The new research, published in the journal Lithosphere, examined earthquake records in China. Earthquakes have been recorded and described in China for some 2,000 years, but have never occurred twice in the same place.
"In North China, where large earthquakes occur relatively frequently, not a single one repeated on the same fault segment in the past 2,000 years," said Mian Liu, a professor of geological sciences at University of Missouri and one of the authors of the new study. "So we need to look at the 'big picture' of interacting faults, rather than focusing only on the faults where large earthquakes occurred in the recent past."
Different faults form a web of interacting stresses. A large earthquake on one fault can increase stress on a different fault. Important faults can remain dormant for years then jolt awake in a brief period of violent activity.
Seth Stein, a co-author of the paper and professor of earth and planetary sciences at Northwestern University, said that Global Positioning System measurements taken in the past two decades have found no significant strain in the New Madrid area.
The following video offers a good introduction to the New Madrid fault:
There's a whole lot of shaking going on away form the New Madrid area, on the West Coast of the US of late, with an increase in these moderate quakes.
"The magnitude 5.2 temblor was reported at 2:01 p.m. Tuesday. According to the U.S. Geological Survey, it was felt in parts of Northern California as well as in Oregon.
Earlier in the day, a magnitude 4.7 quake was reported at 7:44 a.m. about 180 miles west of Coos Bay."
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