Investigation of the earth's crustal structure using earthquake and deep seismic sounding data obtained for the Carpathians

The joint analysis performed for the Carpathian region from seismological data (three-dimensional fields of velocities, areas of concentration of earthquake foci in the Vrancea focal zone) and interpretation of DSS data and those of other geophysical fields have permitted to obtain new evidence for the earth's crust and mantle structure in this region.     

Determination of the homogeneous magnitude system magnitudes in seismological practice

Routine determination of network magnitudes by means of the Eurasian homogeneous magnitude system (HMS) is described and tested on a selection of recent shallow earthquakes. The HMS earthquake magnitudes appear to be more accurate and more reliable than the conventional earthquake magnitudes used in the present seismological practice. A preliminary investigation of correlations between magnitudes determined from different wave types shows a possible dependence of the correlation on the type of focal mechanism of earthquakes.     

Determination of magnitude station corrections for a continental network of seismic stations

Summary A method for determining magnitude station corrections in a network of continental dimensions has been developed and tested for PV waves observed by eight selected Eurasian stations. Regional effects, observed for several stations, were taken into account. It appeared that station corrections could attain considerable values. The application of station corrections diminished both the dispersion of individual magnitude values and standard errors of mean network magnitudes.     

Optimisation of amplitude curves of seismic P-, S- and L-waves in the homogeneous magnitude system of the Eurasian continent

Amplitude curves for seismic P-, S- and L-waves have been constructed on the basis of the homogeneous magnitude system of the Eurasian continent. The optimum amplitude curves are compared with the standard amplitude curves used in seismological practice.