New looks lower guesses on 1811-12 quake strengths

MEMPHIS, Tenn. — Some earthquake scientists say they think previous estimates of the strength of the 1811-12 New Madrid earthquakes in the Midwest were too high.

The Seismological Society of America is meeting at Memphis. The Memphis Commercial Appeal says one of the papers to be presented argues that the quakes in northeast Arkansas and southeast Missouri during the winter of 1811-1812 weren't nearly as powerful as previous estimates of magnitude 7.7 or greater.

Susan E. Hough of the U.S. Geological Survey says new reviews by independent experts put the magnitude of the three main earthquakes at a maximum of about 7.0.

University of Memphis seismologist Chris Cramer said accurate estimates of the power of those quakes could help predict how buildings will hold up in any new major quake in the area.