Advanced Seismic Model Pinpoints Earthquake Vulnerability

An updated USGS National Seismic Hazard Model (NSHM) using the latest data collection technologies indicates that nearly 75 percent of the U.S. could experience a damaging earthquake, according to the U.S. Geological Survey study.

The study included more than 50 scientists and engineers, using the NSHM to create a color-coded map to pinpoint the most likely locations to suffer from a damaging earthquake. The model used insights from seismic studies, historical geological data and modern tools to create ground-motion maps that indicated that hundreds of millions of people are at risk.

The ground-motion maps and 3D simulations showed changes that suggest the possibility of more damaging earthquakes than previously thought along the central and northeastern Atlantic Coastal corridor, including in Washington, D.C.; Philadelphia; New York; and Boston. It also showed the possibility of even greater shaking in California and Alaska and Hawaii.

“This was a massive, multiyear collaborative effort between federal, state and local governments and the private sector,” Mark Petersen, USGS geophysicist and lead author of the study, said in a USGS report. “The new seismic hazard model represents a touchstone achievement for enhancing public safety.”

Some key points from the study were that 37 U.S. states have experienced earthquakes of more than magnitude 5 in the last 200 years; this was the first National Seismic Hazard Model to include all 50 states simultaneously. The report said the model will help inform architects, policymakers and engineers on the future of building design.

“Earthquakes are difficult to forecast but we’ve made great strides with this new model,” Petersen said. “The update includes more faults, better characterized land surfaces, and computational advancements in modeling that provide the most detailed view ever of the earthquake risks we face.”