we usewe use ml shear wave velocity to derive a high resolution 2d ml shear wave velocity map for the iranian plateau. the ml amplitudes and arrival times are routinely measured for the calculation of local magnitude. ml shear wave velocity is very sensitive to the lateral change of crustal thickness and switches between the velocity of lg and sn waves. an lg wave will die out as soon as encoun...

The use of the shear wave velocity data as a field index for evaluating the liquefaction potential of sands is receiving increased attention because both shear wave velocity and liquefaction resistance are similarly influenced by many of the same factors such as void ratio, state of stress, stress history and geologic age. In this paper, the potential of support vector machines (SVM) based clas...

tehran, the capital of iran, is under the threat of large magnitude earthquakes (above 7) located on known active faults. previous studies on the effect of local surface geology on earthquake ground motion using 1d calculation of sh transfer function (jafari et al., 2001; jica & cest, 2000) and using experimental methods (haghshenas, 2005) based on earthquake and ambient noise vibration recordi...

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...

optimization of reservoir parameters is an important issue in petroleum exploration and production. the ant colony optimization(aco) is a recent approach to solve discrete and continuous optimization problems. in this paper, the ant colony optimization is usedas an intelligent tool to estimate reservoir rock properties. the methodology is illustrated by using a case study on shear wave velocity...

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...

Shear wave velocity (Vs) is known as one of the fundamental material parameters which is useful in dynamic analysis. It is especially used to determine the dynamic shear modulus of the soil layers. Nowadays, several empirical equations have been presented to estimate the shear wave velocity based on the results from Standard Penetration Test (SPT) and soil type. Most of these equations result i...

We use multi-channel analysis of surface waves (MASW) on seismic data to assess the practical impact of the assumed compressional-velocity and density parameters on the inverted shear-wave velocity results. The practical secondary-parameter impact evaluation was performed on data acquired in the arctic. The ice-sheet compressional-, shear-wave velocity and density variations with depth were ava...

Direct determination of formation shear wave travel time is impossible in "slow" formations where the shear wave velocity is lower than the borehole fluid (mud) velocity. However, the Stoneley waves in these formations are very sensitive to changes in formation shear wave properties and can be used to indirectly determine the formation shear velocity, In addition, the P wave packet is highly de...

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...