Latest Seismic moment Stories

(AP) -- Sunday's earthquake in Sumatra had a preliminary magnitude of 9.0, classifying it as a great quake and making it the strongest in 40 years. Earthquakes near the very top of the magnitude scale are difficult for scientists to measure. For one thing, they occur rarely - once a year or less - so researchers don't have many chances to analyze them. And, the tools that scientists use to measure movements in the planet's crust are becoming more sophisticated. So the way in which they assign...