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引起新马德里地震活动的断层系曾在公元900±100年、公元1450±150年以及公元1811～1812年引发了在短期内成丛的大地震。由于测定液化特征年代的不确定性,新马德里过去这3次事件的时间间隔,可以短至200年和长达800年,平均500年。在理解新马德里地震带晚全新世历史及相应的断层系的现代构造运动方面所取得的这一进展,是通过对遍布于新马德里地区250多个场点的数百个地震引起的液化特征的研究而得到的。我们已经发现的证据表明,史前的喷砂与1811～1812年地震期间形成的一样,可能是在时间上密集成丛的或地震序列的多次地震所产生的复合结构。由喷砂的空间分布、大小以及它们的沉积单元,我们对每一地震序列中的地震推断震源区并估计震级,并由此描述断层系的详细行为特征。表明断层破裂是复杂的,地震带的中心分支于公元900年、公元1450年以及1811～1812年都发生过非常大的地震。根据200年的最小复发率,我们现在正在进入一个下一次1811～1812年类型的事件可能发生的时期。
The faulting that triggered the New Madrid Earthquake triggered earthquakes that plunged in the short term in 900 ± 100 years, 1450 ± 150 years and 1811-1812 AD. Due to the uncertainty of the age of liquefaction measurement, the intervals between the three New Madrid past events can be as short as 200 years and as long as 800 years, an average of 500 years. The progress made in understanding the late Holocene history of the New Madrid Seismic Belt and the corresponding tectonic movement of the modern tectonic movement was achieved through the liquefaction characteristics of hundreds of earthquakes scattered throughout the New Madrid area Research and get. The evidence we have found shows that prehistoric sandblasting, like that formed during the 1811-1812 earthquake, may be a composite structure created by multiple earthquakes in time or in seismic sequences. From the spatial distribution of blasting, its size, and their sedimentary units, we infer the source regions for earthquakes in each earthquake sequence and estimate the magnitudes of the earthquakes and describe the detailed behavior of the fault systems. It shows that the fault rupture is complicated. The center of the seismic belt is bounded by 900 AD. Very large earthquakes occurred in 1450 and 1811-1812. Based on the 200-year minimum relapse rate, we are now entering a period where the next type of events of 1811-1812 may occur.