论文详情
采用曲线网格有限差分方法研究了瑞雷面波通过起伏地形时的传播特性。讨论了地形的凹凸、高(深)度、跨度等因素对面波波形、能量、频散等参数的影响。平缓地形对面波影响较小,而地形起伏较大时,则会产生严重的散射现象。地形起伏对面波有滤波效应,在频谱上会出现陷波点,陷波点频率随地形的高度与跨度变化。另外,曲线网格有限差分方法适应较复杂地形模型的地震波场数值模拟,可以应用于实际复杂地形的地震波场响应特征模拟与分析。
This study adopts the body-fitted grid finite-difference method to investigate Rayleigh wave propagation with undulating topography.Factors including concavity-convexity,height,and span of topography influence wave shape,energy,and frequency spectrum.It was found that when undulating topography changes smoothly,a Rayleigh wave can traverse the topography with no obvious distortion;conversely,strenuously undulating topography can result in clearly discernible frequency dispersion.It was found that undulating topography has a filtering effect on the frequency spectrum,which can cause a notch on the spectrum of the Rayleigh wave’s reflection/transmission,such that the notch frequency depends on the height/width of the topographic undulation.The curvilinear grid finite-difference method could be effectively applied to seismic modeling with undulating topography.
国家科技重大专项“大型油气田及煤层气开发及勘探评价-涪陵页岩气开发示范工程”(2016ZX05060-005)资助。