Shallow earthquakes in the depth range 0–30 km make up more than 60% of all world's earthquakes. However, resolving their seismic source parameters such as the depth and moment tensor components presents a challenge. Here, we investigate the effect of frequencies higher than 0.025 Hz on centroid‐moment‐tensor inversion for the earthquakes occurring in the top 10 km of the Earth's crust. For a synthetic source located at the depth of 1 km, the maximum amplitude of ground motion due to a vertical dip‐slip mechanism from the waveforms filtered at 0.01–0.15 Hz is about 1,400 times larger than that filtered at 0.01–0.025 Hz. We quantify the effect of this dramatic difference and other waveform differences by introducing the “balance of amplitudes” and “waveform similarity” functions for different depths and frequencies. They present a simple and fast way to estimate the resolvability of seismic sources at a given depth and frequency band. For the 20 May 2016, M_w = 5.9 Petermann Ranges earthquake in Central Australia analyzed at 0.01–0.025 Hz, a high uncertainty accompanies the estimated source parameters. When the frequency band is 0.01–0.15 Hz, the centroid depth is well constrained at 1 km and the mechanism is a thrust fault striking ~314°N and dipping ~30°NE. These simulations require accurate Earth models. Our result, obtained at higher frequencies, is in a great agreement with various other studies that have been carried out for this earthquake and confirms a 20‐km long, shallow rupture.

中文翻译：

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浅震源质心矩张量的可分辨性及高频波形建模的改进

0至30公里深度范围内的浅地震占世界地震总量的60％以上。但是，解析其震源参数（例如深度和矩张量分量）提出了挑战。在这里，我们研究了高于0.025 Hz的频率对地壳顶部10 km发生的地震的质心矩张量反转的影响。对于位于1 km深度的合成源，在0.01–0.15 Hz处滤波的波形中，由于垂直倾滑机制引起的地面运动的最大振幅大约是在0.01–0.025 Hz处滤波的振幅的1400倍。通过引入针对不同深度和频率的“振幅平衡”和“波形相似性”功能，我们可以量化这种巨大差异和其他波形差异的影响。他们提出了一种简单快速的方法来估算给定深度和频带下地震源的可分辨性。对于2016年5月20日，M_w  = 5.9澳大利亚中部的Petermann Ranges地震在0.01–0.025 Hz进行分析，估计震源参数伴随高度不确定性。当频带为0.01–0.15 Hz时，质心深度被很好地限制在1 km处，其机理是推力断层撞击〜314°N且浸入〜30°NE。这些模拟需要准确的地球模型。我们在较高频率下获得的结果与针对该地震所做的各种其他研究非常吻合，证实了20 km长的浅层破裂。