Preliminary catalog of aftershocks of the Guatemala earthquake of February 4, 1976, from the area between Guatemala City and Lake Atitlan

A six-station seismic network, about 140 km in diameter, has been operated just west of Guatemala City since March 1975, as part of a cooperative project between the U.S. Geological Survey and the Institute Nacional de Sismologia, Vulcanologia, Meteorologia e Hidrologia (INSIVUMEH), of Guatemala. The purpose of this project was to monitor the seismicity near the active volcanoes Pacaya and Fuego bait the seismic stations were well situated to record several thousand aftershocks from the magnitude 7.5 (Ms) Guatemalan earthquake of February 4, 1976. This catalog contains hypocentral data on 1560 of these events from selected time frames between February 5 and June 30, 1976.