Completeness periods for the declustered catalog were estimated for the definition of appropriate seismic source models for the whole territory. Different magnitude-conversion relationships, compatible with available local and regional ones, has been established to obtain unified moment magnitude estimates for the whole catalog. Large earthquake events (M W ≥ 6.5) have been carefully revised for their epicentral locations and magnitudes from trusted publications. Earthquake and focal mechanism data have been compiled from various local, regional and international sources. The details about the catalog compilation, the removal of duplicate events, unifying the magnitude scales, removal of dependent events through the declustering process and its completeness analysis are presented. Here we present a new updated and unified Poissonian earthquake catalog for Mexico. with all available details is uploaded in the website. A list of 203,448 earthquakes (including aftershocks and foreshocks) occurred in the region covering the period from 250 B.C. A significant decrease in seismic b value was seen when declustered catalog was used which illustrates that a larger proportion of dependent events in the earthquake catalog are related to lower magnitude events. The study area was divided into 2,025 grid points (1°×1°) and the spatial variation of the seismicity across the region have been analyzed considering all the events within 300 km radius from each grid point. The dependent events (75.3%) in the raw catalog have been removed and the effect of aftershocks on the variation of b value has been quantified. Region-specific earthquake magnitude scaling relations correlating different magnitude scales were achieved to develop a homogenous earthquake catalog for the region in unified moment magnitude scale. Both historical and instrumental data were compiled and the complete catalog of Indian earthquakes till 2010 has been prepared. An attempt has been made to quantify the variability in the seismic activity rate across the whole of India and adjoining areas (0–45°N and 60–105☎) using earthquake database compiled from various sources.
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