Scientists Warn New Madrid Seismic Zone Is Overdue for a Major Quake
Geological Society of America report says a magnitude 7.6 event could cause tens of billions in damage as officials renew focus on preparedness
A major earthquake in the New Madrid Seismic Zone (NMSZ) — a broad fault system in the central United States — is overdue and could inflict catastrophic damage on communities and infrastructure across the Mississippi River Valley, scientists and recent studies warn.
The Geological Society of America’s 2025 assessment concluded that a magnitude 7.6 earthquake in the NMSZ could cause more than $43 billion in direct damage. Previous academic and government estimates have placed potential fatalities from a large event in the tens of thousands, with some studies suggesting death tolls could exceed 80,000 depending on magnitude, location and time of day. Federal and local officials have been planning for decades for the consequences of a major NMSZ earthquake and have produced multiple scenario-based estimates of damage from events stronger than magnitude 6.0.
The NMSZ stretches roughly 150 miles along the Mississippi River Valley and covers parts of northeastern Arkansas, southeastern Missouri, western Tennessee, western Kentucky and southern Illinois. It is among the most active earthquake regions east of the Rocky Mountains, producing hundreds of small earthquakes each year while lacking the public profile of Californian or Alaskan seismic zones.
The most recent historically documented major earthquakes in the area occurred in the winter of 1811–1812, when a sequence of strong temblors was felt across much of the central and eastern United States. Geological investigations since then — including paleoseismology studies that identify sand blows, liquefaction features and other ground disturbances — indicate the zone has produced major earthquakes in the past and retains the capacity to do so again.
Experts note several factors that amplify the hazard in the central U.S. compared with the West. Earthquake waves travel farther in older, colder continental crust east of the Rockies, which can spread shaking over wider areas. Much of the built environment in the Mississippi Valley was not designed for strong seismic shaking; critical infrastructure such as bridges, river levees, water and power systems, and pipelines could be vulnerable to widespread damage. The alluvial soils that line the river valley are prone to liquefaction, which can greatly increase local damage even in moderate shaking.
Estimating the probability and timing of a large NMSZ quake remains difficult. Intraplate faults like the New Madrid system do not follow the more regular recurrence patterns of plate-boundary faults, and long intervals between major events are common. Scientists use a combination of historical records, geological field evidence and modern instrument data to update hazard models, but uncertainty in recurrence intervals and maximum magnitudes persists.
State and federal agencies have used scenario modeling to plan responses and guide mitigation. Those efforts include evaluations of likely structural failures, disruptions to transportation and commerce along the Mississippi River, impacts on hospitals and emergency services, and secondary hazards such as dam or levee breaches. Emergency planners have emphasized coordination across state lines because the NMSZ spans multiple jurisdictions and a large earthquake would have regional consequences for supply chains and utilities.
Researchers and officials stress that continued monitoring, targeted retrofits of critical infrastructure and community preparedness can reduce the potential human and economic toll of a major event. Seismic monitoring networks have improved coverage and sensitivity in the region in recent decades, allowing scientists to track small earthquakes and better characterize fault behavior.
While the exact timing of the next large earthquake in the New Madrid Seismic Zone cannot be predicted, the combination of geological evidence for past large events, ongoing low-level seismicity, vulnerable infrastructure and the potential for long-distance shaking underpins scientific and emergency-management concern. Continued research, investment in resilience and public preparedness remain central to reducing risk in the nation’s interior.
This story reflects recent scientific assessments and governmental planning efforts concerning seismic hazard in the central United States and does not predict the timing of any specific event.