Scientists have found that 75 percent of the US – home to hundreds of millions of Americans – is at risk of damaging earthquakes.
The US Geological Survey (USGS) has released the latest National Seismic Hazard Model that includes 350 newly discovered fault lines since the previous model in 2018 – bringing the total to approximately 1,000 fault lines.
The updates increased the risk of catastrophic earthquakes in the central and northeastern “Atlantic Coast Corridor,” where Washington DC, Philadelphia, New York and Boston are located.
Seismically active regions of California, Alaska and Hawaii also experienced increased risk; certain parts of the Golden State now have a 95 percent chance of damaging earthquakes in the next century.
USGS also projected that based on the updated model, there will be average economic losses of $14.7 billion per year due to ground shaking damage to buildings.
The new model has been turned into a map, showing the chances of damaging earthquakes hitting different parts of the US. California’s coast has a 95 percent chance, while New York City has a maximum 25 percent chance in the next 100 years
Mark Petersen, USGS geophysicist and lead author of the study, said in a statement: ‘Earthquakes are difficult to predict, but we have made great progress with this new model.
‘The update includes more faults, better characterized land surfaces and computational improvements in modeling that provide the most detailed picture ever of the earthquake risks we face.’
The research was conducted by more than fifty reviewers and hundreds of hazard scientists and end users, who attended public workshops and provided technical input.
“This was a massive, multi-year collaboration between federal, state and local governments and the private sector,” Petersen said.
“The new seismic hazard model is a milestone for improving public safety.”
The US Geological Survey (USGS) has released the latest National Seismic Hazard Model with 350 newly discovered fault lines since the previous model in 2018 (photo)
Pictured is the 2023 model, which shows more areas in the US at risk
A massive magnitude 6.4 earthquake struck northern California in 2022, leaving tens of thousands of people without power. The updated model shows the state has a 95 percent chance of causing earthquakes in the next 100 years
To create the updated hazard assessment, the team used declustering algorithms that can analyze specific details of earthquakes, such as the time and distance window of the mainshock.
Gridded seismicity models were part of the study, which takes into account ground shaking due to earthquakes on known faults, as well as earthquakes on unmodelled faults.
The team also integrated fault-based structural and deformation models, multi-fault earthquake rupture prediction models, semi-empirical and simulation-based ground motion models, and site amplification models.
The model showed that 25 states have a moderate to higher chance of earthquakes in the next 100 years.
The model showed that 25 states have a moderate to higher chance of earthquakes in the next 100 years
The locations include California, Washington, Oregon, Utah, Wyoming, Nevada, Tennessee, Arkansans, Indiana, Missouri, South Carolina, Alaska and Hawaii.
‘Colorado, Wyoming and Montana increased significantly due to changes in methodology, the team shared in the study published in the journal Earthquake spectra.
New York, Illinois and Texas also appeared to be in the danger zone.
‘Our forensic analysis comparing the current and previous National Seismic Hazard Models shows a substantial (60 percent) increase in hazard ratios in lower seismic areas such as New York City as a result of the treatment in prioritizing the input earthquake catalogs’ , says the study.
The team also found that 37 states have experienced earthquakes greater than magnitude 5 in the past 200 years, indicating a long history of seismic activity in this country.