Improving the technology of collecting and processing information on regional seismicity in the south of the East European platform

Abstract

Introduction: the seismicity analysis of the southern part of the East European platform for the instrumental period is presented (~25 years). Previously conducted assessment of the network sensitivity in the south of the East European platform showed that the network does not allow reliable registration of events with M~2.8 (M – calculated magnitude). Earthquakes are recorded by a sparse network of seismic stations and do not fully reflect the seismic conditions of the south of the East European platform. The network consists of 3-component stations, most of which have a high level of seismic noise. A large contribution to the registration of events of various nature in the study area is made by the small-aperture seismic array "Mikhnevo" (Institute of Geosphere Dynamics). Modern promising areas of studying seismicity in the southern part of the East European platform are considered. An example of using the AKASG seismic array data is given.

Research area: the territory of the southern part of the East European platform is classified as moderate tectonic activity. One of the latest perceptible earthquakes occurred on February 1, 2025 at 16h21m18s with mb=3.6 (mb – magnitude of the body P-wave) between the settlements of Poltava and Reshetilovka. Coordinates φ=49.59º N, λ=34.26º E, focal depth h=3 km.

Collection and processing method: processing of seismic data of the study area consists of the following points − automatic processing, interactive bulletin, processing of seismic arrays. The NDC in BOX software package developed by the Comprehensive Nuclear-Test-Ban Treaty Organization is used, including SeisComp, Geotool, GPMCC. An example of processing and interpretation of the earthquake of February 1, 2025 is given, a comparison of the main parameters of this earthquake, determined by various methods, International and regional seismological centers is carried out. An analysis of three seismic events that occurred in the Poltava region was conducted, and the features and differences of spectrograms of earthquakes with epicenters on different sides of the Dnieper-Donets aulacogen were considered.

Conclusions: the territory of the southern part of the East European platform is not seismically passive. Over the past 25 years, more than a dozen significant earthquakes have been recorded. In areas with weak seismicity, it is advisable to use seismic arrays. This will allow a more detailed study of the seismic regime.