Russo, R. M., C. R. Bina, W. P. Richardson, A. Montilla, J. Avedaño, E. Gajardo, M. Schmitz, and H. Rendon, Field seismic study of the July 9, 1997 Cariaco, Venezuela, earthquake, Eos, Transactions of the American Geophysical Union, 28, Fall Supplement, F447, 1997.
We deployed nine seismic stations in and around the region of the July 9, 1997 Cariaco earthquake in NE Venezuela in order to study aftershocks of this large and damaging earthquake. The event, magnitude Mw = 6.9, caused over 80 deaths in the towns of Cariaco, Cumana, and Casanay, and material damage was extensive (e.g., 75% of buildings in Cariaco destroyed). Our array consisted of seven short period three component seismometers (Mark Products L-22) and two broadband three component sensors (Streckeisen STS-2). Concurrent deployments by the Centro de Sismologia, the Universidad de Oriente (5 permanent and 2 temporary stations), FUNVISIS (3 sites), Universidad de Chile (6 stations), and the GeoForschungsZentrum Potsdam (19 sites) raised the total number of seismometers deployed to study the event aftershocks to 46. The July 9, 1997 main shock ruptured ground surface over an area extending from San Antonio del Golfo in the west to Casanay in the east. The surface rupture revealed 25 cm of dextral slip on an E-W striking segment of the El Pilar Fault. The surface rupture is consistent with the preliminary centroid moment tensor focal mechanism determined by Harvard University, which is nearly pure dextral strike-slip on a steeply N-dipping, E-striking fault plane. We will present preliminary analyses of the main shock and aftershock sequence.Copyright © 1997 American Geophysical Union