Recently, a decoupled fractional Laplacian viscoacoustic wave equation has been developed based on the constant-Q model (CQM) for describing wave propagation in heterogeneous media. However, the fractional orders depend on seismic quality factor (Q), and thus are spatially varying. The spatial variable fractional-order Laplacian wave equation is intractable to numerical calculation. To facilitate numerical simulation, we transform the variable fractional-order Laplacian wave equation into a constant fractional-order Laplacian wave equation. The fractional orders in our viscoacoustic wave equation are independent of the spatially varying Q. The fast Fourier transform (FFT) is applied to calculate the fractional Laplacians to avoid spatial dispersion. Numerical examples verify that our constant fractional-order Laplacian viscoacoustic wave equation has almost the same accuracy as the existing spatial variable fractional-order Laplacian wave equation in describing the constant-Q dispersion and attenuation.
Presentation Date: Thursday, October 20, 2016
Start Time: 8:30:00 AM
Presentation Type: ORAL