AxiSEM: broadband 3-D seismic wavefields in axisymmetric media
نویسندگان
چکیده
We present a methodology to compute 3-D global seismic wavefields for realistic earthquake sources in viscoelastic anisotropic media, covering applications across the observable seismic frequency band with moderate computational resources. This is accommodated by mandating axisymmetric background models that allow for a multipole expansion such that only a 2-D computational domain is needed, whereas the azimuthal third dimension is computed analytically on the fly. This dimensional collapse opens doors for storing space–time wavefields on disk that can be used to compute Fréchet sensitivity kernels for waveform tomography. We use the corresponding publicly available AxiSEM (www.axisem.info) open-source spectral-element code, demonstrate its excellent scalability on supercomputers, a diverse range of applications ranging from normal modes to small-scale lowermost mantle structures, tomographic models, and comparison with observed data, and discuss further avenues to pursue with this methodology.
منابع مشابه
Seismic scalar wave equation with variable coefficients modeling by a new convolutional differentiator
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...
متن کاملInstaseis: instant global seismograms based on a broadband waveform database
We present a new method and implementation (Instaseis) to store global Green’s functions in a database which allows for near-instantaneous (on the order of milliseconds) extraction of arbitrary seismograms. Using the axisymmetric spectral element method (AxiSEM), the generation of these databases, based on reciprocity of the Green’s functions, is very efficient and is approximately half as expe...
متن کاملQuasi-cylindrical 2.5D wave modeling for large-scale seismic surveys
[1] The most common form of seismic exploration remains a nearly linear survey with data acquisition lines including the source and receivers. The interpretation of amplitude and waveform information for such linear acquisition requires consideration of 3D seismic wavefields. In many scenarios the structure is approximately 2D, but still modeling is needed for point sources. In recent years 2.5...
متن کاملA comparative review of wavefield tomography methods
Waveform inversion and wave-equation migration velocity analysis share one common feature: both techniques exploit information available in the same source and receiver wavefields reconstructed at all times and at all locations in space. These two wavefields are reconstructed from the same source function and observed data as solutions to the same wave-equation. Both techniques invert for the s...
متن کاملStereographic imaging condition for wave-equation migration
Single-scattering imaging consists of two steps: wavefield extrapolation, whose goal is to reconstruct source and receiver wavefields from recorded data, and an imaging, whose goal is to extract from the extrapolated wavefields the locations where reflectors occur. Conventionally, the imaging condition indicates the presence of reflectors when the propagation time of reflections in the source a...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2014