New map shows where devastating earthquakes are most likely to occur in the United States

Nearly 75 percent of the United States could experience devastating earthquakes, according to a recent U.S. Geological Survey-led team of more than 50 scientists and engineers.

This is one of the key findings of the latest USGS National Seismic Hazard Model (NSHM). The model was used to create a color-coded map that shows where devastating earthquakes are most likely to occur, based on information from seismic surveys, historical geological data and the latest earthquake technology. data gathering.

The research is published in the journal Earthquake spectra.

The NSHM update requested by Congress was created as a critical tool to help engineers and others mitigate how earthquakes affect the most vulnerable communities by showing the likely locations of earthquakes and the magnitude tremors they could produce. New tools and technologies have identified nearly 500 additional faults that could produce a devastating earthquake, illustrating the evolving landscape of earthquake research.

“This is a massive, multi-year, collaborative effort between federal, state and local governments and the private sector,” said Mark Petersen, a USGS geophysicist and lead author of the study. “The new seismic risk model represents a key achievement to improve public safety.”

The latest iteration, the first comprehensive assessment of 50 states, was updated from previous versions released in 2018 (bordering United States), 2007 (Alaska), and 1998 (Hawaii).

Notable changes in the new model show the possibility of more devastating earthquakes along the central and northeast Atlantic coastal corridor, including in the cities of Washington DC, Philadelphia, New York and Boston. Additionally, there is a risk of greater shaking in seismically active regions of California and Alaska. The new model also characterizes Hawai’i as having greater potential for shaking due to observations of recent volcanic eruptions and seismic unrest on the islands.

“Earthquakes are difficult to predict, but we have made great progress with this new model,” Petersen said. “The update includes more faults, better characterized land surfaces and computational advances in modeling that provide the most detailed view ever of the seismic risks we face.”

Key findings from the updated seismic risk model include:

• Risk to people: Nearly 75% of the United States could face potentially devastating earthquakes and intense ground shaking, putting hundreds of millions of people at risk.
• Widespread risk: 37 U.S. states have experienced earthquakes greater than magnitude 5 in the past 200 years, highlighting a long history of seismic activity across this country.
• Structural Implications: The updated model will inform the future of building and structural design, providing critical insights to architects, engineers, and policymakers about how structures are planned and constructed in the United States.
• Unified Approach: This is the first national seismic hazard model to encompass all 50 states simultaneously, reflecting a massive collaborative effort with federal, state, and local partners.
• This is not a prediction: no one can predict earthquakes. However, by studying past faults and earthquakes, scientists can better assess the likelihood of future earthquakes and the intensity of their shaking.