Although small earthquakes are expected to produce weak shaking, ground motion is highly variable and there are outlier earthquakes that generate more shaking than expected—sometimes significantly more. We explore datasets of M 0.5–8.3 earthquakes to determine the relative impact of frequent, smaller‐magnitude earthquakes that rarely produce strong ground motion, to rare, large earthquakes that always cause strong shaking. We find that the natural variability of ground motion, combined with the Gutenberg–Richter magnitude–frequency relationship, ensures that most occurrences of any ground motion come from earthquakes of smaller magnitude than expected, often >2 magnitude units smaller. This holds even for very strong shaking (⁠>20%g⁠), suggesting that M<7 earthquakes could be a significant source of damage.

中文翻译：

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震动几乎总是一个惊喜：产生重大地面运动的地震

尽管预计小地震会产生微弱的震动，但地震动变化很大，并且离群地震会产生比预期更多的震动，有时甚至更多。我们探索了0.5-8.3 M级地震的数据集，以确定很少产生强地震动的频繁，小震级与总是引起强烈震动的罕见大地震的相对影响。我们发现，地震动的自然可变性与古登堡-里希特震级-频率关系结合在一起，可以确保大多数地震动的发生都比预期的震级小，通常大于2个震级单位。即使是非常强烈的震动也是如此（⁠> 20％g⁠），这表明M <7地震可能是重要的破坏源。