Earthquake in Japan; Hawaii, Alaska, US West Coast on Tsunami Alert

A 8.9 earthquake hit Japan Friday. The quake set off a 10-meter tsunami that that left 300 dead and caused an oil refinery fire and nuclear reactor issues. 100 people were swept to sea and a passenger train is missing. The US northwest, Alaska and Hawaii are under tsunami alert.

A tsunami alert has been issued to the entire Pacific basin. Hawaii is evacuating residents. Three major airports in the island chain have closed. Mexico and the Pacific coast of South America have been put on alert.

NOAA has issued tsunami warnings for the Pacific coastal U.S. from Point Concepcion in California, north through Oregon and Washington. The Pacific basin tsunami alert extends to British Columbia and Alaska from the Oregon-Washington border to Amichika Pass 125 miles west of Adak and Attu in the Aleutian chain.

Tsunamis travel quickly. They pick up debris as they go: cars, homes, buildings, even boats. Large ships have capsized and washed up on nearby beaches. According to Kyodo News agency, a ship with 100 people was swept away and one train remains unaccounted for. There are dozens of fires. An oil refinery blazed with nearby storage tanks perilously close. Nearly four and a half million residents are without power.

Japan's Sanriku area has been plagued with quakes. On Wednesday, a 7.2 earthquake hit the area. Japan is located on the "ring of fire", a geographical region known for unstable crust structures and ensuing volcanic activity. Indeed all of Japan is earthquake-prone. Ten percent of the earth's active volcanoes are located in Japan.

Movement of magma, below the earth's surface and through vent holes (volcanoes), as well as shifting plates beneath the surface (plate tectonics) are responsible for earthquakes. Like the ripples created when a stone is dropped in a pool of water, earthquakes create seismic waves. If these waves reach coastal areas, they are called "tsunamis" (harbor waves).

Friday's earthquake is the fifth largest earthquake in a century. It is the largest in Japan's history. The 1923 Kanto earthquake in Japan killed 140,000 and measured 7.9. In 1995, the Great Hanshin earthquake, measuring 7.2 hit the city of Kobe in Japan. This tsunami calls to mind the 2004 tsunami that ravaged many areas in Asia.

Follow Tsunami updates on NOAA's National Weather Service page.

"Marilisa Kinney Sachteleben writes from 25 years teaching K-8, special needs, adult education and homeschool. A mom of four, she cares about child welfare, family issues, health and safety. Marilisa writes for the Yahoo! Contributor Network about parenting issues."