investigation of velocity structure based on seismic wave propagation have been performed in recent years in different parts of iran that results obtained is effective in the analysis of seismic zones and locate earthquakes with reasonable accuracy. on a broad scale, the seismotectonics of southern iran are controlled by active convergence between the arabian and eurasian tectonic plates that a...

To eliminate the location error of MS/AE (microseismic/acoustic emission) monitoring systems caused by the measurement deviations of the wave velocity, a MS/AE source location method using P-wave and S-wave arrivals for unknown velocity system (PSAFUVS) was developed. Arrival times of P-wave and S-wave were used to calculate and fit the MS/AE source location. The proposed method was validated b...

the khorasan region is one of the active seismic zones in iranian plateau, which is located between central iran and kopet-dagh zones. we study the crustal thickness (h) and vp/vs ratio (k) in mashhad, capital of razavi khorasan province by the receiver function method. this study uses teleseismic events recorded by an array of three broadband stations of khorasan seismic network, earthquake re...

accurate measurements of physical characteristics of bone are essential for diagnosis, assessment of change following treatment, and therefore, indirectly, for evaluation of new forms of therapy. this is particularly true of osteoporosis and aging skeleton, in which fractures occur easily. methods: in this study an ultrasonic system was set-up and calibrated on plexiglas tubes of variable thick...

Seismic analyses of methane hydrate data from the Blake Outer Ridge indicate high Pwave velocity and anomalously low S-wave velocity in sediments containing methane hydrates. In an attempt to explain this observed P-wave and S-wave velocity structure at the transition from gas to hydrates, the effect of different hydrate models on elastic moduli and velocities are explored. After construction o...

in this paper the propagation of harmonic plane waves in a homogeneous anisotropic magneto-piezothermoelastic diffusive body with fractional order derivative is studied. the governing equations for a homogeneous transversely isotropic body in the context of the theory of thermoelasticity with diffusion given by sherief et al. [1] are considered as a special case. it is found that three types of...

BACKGROUND To investigate flow in the ductus venosus at 11-13 + 6 weeks of gestation in women with normal pregnancies in the Taiwanese population. METHODS Two hundred and fifty-two normal singleton pregnancies with gestational ages ranging from 11 to 13 + 6 weeks were examined in this study. The pulsatility index for veins (PIV), resistance index (RI), peak velocity during ventricular systole...

Shear wave velocity (Vs) data are key information for petrophysical, geophysical and geomechanical studies. Although compressional wave velocity (Vp) measurements exist in almost all wells, shear wave velocity is not recorded for most of elderly wells due to lack of technologic tools. Furthermore, measurement of shear wave velocity is to some extent costly. This study proposes a novel methodolo...

in this paper we are going to show the importance of mode identification in microtremor array analysis. the idea come from four concentric ambient noise array recordings with aperture 100 to 1000 meters, performed in southern urban area of tehran near the shrine of imam khomeini. these measurements were part of a comprehensive research project with the aim of determination of deep shear wave ve...