Problems of Engineering Seismology: article

Аnnotation: Aftershocks following a large earthquake are inevitable part of preparation and occurrence of large earthquakes. Depending on the location of their epicenters, the tectonic-structural conditions of the epicentral zone and the earthquake intensity on the Earth's surface, aftershocks occupy different distributions and have a certain area. Establishing quantitative relationships between the aftershock area and the main parameters of an earthquake: magnitudes, rupture length, and the slip value can contribute to improving the model of an earthquake as a natural physical phenomenon. The sizes of aftershocks epicentersʹ areas and their deformations, as well as macroseismic changes on the Earth's surface, will indirectly indicate the strength of the main shock of the earthquake, as well as the presence of areas with different weakening of rocks in the epicentral zone. This paper proposes a method for the determination the size of the aftershocks epicentersʹ areas on the basis of a deformation model of preparation and origin of an earthquake previously proposed by the author. A new expression has been obtained for determining the area of epicenters depending on the length of the rupture formed during the earthquake and the value of the average slip at the rupture, as well as its logarithmic and linear dependence on the magnitude of the earthquake. It is shown that the areas of aftershocks and deformations around the focus are identical.