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WITHDRAWN Developing a New Intensity Measure for USGS’s ShakeMap: Cumulative Absolute Velocity (CAV)

Description: 

WITHDRAWN The U.S. Geological Survey's (USGS) ShakeMap has been providing rapid, global estimates of earthquake shaking metrics for decades. The USGS has provided ground shaking metrics as maps of intensity measures (IM) such as peak ground velocity, peak ground acceleration, spectral acceleration (at three periods), and macroseismic intensity. These products have been effectively used by emergency managers, loss modelers, engineers concerned about post-event structural performance, and by risk analysts for insurance products. However, more advanced IMs offer important benefits for characterizing the ground shaking intensity by accounting for energy and duration of shaking, which have the potential to be useful for applications that include assessing the potential for failure involving landslides, liquefaction, and critical infrastructure. These metrics include cumulative absolute velocity (CAV), Arias intensity, significant duration, and permanent static displacement. Since the USGS produces ShakeMaps for events around the globe, we present a framework for implementing CAV in ShakeMap. Fortunately, there are numerous ground motion models (GMMs) models to estimate CAV that are applicable to several regions and tectonic environments. We start by developing the tools to calculate CAV from earthquake records in the software package gmprocess. We then develop a database of recorded CAV values from the conterminous United States, Alaska, and Hawaii along with predicted CAV values from GMMs that include quality control. We use OpenQuake to predict CAV values for a total of five existing and new contributed GMMs for CAV. One complicating factor is that some CAV GMMs are conditional models, which had not yet been implemented in OpenQuake. It is also imperative that we test and expand the suitability of the CAV models for all possible regions and tectonic environments with our new database which will be used to develop the necessary spatial correlation models for ShakeMap. We expect our work to improve assessment of liquefaction hazards, impacts to infrastructure, and to advance earthquake science and operations.

Session: Earthquake Shaking and the Geologic Record: Triggered Phenomena and Preserved Fragile Geologic Features [Poster]

Type: Poster

Date: 4/17/2025

Presentation Time: 08:00 AM (local time)

Presenting Author: Kyle

Student Presenter: No

Invited Presentation: 

Poster Number: 28

Authors