Seismicity of the State of Puebla, Mexico, 1986-1989

Abstract

The seismic activity in the State of Puebla, Mexico and its surroundings, between January 1986 and August 1989, is discussed using data from the seismic network of the University of Puebla. The hypocentral locations were obtained using the programs HYP071PC and HYPOCENT. The calculated theoretical errors using the program HYPOERR coincide with the estimated errors from the location procedure. A total of 350 earthquakes were located with rms less to 2. Most of the hypocenters are at depths less than 50 km, with the exception of the southern region, where events deeper than 50 km are found. These deeper events are probably associated with the contact between the oceanic and continental lithospheres, which correspond to the Cocos and North American plates. 92% of the events have coda magnitude between 2 and 4, although events with magnitudes greater than 7 have occurred in this region.