SphGLLTools: A toolbox for visualization of large seismic model files based on 3D spectral-element meshes
SphGLLTools: A toolbox for visualization of large seismic model files based on 3D spectral-element meshes
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DOI：
10.1016/j.cageo.2021.105007
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发表时间：
2021-12-29
影响因子：
4.4
通讯作者：
van der Lee, Suzan
中科院分区：
文献类型：
--
作者：
Ciardelli, Caio;Bozdag, Ebru;van der Lee, Suzan
伴随层析成像是一种基于三维波动模拟的全波形反演技术，它利用了计算能力和数值方法的进步，已成为被动源地震学中常用的工具。从全球到储层尺度，地震模型可以通过从全地震波形提取信息在伴随反演中迭代更新。地震模型通常在用于波浪模拟的数值网格上构建。因此，模型文件的大小取决于在由数值网格控制的模拟中实现的最小可分辨周期（网格分辨率越高，模型和网格文件越大）。这是最近的全球规模的伴随断层模型的数值网格的大小和格式提出了挑战，模型可视化，分析，解释和共享模型文件，这是一个具体的问题。在这里，我们提出了SphGLLTools，一个开源工具箱，旨在通过将全球伴随模型扩展到球谐函数来减少这些挑战，球谐函数广泛用于全球地震学。我们的工具最初设计用于最近的全球伴随层析成像研究中使用的谱元网格。SphGLLTools方便了许多常见的模型可视化和分析任务，包括在谱元网格上采样的模型的球谐展开以及用于轻松共享、可视化和解释大规模地震模型文件的相关工具。所有开发的例程都附有用户说明，并可通过GitHub获得。出于透明性、再现性和教育目的，我们还提供了Colab笔记本，直观而全面地回顾了谱元网格、球谐展开和其他模型分析工具的原理和方法。
Adjoint tomography, a full-waveform inversion technique based on 3D wave simulations, has become a commonly used tool in passive-source seismology, drawing on advances in computational power and numerical methods. From global to reservoir scales, seismic models can iteratively be updated in adjoint inversions by extracting information from full seismic waveforms. Seismic models are typically constructed on the numerical mesh used for wave simulations. Thus the size of model files depends on the minimum resolvable period achieved in simulations controlled by the numerical mesh (the higher the mesh resolution, the larger the model and mesh files). This is specifically a concern for recent global-scale adjoint tomographic models where the size and format of numerical meshes pose challenges for model visualization, analysis, interpretation, and sharing model files. Here, we present SphGLLTools, an open-source toolbox that intends to diminish these challenges by expanding global adjoint models onto spherical harmonic functions, which are widely used in global seismology. Our tools are initially designed for spectral-element meshes used in recent global adjoint tomography studies. SphGLLTools facilitate many commonplace tasks for model visualization and analysis, including spherical harmonic expansion of models sampled on spectral-element meshes together with associated tools for easy sharing, visualization, and interpretation of large-scale seismic model files. All the developed routines are accompanied by user instructions and are available through GitHub. For transparency, reproducibility, and educational purposes, we also include Colab notebooks, which provide an intuitive and comprehensive review of the principles and methods for spectral-element meshes, spherical harmonic expansion, and other model analysis tools.