Modern seismic sensors are capable of recording high precision vibration data continuously for several months. Seismic raw data consists of information regarding earthquake’s origin time, location, wave velocity, etc. Currently, these high volume data are gathered manually from each station for analysis. This process restricts us from obtaining high-resolution images in real-time. A new in-netw...

Seismic modeling is a foundation of geophysical date processing. A multisymplectic pseudospectral method for seismic modeling is presented in this paper. This method takes the multisymplectic structure of the scalar wave equation into account and possesses discrete multisymplectic conservation laws. Numerical experiments demonstrate the remarkable capability of this new method for long-time sim...

[1] A hybrid method is developed for calculating synthetic seismograms for seismic waves propagating in two-dimensional localized heterogeneous anisotropic media. The hybrid method is a combination of analytic and numerical methods, with the numerical method (finite difference, or FD) applied in the heterogeneous anisotropic region only and the analytic method (generalized ray theory, or GRT) o...

a r t i c l e i n f o a b s t r a c t Keywords: Wave equation with variable coefficients Heterogeneous media Accurate modeling of seismic wave Localized operator Suppression of numerical dispersion Studying seismic wavefields in the Earth's interior requires an accurate calculation of wave propagation using accurate and efficient numerical techniques. In this paper, we present an alternative me...

[1] We measure direction and amplitude of ocean-generated continuous seismic noise in the western United States. Slowness direction of the noise is determined using array beamforming, and particle motion direction from individual three-component stations. We find two surprising results. First, the noise is highly monodirectional at all sites, regardless of coastal distance. A single narrow gene...

We introduce a novel finite-difference (FD) approach for seismic wave extrapolation in time. We derive the coefficients of the finite-difference operator from a lowrank approximation of the space-wavenumber, wave-propagator matrix. Applying the technique of lowrank finite-differences, we also improve the finite difference scheme of the two-way Fourier finite differences (FFD). We call the new o...

We introduce a novel technique for seismic wave extrapolation in time. The technique involves cascading a Fourier Transform operator and a finite difference operator to form a chain operator: Fourier Finite Differences (FFD). We derive the FFD operator from a pseudo-analytical solution of the acoustic wave equation. 2-D synthetic examples demonstrate that the FFD operator can have high accuracy...

Defining the oceanic lithosphere as a thermal boundary layer allows to explain, to first order, age-dependent bathymetry and isotropic wave speeds. In contrast, SS precursors and receiver functions suggest a subhorizontal interface within this layer, on top of a radially anisotropic zone. Comparing a suite of geodynamic scenarios against surface wave dispersion data and seismic discontinuities,...

[1] Recent studies attribute land double-frequency (DF) microseism observations to deep water generation. Here we show that near-coastal generation is generally the dominant source region. This determination is based on observations at land and ocean seismic stations, buoys, gravity-wave hindcasts, and on beamforming results from continental seismic arrays. Interactions between opposing ocean w...

We use multi-channel analysis of surface waves (MASW) on seismic data in an attempt to test data acquisition parameters and compare those results to reaffirm existing general theoretical recommendations and rules of thumb. Of particular interest were optimum seismic receiver spread size, minimum and maximum receiver offsets and dominant geophone frequency for best-case fundamentalmode dispersio...