JAPAN EARTHQUAKE

TOKYO -- A magnitude 8.9 earthquake slammed Japan's northeastern coast Friday, unleashing a 13-foot tsunami that swept boats, cars, buildings and tons of debris miles inland and prompting a "nuclear emergency."

At least 40 people were killed and there were reports of several injuries in Tokyo, hundreds of miles away, where buildings shook violently through the main quake and the series of massive aftershocks that followed.Recent analysis of historical data shows that four of the top ten most deadly earthquakes and tsunamis since 1701 occurred in the last decade, including the 2004 Indian Ocean (Sumatra) and 2010 Haiti events. The magnitude 8.8 2010 Chile earthquake was the fifth largest earthquake ever recorded. These events generate questions about the frequency and severity of geologic natural hazards worldwide. The National Geophysical Data Center and co-located World Data Center for Geophysics and Marine Geology maintain a global historical event database of tsunamis, significant earthquakes, and significant volcanic eruptions (http://www.ngdc.noaa.gov/hazards/). Analysis of the database revealed that while the total number of magnitude 7.5 earthquakes per decade since 1901 has remained consistent, the last decade has experienced some of the most devastating geologic events in history. Until 2010, the most deadly event in the Caribbean was the 1902 eruption of Pelee that caused 28 000 deaths.