Higher quality shear wave velocity has been pursuing since its importance in multicomponent exploration. To better monitoring CO2 sequestration, shear wave velocity (Vs) is needed to implement elastic numerical study on the target reservoir. A number of shear wave velocity estimation methods and their corresponding comprehensive comparison are presented in this article. The survey is situated i...

recordings of ambient noise or microtremors are increasingly used to find valuable information on soil in one dimension at a given site. ambient vibrations, which are assumed to be mainly composed of surface waves, can be used to determine the surface wave dispersion curve in order to retrieve shear wave velocity profile. in this regard, microtremors are usually recorded simultaneously in an ar...

In this paper, we introduce and evaluate a novel sonoelastographic technique for imaging shear velocity distributions from propagating shear wave interference patterns (termed crawling waves). A mathematical relationship between local crawling wave spatial phase derivates and shear velocity is presented with phase derivatives estimated using an autocorrelation-based technique. Results from homo...

Wave propagation is used as an advanced tool of determining elastic properties of rocks. In spite of being cheap and non destructive tests of rock mechanics, due to its modernity method is not yet replacing the traditional dear and destructive tests. In order to pave ways of replacing this test and making best use of it all effective factors of such method are to be assessed. One fundamental fa...

Ground motions recorded within sedimentary basins are variable over short distances. One important cause of the variability is that local soil properties are variable at all scales. Regional hazard maps developed for predicting site effects are generally derived from maps of surficial geology; however, recent studies have shown that mapped geologic units do not correlate well with the average s...

To establish a versatile means for screening and management of nonalcoholic steatohepatitis (NASH), shear wave velocity was measured in 20 normal controls and 138 consecutive nonalcoholic fatty liver disease (NAFLD) cases. Referencing biochemical properties in 679 healthy volunteers, a formula to distinguish NASH suspects was established and validated in another cohort of 138 histologically pro...

local site conditions have a strong effect on ground response during earthquakes. two important soil parameters that control the amplification effects of seismic motions by a soil column are the soil hysteretic damping ratio and shear wave velocity. this paper presents the results of in situ damping ratio measurements performed using continuous surface wave attenuation data at a site in semnan ...

Peripheral nerves are exposed to mechanical stress during movement. However the in vivo mechanical properties of nerves remain largely unexplored. The primary aim of this study was to characterize the effect of passive dorsiflexion on sciatic nerve shear wave velocity (an index of stiffness) when the knee was in 90° flexion (knee 90°) or extended (knee 180°). The secondary aim was to determine ...

We apply 2-D wave-equation prestack depth migration to a North Sea basalt dataset. High velocity and impedance contrasts across a basalt layer causes low P-wave reflection signal-to-noise ratio under the basalt. We first migrate the P-wave data with a provided depth velocity model, and then replace sub-basalt P-wave velocity with a simple estimate of shear wave velocity and migrate locally-conv...

one of the important problems in earthquake geotechnical engineering is liquefaction phenomenon that happens in loose saturated granular soils. in this study, 11 boreholes from govanjik and dayalar area in downstream of sattarkhan dam collected and evaluated. results of research are showed that with assuming cementation in soils, liquefaction potential is weak to moderate than non-cemented cond...