Abstract
A comprehensive data base of about 17000 historical and recent earthquakes has been established for the Central American region, based on existing research and reports from Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica and Panama. The catalog includes known damaging historic earthquakes, as well as the more important of the recent data, including both macroseismic and instrumental observations. The catalog starts in the beginning of the 16th century and is limited to macroseismic data (reeported phenomena and associated damage) until 1902, while it for the time since then contains both macroseismic and instrumental observations. Recent local network solutions are normally included only for events above magnitude 3.5.
The new catalog is considered to be reasonable complet for earthquakes with magnitudes MS ≥5.5 back to around year 1900, and for MS ≥7 back to around year 1820, and it should have the capabilities of further assisting the ongoing efforts towards a more reliable evaluation of the seismogenic potentials in the region.
The catalog infomation has been used in this paper for developing new relations between body wave magnitude mb and surface wave magnitude MS, between mb and local magnitude ML, and between MS and ML. New relations have also been developed between mb, MS and ML and maximum intensity Imax, between ML and felt radius, and between ML and felt area for intensity levels between III and VIII. Such relations are potentially important for a further development and improvement of the magnitude assessments for both newer and older earthquakes, as well as for many questions related to earthquake engineering.