Aftershock Area Assessment Based on the First Aftershocks at the Khibiny Deposits

Abstract—This paper examines the construction of an aftershock activity area in conditions of natural and mining-induced seismicity based after the data on the first aftershocks. The study area is apatite–nepheline deposits located in the southern part of the Khibiny massif. A significant number of variants of aftershock regions were investigated that differ in shape, location, and orientation. The size of the area has been determined by scaling based on physical and statistical characteristics calculated from both the main shock and the first aftershocks. The criterion based on an error diagram has been used to quantitatively compare a large number of different variants. As a result, the optimal area type has been selected, which showing the best results of the quantitative test based on seismicity data on the study area for 1996–2022. The technique can be used to predict the area of aftershock activity distribution at the Khibiny massif deposits after a natural–mining-induced earthquake based on operational processing data.