THE CALIFORNIA EARTHQUAKE CLEARINGHOUSE – RIDGECREST EARTHQUAKE SEQUENCE 2019

Following the damaging 1971 San Fernando Earthquake, after-action reports recognized the collective efforts of scientific and engineering responders and the value and urgent need for organized crisis response and communication, especially for urban areas. In 1972, the California Post-Earthquake Information Clearinghouse was established. After a major and/or damaging earthquake in California, the California Geological Survey is mandated to establish a clearinghouse in coordination with its managing partners, United States Geological Survey, Earthquake Engineering Research Institute, California Office of Emergency Services, and California Seismic Safety Commission, to provide disaster response managers, affected agencies, and the scientific community with prompt information on ground failure, structural damage, and other consequences of a significant seismic event. The July 2019 Ridgecrest earthquake provided an opportunity to exercise the Clearinghouse, including 7 days onsite, coordinating response and access to restricted areas, with over 50 experts from federal, state, public, and private organizations. Expertise spanned many disciplines: geosciences, geotechnical engineering, structural engineering, nonstructural components, insurance, lifelines, transportation, risk analysis, and business continuity. The EERI “Learning From Earthquakes” program provided event virtual clearinghouse support to share field data, photos, preliminary reports, and links to imagery. A suite of GIS and other digital tools were available to rapidly collect and compile field data leading to the timely synthesis of data for situational awareness maps, images for media, areas of interest for lidar collection, and assisting field teams to efficiently map a broad rupture region. The 2019 Ridgecrest Earthquake Sequence provided an opportunity to test and refine methods for rapidly collecting and disseminating field observations after a large and complex surface rupturing earthquake.