RWG24 (Scenario Catalog)

CalOES Hypothetical Doublet Scenarios in California

Contact

Email

Robert W Graves <rwgraves@usgs.gov>

Description

The occurrence and impact of the February 2023 earthquake doublet in Türkiye, where an Mw 7.8 event was followed roughly 9 hours later by an Mw 7.5 event on an adjacent fault, begs the question: What would be the impact of such a sequence in California? As part of the effort to address this question, this Data Release consists of simulated ground motions for a hypothetical doublet scenario on the Newport-Inglewood and Palos Verdes faults in the Los Angeles region, and the Hayward and Calaveras faults in the San Francisco Bay region. The fault locations and orientations are based on the 2023 USGS National Seismic Hazard Model.

Purpose

These data were simulated in order to facilitate assessment of potential impacts of an earthquake "doublet" occurring in the San Francisco Bay region of California. In an earthquake doublet, an initial large magnitude (M7+) earthquake is followed several hours later by another large magnitude event occurring in close proximity to the first event. The impact assessment must consider the cascade of effects related to both events, e.g., the first event partially damaging a structure leaving it in a compromised state, which is then again subjected to strong shaking in the second event. The simulated broadband three-component time series can be used in the same manner as recorded earthquake ground motion data in any application requiring the use of such data. Furthermore, the scenario ShakeMaps derived from the simulations can be utilized in any application requiring USGS ShakeMap data as input (e.g., regional loss estimation).

References