资源环境科技发展态势分析平台

Resonances within a sedimentary basin result in complex local seismograms. To accurately calculate complex seismograms in numerical simulations, a fine grid discretization of the basin is required. However, due to the corresponding computational expense, high-resolution simulations of realistic earthquakes with a sedimentary basin are scarce. Here, with the China's most powerful supercomputer, Sunway TaihuLight, we simulate the strong ground motion of the 1976 Tangshan earthquake with a 3-D sedimentary basin at different spatial resolutions. We find that simulations with a coarse grid not only lose high-frequency information but also distort low-frequency waveforms in locations characterized by a complex basin geometry and conflict with the traditional viewpoint that coarse-grid simulations can resolve low-frequency information. Our work emphasizes the importance of large-scale, high-resolution seismic wave simulations in complex situations.