The Most Earthquake-Prone States in America

The most significant seismic activity in Colorado is associated with tectonic activity along the Rocky Mountains. The western part of the state, particularly the region near the Colorado-New Mexico border, is where most of the seismic events occur. The state has experienced both small and moderate earthquakes in the past.

Washington state lies in the Cascadia Subduction Zone, where the Juan de Fuca Plate is being subducted beneath the North American Plate. This region is capable of producing powerful seismic events, including megathrust earthquakes, which can have significant impacts.

Arizona is generally considered to have a low level of seismic activity, though it is hardly immune to earthquakes. The most significant activity occurs in the northern part of the state, near the Arizona-Utah border, and is associated with the tectonic activity of the Colorado Plateau and the transition zone to the Basin and Range Province.

Arkansas is situated in the New Madrid Seismic Zone, a fault system that extends across several states, including Arkansas, Missouri, Tennessee, and Kentucky. The most notable earthquake in Arkansas history occurred on Dec. 16, 1811, when a massive seismic event known as the New Madrid Earthquake struck the area with an estimated magnitude between 7.5 and 7.9 – so strong that it altered the course of the Mississippi River.

Utah sits on the boundary between the North American Plate and the Pacific Plate. It experiences frequent small to moderate earthquakes, particularly in the western part of the state near the Wasatch Fault Zone.

Texas has seen an increase in earthquake activity in recent years, mainly attributed to oil and gas operations, including fracking. The most seismically active areas include the western and central parts of the state, including the Dallas-Fort Worth area and the Permian Basin.

Montana is situated in an active tectonic region, with seismic activity associated with the Intermountain Seismic Belt. Earthquakes in Montana are generally less frequent and less intense compared to some other states.

Idaho is part of the Intermountain Seismic Belt and experiences moderate seismic activity. The state has several active fault systems, including the Lost River Fault and the Teton Fault.

Kansas is within the Humboldt fault zone, which extends from southeastern Kansas into northeastern Oklahoma and is associated with a series of faults that formed during the Pennsylvanian and Permian periods, approximately 300 million to 250 million years ago. The Humboldt fault zone is believed to be the result of crustal stresses associated with the uplift of the Ozark Plateau. It is considered relatively inactive today.

While more commonly associated with volcanic activity, Hawaii is also susceptible to earthquakes. The movement of magma and the presence of active volcanoes can trigger seismic events, especially on the Big Island.

Wyoming is located within the Intermountain Seismic Belt and experiences occasional seismic activity. The Teton Fault, located in the northwestern part of the state, is a significant seismic feature.

Nevada has numerous active fault lines, including the Walker Lane, which is capable of producing moderate to large earthquakes. The city of Las Vegas and surrounding areas are located in close proximity to fault lines, increasing their risk from seismic activity.

California is known for its high seismic activity and was the most earthquake-prone state in the continental U.S. until it was overtaken by Oklahoma, where many quakes are likely now caused by oil and gas activity, including fracking. The San Andreas Fault and other active fault lines run through the Sunshine State, making it susceptible to particularly large and destructive quakes.

Although not traditionally considered a highly seismic region, Oklahoma has experienced a surprising increase in earthquake activity in recent years – astonishingly, putting it ahead of California, which has always been one of the two most earthquake-prone states. This rise in seismicity has been attributed to oil and gas production processes, including fracking, which is the injection practice associated with oil and gas production.

Alaska experiences frequent earthquakes due to its location along the tectonic boundary between the Pacific Plate and the North American Plate. The state has a history of significant seismic events, including the 1964 Great Alaska Earthquake, the most powerful earthquake recorded in U.S. history.