<P> Beginning in February 1989, climatologist Iben Browning--who claimed to have predicted the 1980 eruption of Mount St. Helens and the 1989 Loma Prieta earthquake--predicted that there was a 50 percent probability of a magnitude 6.5 to 7.5 earthquake in the New Madrid area sometime between December 1 and December 5, 1990 . Browning appears to have based this prediction on particularly strong tidal forces being expected during that time frame and his opinion that a New Madrid earthquake was "overdue"; however, seismologists generally agree that there is no correlation between tides and earthquakes . The United States Geological Survey requested an evaluation of the prediction by an advisory board of earth scientists, who concluded that "the prediction does not have scientific validity ." Despite the lack of scientific support, Browning's prediction was widely reported in international media, causing public alarm . The period passed with no major earthquake activity in New Madrid or along the 120 - mile (190 km) fault line . </P> <P> The lack of apparent land movement along the New Madrid fault system has long puzzled scientists . In 2009, two studies based on eight years of GPS measurements indicated that the faults were moving at no more than 0.2 millimeters (0.0079 in) a year . This contrasts to the rate of slip on the San Andreas Fault, which averages up to 37 mm (1.5 in) a year across California . </P> <P> On March 13, 2009, a research group based out of Northwestern University and Purdue University, funded by the United States Geological Survey, reported in the journal Science and in other journals that the New Madrid system may be "shutting down" and that tectonic stress may now be accumulating elsewhere . Seth Stein, the leader of the research group, published these views in a book, Disaster Deferred, in 2008 . Although some of these ideas have gained some amount of acceptance among researchers, they have not been accepted by the National Earthquake Prediction Evaluation Council, which advises the USGS . </P> <P> In the November 5, 2009, issue of Nature, researchers from Northwestern University and the University of Missouri said that due to the lack of fault movement, the quakes along the faults may only be aftershocks of the 1811--1812 earthquakes . </P>

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