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At 18:08 on August 4, 2020, a large explosion occurred at Hangar 12 in the Port of Beirut. The size of the explosion was equivalent to that of an earthquake with a local magnitude (ML) of 3.3 according to the USGS. As one of the largest nonmilitary explosions to ever impact an urban region, this event provides unprecedented opportunities to document explosion impacts on urban infrastructure. To facilitate this data collection, the Geotechnical Extreme Events Reconnaissance (GEER) Association coordinated a multiagency response directed toward the collection of perishable data of engineering interest. Two main categories of infrastructure systems were impacted: the Port of Beirut and the Beirut building stock. Within the Port, the explosion triggered a quay wall failure and flow slide, and strongly impacted grain silo structures that were in close proximity to Hangar 12. Within the city, historical masonry structures, older reinforced concrete structures, and modern high-rise structures were impacted. Through a combination of in-person inspections and street-view surveys, we collected data on structural performance (including damage to load-bearing elements) and building façades. Performance levels were classified according to procedures applied following earthquakes (for structural performance) and newly proposed procedures (for façades). We describe spatial distributions of these damage types and dependencies on source distance and location-to-explosion direction. We demonstrate that physical damages correlated with damage proxy maps produced by the Jet Propulsion Laboratory and the Earth Observatory of Singapore based on Copernicus Sentinel-1 satellite synthetic aperture radar data, with a stronger correlation with structural damage than with façade damage. 

The 2019 Ridgecrest earthquake sequence produced a 4 July M 6.5 foreshock and a 5 July M 7.1 mainshock, along with 23 events with magnitudes greater than 4.5 in the 24 hr period following the mainshock. The epicenters of the two principal events were located in the Indian Wells Valley, northwest of Searles Valley near the towns of Ridgecrest, Trona, and Argus. We describe observed liquefaction manifestations including sand boils, fissures, and lateral spreading features, as well as proximate non‐ground failure zones that resulted from the sequence. Expanding upon results initially presented in a report of the Geotechnical Extreme Events Reconnaissance Association, we synthesize results of field mapping, aerial imagery, and inferences of ground deformations from Synthetic Aperture Radar‐based damage proxy maps (DPMs). We document incidents of liquefaction, settlement, and lateral spreading in the Naval Air Weapons Station China Lake US military base and compare locations of these observations to pre‐ and postevent mapping of liquefaction hazards. We describe liquefaction and ground‐failure features in Trona and Argus, which produced lateral deformations and impacts on several single‐story masonry and wood frame buildings. Detailed maps showing zones with and without ground failure are provided for these towns, along with mapped ground deformations along transects. Finally, we describe incidents of massive liquefaction with related ground failures and proximate areas of similar geologic origin without ground failure in the Searles Lakebed. Observations in this region are consistent with surface change predicted by the DPM. In the same region, geospatial liquefaction hazard maps are effective at identifying broad percentages of land with liquefaction‐related damage. We anticipate that data presented in this article will be useful for future liquefaction susceptibility, triggering, and consequence studies being undertaken as part of the Next Generation Liquefaction project.