of quantifying variations of fault zone heterogeneity at seismogenic depths. The focal mechanism data are generated from first motion polarities for earthquakes in the time period 1983–2004, magnitude range 0–5, and depth range 0–15 km. Only mechanisms with good quality ...

We deployed a dense linear array of 45 seismometers across and along the San Andreas fault near Parkfield a week after the M 6.0 Parkfield earthquake on 28 September 2004 to record fault-zone seismic waves generated by aftershocks and explosions. Seismic stations and explosions were co-sited with our previous experiment conducted in 2002. The data from repeated shots detonated in the fall of 20...

Fault zones are thought to consist of regions with reduced seismic velocity. When sources are located in or close to these low-velocity zones, guided seismic head and trapped waves are generated which may be indicative of the structure of fault zones at depth. Observations above several fault zones suggest that they are common features of near fault radiation, yet their interpretation may be hi...

Alborz Mountains is a region of active deformation within Arabia-Eurasia collision zone. The study fault system in western Alborz comprises abundant evidence of active faulting accompanied by occurrence of historical earthquakes. Active tectonics of Manjil-Rudbar fault zone whose movement caused destructive 1990 Manjil-Rudbar earthquake was concentrated in this article through geomorphic and st...

Late Quaternary slip rates and satellite-based geodetic data for the western Great Basin constrain regional fault-slip distribution and evolution. The geologic slip rate on the Fish Lake Valley fault zone (the northwest extension of the Furnace Creek fault zone) increases northward from about 3 to 5 mm/yr, in agreement with modeled geodetic data. The increase coincides with the intersections of...

An offshore zone of faulting approximately 10 km from the southern California coast connects the seismically active strike-slip Newport–Inglewood fault zone in the Los Angeles metropolitan region with the active Rose Canyon fault zone in the San Diego area. Relatively little seismicity has been recorded along the offshore Newport–Inglewood Rose Canyon fault zone, although it has long been suspe...

The Izeh fault zone is a transverse fault zone with dextral strike slip (and some reverse component) in the Zagros Mountains (Iran). It causes some structural deformations. This fault zone is acting as eastern boundary of Dezful Embayment and forms subsidence of the embayment. The fault has been recognized using remote sensing techniques in conjunction with surface and subsurface analyses. The ...