| Popis: |
The GIS-EEDB (the Expert Earthquake Database) and GIS-ENDDB (the Earth’s Natural Disasters DataBase) geoinformation systems implement methods for spatial-temporal analysis of both classical and new characteristics of the seismogeodynamic process. One of the new characteristics is a normalized creepex parameter that can be used in the statistical approach to studying of seismicity to assess a relative contribution of “soft” (creep) and “hard” (explosion) movements to the overall process of focal radiation. In this paper, the following modifications of the creepex parameter are proposed and compared: 1) Cr0 Cr0_world and CrN CrN world as the result of reducing the parameters Cr0 and CrN of each event to the world average values of the creepex, obtained from the polynomial dependence of Cri_world (i = 0, N) on MS_world where Cri_world are calculated based on the world average estimates of Ms_world and mb_world at uniform intervals of the seismic moment (NEIC catalog), 2) Cr_bji as the result of reducing CrN of each event to CrN_bji i.e. to the average for the studied in this work BJI catalog creepex values obtained from the polygonal trend CrN (MS) of all the catalog events. The advantage of using the creepex parameter, reduced to the trend of averaging the magnitudes of the catalog in question, is revealed, since the smallest linear dependence of the creepex on the magnitude is achieved (in comparison with the classical and normalized creepex) and the symmetry in the maximum amplitude of the deviation of the parameter relative to zero is preserved. Examples of the application of the compared parameters in specific seismic-geodynamic studies of aftershock processes of the Molucca and Simushir earthquakes also demonstrate the advantage of the parameter Cr_bji n the observed correspondence of the variations of the latter to the known physical processes in the focal zone of the Kashmir event, studied by the seismic-geodynamic methods of the GIS-EEDB geographical information system. |
