Seismic instruments: article

Аnnotation: To solve many geological and geophysical problems, in particular, the prediction of strong earthquakes, seismic zoning, and earthquake-resistant construction, it is necessary to have reliable data on the distribution of earthquake hypocenters in the study area. In turn, the completeness of data on the distribution of earthquake hypo-centers and the accuracy of their determination largely depend on the efficiency of the observation system. We evaluate the effectiveness of the actual network of seismological observations in Karelia, consisting of seven seismic stations. The effectiveness of the seismological observation network is estimated by the minimum magnitudes of seismic events recorded in the region under consideration and the minimum errors in determining the main parameters (time in the source and coordinates of the hypocenter) of the recorded events. The calculation of the minimum earthquake magnitudes for the Karelian seismological network shows that with station amplification of 30 thousand, the network is able to register earthquakes with a magnitude slightly less than 2, with a tendency to decrease this minimum magnitude, provided that the event is recorded by at least three stations. The errors in determining the coordinates of earthquake epicenters in latitude  (km) and in longitude  (km) do not exceed 1–2 km in the center of the network, and on the periphery of the network they are 6 and 11 km, respectively. The errors in determining the depths of earthquake sources H (km) by the system do not exceed 5 km in the vicinity of the stations and 25 km throughout the territory of Karelia.