Processed Strong-Motion Records from the Limón, Costa Rica Earthquake of 22 April 1991

Abstract

Strong-motion records were recovered from 15 accelerographs at 14 stations operated by the Strong Motion Instrumentation Program of the Earthquake Engineering Laboratory (EEL) at the University of Costa Rica (Santana and others, 1991) following the damaging Limón, Costa Rica earthquake of April 22, 1991. The sites range in epicentral distance from 73 to 160 km; peak horizontal accelerations at ground level ranged from 0.03 to 0.27 g. The accelerograms are characterized by long duration of strong shaking, of approximately 30 seconds.

An extensive strong motion data set from a moment magnitude (Mw) 7.5 earthquake is rare. Because of the importance of these data not only to Costa Rica but also to California, the California Strong Motion Instrumentation Program (CSMIP), in cooperation with the University of Costa Rica, digitized and processed these data for distribution to engineers, seismologists and others concerned with the seismic safety problem. This processed data is the second extensive set of data from an earthquake with magnitude between the magnitude 7 Lorna Prieta earthquake and the magnitude 7.8 Chile and Tabas, Iran earthquakes.