T-wave generation and propagation: a comparison between data and spectral element modeling.
T-wave generation and propagation: a comparison between data and spectral element modeling.
复制标题
T 波的产生和传播：数据和频谱元素建模之间的比较。
DOI：
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发表时间：
2013
影响因子：
2.4
通讯作者：
J. Royer
中科院分区：
文献类型：
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作者：
Guillaume Jamet;C. Guennou;L. Guillon;C. Mazoyer;J. Royer
T波是由地震产生的水下声波。它们的产生和传播的建模是一个具有挑战性的问题。使用谱元程序SPECFEM 2D，本文提出了第一个现实的模拟T波考虑到这种现象的主要方面：源的辐射模式，地震波在地壳中的传播，在非平面海底的地震声转换，以及声波在水柱中的传播。模拟信号进行比较，从大西洋中脊记录的水听器阵列的数据。地壳/水界面由海底测深确定。测试了水声速剖面和海底地震速度的不同组合以及源的频率内容。模拟的T相的相对振幅、主要到达时间和持续时间与观测数据吻合良好;频谱图和早期到达的差异可能是由于过于简单的源信号和环境模型。这些例子证明了SPECFEM 2D程序模拟地震产生的T波的能力。
T-waves are underwater acoustic waves generated by earthquakes. Modeling of their generation and propagation is a challenging problem. Using a spectral element code-SPECFEM2D, this paper presents the first realistic simulations of T-waves taking into account major aspects of this phenomenon: The radiation pattern of the source, the propagation of seismic waves in the crust, the seismic to acoustic conversion on a non-planar seafloor, and the propagation of acoustic waves in the water column. The simulated signals are compared with data from the mid-Atlantic Ridge recorded by an array of hydrophones. The crust/water interface is defined by the seafloor bathymetry. Different combinations of water sound-speed profiles and sub-seafloor seismic velocities, and frequency content of the source are tested. The relative amplitudes, main arrival-times, and durations of simulated T-phases are in good agreement with the observed data; differences in the spectrograms and early arrivals are likely due to too simplistic source signals and environmental model. These examples demonstrate the abilities of the SPECFEM2D code for modeling earthquake generated T-waves.