A P-SV hybrid method is developed for calculating synthetic seismograms involving two-dimensional localized heterogeneous structures. The finite difference technique is applied in the heterogeneous region and generalized ray theory solutions from a seismic source are used in the finite difference initiation process. The seismic motions, after interacting with the heterogeneous structures, are p...

S U M M A R Y Assessing the similarities of seismic attributes can help identify tremor, low signal-to-noise (S/N) signals and converted or reflected phases, in addition to diagnosing site noise and sensor misalignment in arrays. Polarization analysis is a widely accepted method for studying the orientation and directional characteristics of seismic phases via computed attributes, but similarit...

We present a method for estimating seismic attenuation based on frequency shift data. In most natural materials, seismic attenuation increases with frequency. The high-frequency components of the seismic signal are attenuated more rapidly than the low-frequency components as waves propagate. As a result, the centroid of the signal’s spectrum experiences a downshift during propagation. Under the...

[1] In complex tectonics regions, seismological, geophysical, and geodynamic modeling require accurate definition of the Moho geometry. Various active and passive seismic experiments performed in the central Mediterranean region revealed local information on the Moho depth, in some cases used to produce interpolated maps. In this paper, we present a new and original map of the 3‐D Moho geometry...

We describe a large-scale simulation of the seismic wave propagation from the 2011 Tohoku-Oki earthquake. We combine structure models for topography, sediments, crust and subducting plates to construct a 3D structure model for the northeastern Japan area. Then we simulate the near-field wave propagation by using a FDTD method which is accelerated by the use of multi-GPUs (Graphics Processing Un...

Iran is an active seismic region. Earthquake damage is commonly controlled by three interacting factors including source and path characteristics, local geological and geotechnical conditions and type of the structures. Obviously, all of this would require analysis and presentation of a large amount of geological, seismological and geotechnical data. In this paper, nonlinear geotechnical seismi...

Water storage tanks not designed explicitly for seismic loading could require retrofit. One of the common ways of retrofit include some structural change in the lateral load resisting system that could be expensive and requires the tank to be out of service for relatively long time. This paper introduces a novel method to reduce seismic demand on tank’s wall without structural intervention. Thi...

Abstract: This paper provides a new statistical approach to blind recovery of both earth signal and source wavelet given only the seismic traces using independent component analysis (ICA) by explicitly exploiting the sparsity of both the reflectivity sequence and the mixing matrix. Our proposed blind seismic deconvolution algorithm consists of three steps. Firstly, a transformation method that ...

On the basis of the optimization-based approach to the analysis of massive ordered data sets, a new method is proposed for computer-aided interpretation of seismic exploratory data from the so-called crystalline basement of the Earth mantle, which underlies the relatively thin sedimentary cover having been, up to now, the almost exceptional object of seismic explorations. The seismic explorator...

We calculate the vertical mass discharge rate from Mount St. Helens for the first few minutes of the May 18, 1980 cataclysmic eruption using a new method based on seismic constraints. The observed seismic waves indicate that the seismic source is a series of single forces. We model these forces as thrusts due to a combination of the momentum flux of the erupted products and the pressure of the ...