The Structural Extreme Events Reconnaissance (StEER) Network has released its Preliminary Virtual Reconnaissance Report (PVRR) summarizing its findings on the impacts of the 23 June 2020 Mw 7.4 earthquake in Oaxaca, Mexico. The report was prepared by StEER’s Virtual Assessment Structural Team (VAST) and relies upon publicly available news reports, social media, and other resources. The PVRR can be accessed at https://aub.ie/steer_2020_oaxacamx_EQ and is curated on NHERI DesignSafe with full citation information as follows:

Miranda, E. Acosta Vera, A. Archbold, J. Arteta, C. Carrillo, J. Dávalos, H. Gunay, S. Gutierrez Soto, M. Hassan, W. Heresi, P. Messina, A. Miranda, S. Pajaro Miranda, C. Poulos, A. Robertson, I. Ruiz-García, J. Scagliotti, G. Kijewski-Correa, T. Mosalam, K. Prevatt, D. Roueche, D. (2020) "Preliminary Virtual Reconnaissance Report", in StEER - Crucecitas, Mexico Mw 7.4 Earthquake: Preliminary Virtual Reconnaissance Report (PVRR). DesignSafe-CI. https://doi.org/10.17603/ds2-k2bp-t724.

PVRR OVERVIEW: On June 23rd, 2020, at 10:29 am local time, a moment magnitude 7.4 earthquake struck near the towns of La Crucecita and Huatulco in the state of Oaxaca in Mexico. The State of Oaxaca is one of the poorest states in Mexico where approximately two-thirds of the population are below the poverty rate. The largest recorded peak ground acceleration was 0.44g recorded near Huatulco by one of the broadband stations of the Institute of Geophysics of the National Autonomous University of Mexico. Since 1991 Mexico operates an Early Warning System which for this event provided warning ranging from 30 seconds for the capital of Oaxaca located at approximately 170 km from the epicenter to almost 2 minutes for Mexico City located approximately 530 away from the epicenter. The earthquake produced 9 deaths, hundreds of injuries, damage to more than 2,000 residential buildings, damage to many commercial structures and damage to infrastructure including highways, bridges, hospitals, oil refineries.

The purpose of this Preliminary Virtual Reconnaissance Report is to provide a summary of the characteristics of this event, the seismicity of the regions and to provide a brief description of the main effects of the earthquake collected from publicly available information.

As the opportunity for new knowledge from damage to the built environment in this event was limited, and considering the constraints imposed by the ongoing COVID-19 epidemic, StEER does not plan to activate a Field Assessment Structural Team (FAST).