LOCAL SEISMOLOGY. PAS METHOD OF THE SEISMOGRAMS PAREWISE ANALYSIS. BASE TABLE OF THE DAGESTAN SEISMIC STATIONS NETWORK
The use of the PAS Method – Pairwise Analysis of Seismograms – allows directly, using only data recorded at two seismic records to determine: a) the origin time, for a mathematically precise correction of the earthquake, b) the ratio of the distances from the source to the pair stations, to locate the source, c) the ratio of the velocities that allows controlling of the elastic properties of the medium.This paper analyzes the main disadvantages of the traditional processing hodograph gathers and presents the principles of the method of PAS, practically tested for near earthquakes. At the end the table of distances between base stations and azimuths determining the orientation of the segments in both directions is given with formulas for calculating these tables.