An interface subduction earthquake of Mw 7.7 occurred on September 19, 2022, along the Middle America trench megathrust near the central Pacific coast of Mexico in the state of Michoacán. The LCI Research Program supported Principal Engineering Geologist Kevin Clahan to lead a joint geologic/geotechnical engineering reconnaissance effort between the Group of Advance Numerical Modeling and Instrumentation from the Institute of Engineering at National Autonomous University of México, GEOSIM-IIUNAM and Lettis Consultants International, Inc. The reconnaissance was organized and partially supported by the Geotechnical Extreme Events Reconnaissance Association, GEER, to collect perishable seismic, geological, and geotechnical data resulting from the September 19, 2022, earthquake. The reconnaissance involved geo-located observations over an 842 km path, with stops at key locations where earthquake effects were observed. These effects included structural damage, roadway and bridge damage, damage to a drainage culvert, and ground failure from liquefaction, lateral spreading, and landsliding.
https://geerassociation.org/components/com_geer_reports/geerfiles/2022%20Michoacan%20EQ.pdf