Automated procedure for point and kinematic source inversion at regional distances
Automated procedure for point and kinematic source inversion at regional distances
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DOI：
10.1029/2009jb006450
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发表时间：
2010-06
影响因子：
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通讯作者：
S. Cesca;S. Heimann;K. Stammler;T. Dahm
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文献类型：
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作者：
S. Cesca;S. Heimann;K. Stammler;T. Dahm
[1]在过去的几年和几十年里，令人信服地建立了快速，自动程序的开发，用于检索中到大地震的点源参数，提供了越来越多的震源机制解。最初的应用程序在1000公里的距离上，后来又相继出现了区域数据集的具体程序。这些方法中的大多数是基于低通时间轨迹的拟合。我们在这里提出了一种新的技术，自动检索点源参数和高度参数化的运动破裂模型在区域距离，假设最近提出的程函模型来描述扩展源。在我们的方法中，我们使用更大的信息集，以更好地约束源参数，包括在不同的相位和频率范围内的振幅谱和位移的拟合。由于实施了绿色函数数据库，反演过程的时间消耗得到显著改善。我们采用了多步反演的方法，最终提供了震源机制，震级和质心位置的点源。对于震级高于Mw 5.5阈值的事件，可以另外检索震源几何形状、破裂延伸和平均滑动。我们讨论的方法和反演的稳定性，在两个案例领域显着地震的应用。我们关注德国和希腊及其邻近地区，考虑过去5年的主要浅源地震。所提出的方法是目前实施的自动数据处理在联邦地球科学和自然资源研究所在德国的地震观测。
[1] The development of fast, automatic routines for the retrieval of point source parameters of medium to large earthquakes was convincingly established in the last years and decades, providing an increasing number of focal mechanism solutions. Original applications at teleseismic distances have been successively accompanied by specific routines for regional data sets. The majority of these methods are based on the fit of low-passed time traces. We present here a new technique for the automatic retrieval of point source parameters and highly parameterized kinematic rupture models at regional distances, assuming the recently proposed eikonal model to describe the extended source. In our approach we use a larger set of information to better constrain the source parameters, including the fit of amplitude spectra and displacements at different phases and frequency ranges. The time consumption of the inversion process is significantly improved, thanks to the implementation of Green's functions databases. We adopt a multistep inversion approach, finally providing the focal mechanism, magnitude, and centroid location of the point source. For events with magnitude higher than a threshold of Mw 5.5, source geometry, rupture extension, and average slip may be additionally retrieved. We discuss the methodology and the inversion stability, showing applications to significant earthquakes in two case areas. We focus on Germany and Greece, and their neighboring areas, considering major shallow earthquakes in the last 5 years. The proposed method is currently implemented for automatic data processing at the Seismological Observatory of the Federal Institute for Geosciences and Natural Resources in Germany.