A novel time-domain viscoacoustic wave equation and its numerical simulation
Luo Wenshan1,2, Chen Hanming3, Wang Chengxiang2, Zhou Hui3, Wang Shihu2
1. Chengdu University of Technology (CDUT), Chengdu, Sichuan 610059, China;
2. Research and Development Center, BGP Inc., CNPC, Zhuozhou, Hebei 072751, China;
3. State Key Laboratory of Petroleum Resources and Prospecting, CNPC Key Lab of Geophysical Exploration, China University of Petroleum (Beijing), Beijing 102249, China
Abstract：We develop a fractional Laplacian viscoacoustic wave equation based on the dispersion relation of the constant-Q model, and formulate the wave equation into the first-order velocity-pressure system. Compared with the existing velocity-pressure-strain formulation, our formulation is more compact, and saves memory storage after discretization. The staggered-grid pseudo-spectral (SGPS) method is adopted to numerically solve our viscoacoustic wave equation. The convolutional perfectly matched layer (CPML) is applied to suppress artificial edge reflections in numerical simulation. Test results demonstrate that numerical simulation of our viscoacoustic wave can correctly describe seismic wave attenuation and dispersion. The SGPS approach combined with the CPML is verified to be an efficient numerical simulation scheme.
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