Ridgecrest, CA earthquake sequence, July 4 and 5, 2019

The Ridgecrest Earthquake sequence included a M6.4 event on July 4 2019 followed by a M7.1 July 5 2019. These events occurred in the Eastern California Shear Zone, near Indian Wells Valley, south of China Lake and west of Searles Valley. The Geotechnical Extreme Events Reconnaissance (GEER) Association has partnered with several organizations to collect perishable data and document the important impacts of these events, including the United States Geological Survey, the California Geological Survey, the US Navy, the Southern California Earthquake Center, the National Aeronautics and Space Agency (NASA) Jet Propulsion Laboratory (JPL), and local utilities. Critical geotechnical features of this event are extensive surface ruptures, roads, water pipes, and gas pipes crossing the faults, liquefaction and lateral spreading, and liquefaction effects on structures. These effects are documented using field (ground) mapping, and Structure from Motion (SfM) using images collected by UAV's to develop high-resolution digital elevation models.