LOS ANGELES (AP) - New research suggests the New Madrid (MAD'-rihd) fault zone in the nation's midsection is active and could spawn future large earthquakes.
Researchers have long debated just how hazardous New Madrid is. The zone stretches 150 miles, crossing parts of Arkansas, Illinois, Indiana, Kentucky, Mississippi, Missouri and Tennessee. It was the site of three powerful jolts in 1811 and 1812.
Previous studies have suggested that it may be shutting down, based on GPS readings showing little strain accumulation at the surface. Other research has blamed ongoing quake activity on aftershocks from the 1800s , which would relax the fault.
The new work by U.S. Geological Survey scientists in California suggests otherwise. Analyzing past quakes and using models, they conclude the zone is active.
Results were published online Thursday in Science.