Abstract

In recent years three new problems emerged in aftershock physics. We shall refer to these problems in a preliminary way as the dynamic, the inverse, and the morphological problem. They have been distinctly stated, partially solved, and have a fundamental character. The dynamic problem consists in searching for the effect of a circumnavigating seismic echo that occurs after the main shock of an earthquake. According to theory, the convergent seismic surface wave due to a main shock returns to the epicenter about 3 h later and initiates the occurrence of a large aftershock. The results of our study corroborate this theory. The second problem consists in an adequate description of the average evolution of the aftershock process. We introduce a new quantity, a deactivation coefficient for an earthquake source. It describes the “cooling” of the source after the main shock, and we proposed an equation to describe aftershock evolution. We used the evolutionary equation to formulate and solve the inverse problem in earthquake source physics, resulting in an Atlas of Aftershocks, which demonstrates the diversity of ways for the evolution of the deactivation coefficient. The third fundamental problem consists in modeling the spatial and space–time distribution of aftershocks. The solution enhances our understanding of the structure and dynamics of an earthquake source. We also discuss in great detail some other interesting problems in aftershock physics.

中文翻译：

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余震物理学中的三个问题

摘要

近年来，余震物理学中出现了三个新问题。我们将这些问题初步地称为动力学，逆问题和形态问题。它们已被明确陈述，部分解决并具有基本特征。动态问题在于寻找在地震主震之后发生的绕行地震回波的影响。根据理论，由于主震而产生的会聚地震面波大约在3小时后返回震中，并引发大余震的发生。我们的研究结果证实了这一理论。第二个问题在于对余震过程平均演变的充分描述。我们引入了一个新的数量，即地震源的失活系数。它描述了主震后震源的“冷却”，并提出了一个方程来描述余震的演变。我们使用演化方程来公式化和解决地震震源物理学中的反问题，从而产生了余震图集，这证明了失活系数演化的方法多种多样。第三个基本问题在于对余震的时空分布进行建模。该解决方案加深了我们对地震源的结构和动力学的理解。我们还将详细讨论余震物理学中的其他一些有趣的问题。产生了余震图集，这证明了失活系数演化方式的多样性。第三个基本问题在于对余震的时空分布进行建模。该解决方案加深了我们对地震源的结构和动力学的理解。我们还将详细讨论余震物理学中的其他一些有趣的问题。产生了余震图集，这证明了失活系数演化方式的多样性。第三个基本问题在于对余震的时空分布进行建模。该解决方案加深了我们对地震源的结构和动力学的理解。我们还将详细讨论余震物理学中的其他一些有趣的问题。