Permanent GPS Network


In general the activity of the Department consists in performing of earthquake observations on the territory of the country and in fulfilling of scientific research on the main themes mentioned in the paragraph of department structure – Monitoring and analysis of the seismicity in Bulgaria and neighboring lands, Macroseismic classification of the earthquake consequences, Seismic zoning of Bulgaria, Physics of seismic waves and earthquake sources, Earth’s crust and upper mantle structure in tectonically active regions, Some aspects of earthquake prediction, etc. The research activities on the themes mentioned above are performed by the staff of 54 persons, working at the Geophysical Institute in Sofia as well as at seismic stations of the modern National Seismological Network (NSN).

Equip of seismologists on duty is available 24 hours each day in NSN which is in charge to ensure permanent high-quality recording and analysis of the seismic signals, determination of the earthquake parameters, relevant assessment of the potential dangerous impact on the people or buildings and to inform the responsible governmental bodies if this impact becomes dangerous. In a case of a strong earthquake on the Balkans, the seismologist on duty sends Bulgarian seismic data to the neighboring and international seismological centers. At the same time the seismological team is responsible for the processing, analyzing and classification the daily seismological data.

The present-day highest level of modernization of NSN can be considered the main achievement of the Geophysical Institute in the field of Seismology. Other essential achievements are: Seismic zoning maps for various return periods – for the basis of the National Building Code; System for assessment of the earthquake consequences; Comprehensive historical and present-day earthquake catalogues for Bulgaria; Detailed macroseismic files, maps and atlases published in a series of monographs and papers; Theoretical and applied investigations in the field of space-time distribution and magnitude classification of earthquakes, source models, crust and upper mantle structure; Geodynamic models on the basis of focal mechanisms; Initial results on some prognostic anomalies of electro-magnetic, ionospheric or lithospheric nature.

The operative activities in the Seismological centre of NSN during felt earthquakes are objects of special attention – interviews during some extreme situation after felt stronger earthquake are usual practice for many mass media organizations.