Chile earthquake generates cross-Pacific tsunami

People in Hawaii were urgently told to protect lives and property from a tsunami crossing the Pacific as fast as a jetliner after a devastating earthquake in Chile.

Tsunami waves were likely to hit Asian, Australian and New Zealand shores within 24 hours of the earthquake, which struck early Saturday on Chile's coast.

Though notoriously hard to predict, the tsunami was not expected to be as devastating as the waves generated after a magnitude-9.5 earthquake hit Chile in 1960. Most countries, awaiting further data, did not order evacuations Saturday but instead advised people in low-lying areas to watch for further updates.

The Pacific Tsunami Warning Center in Hawaii advised that a tsunami was possible in the northern Pacific, including the U.S. West Coast and Alaska.

"Sea-level readings confirm that a tsunami has been generated which could cause widespread damage," the center said in a bulletin after the magnitude-8.8 quake. "Authorities should take appropriate action to respond to this threat."

The center noted that tsunami wave heights are difficult to predict because they can vary significantly along a coast due to the local topography.

Some Pacific nations in the warning area were heavily damaged by a tsunami last year. On Sept. 29, a tsunami spawned by a magnitude-8.3 earthquake killed 34 people in American Samoa, 183 in Samoa and nine in Tonga. Scientists later said that wave was 46 feet (14 meters) high.

Past South American earthquakes have had deadly effects across the Pacific.

A tsunami after the magnitude-9.5 quake that struck Chile in 1960, the largest earthquake ever recorded, killed about 140 people in Japan, 61 in Hawaii and 32 in the Philippines. That tsunami was about 3.3 to 13 feet (one to four meters) in height, Japan's Meteorological Agency said.

The tsunami from Saturday's quake was likely to be much smaller because the quake itself was not as strong.

Japanese public broadcaster NHK quoted earthquake experts as saying the tsunami would likely be tens of centimeters (inches) high and reach Japan in about 22 hours. A tsunami of 28 centimeters (11 inches) was recorded after a magnitude-8.4 earthquake near Chile in 2001.

The Meteorological Agency said it was still investigating the likelihood of a tsunami from the magnitude-8.8 quake and did not issue a formal coastal warning.

Australia, meanwhile, was put on a tsunami watch.

The Joint Australian Tsunami Warning Center issued a tsunami warning Saturday night for a "potential tsunami threat" to New South Wales state, Queensland state, Lord Howe Island and Norfolk Island. Any potential wave would not hit Australia until Sunday morning local time, it said.

The Philippine Institute of Vulcanology and Seismology issued a low-level alert saying people should await further notice of a possible tsunami. It did not recommend evacuations.

Seismologist Fumihiko Imamura, of Japan's Tohoku University, told NHK that residents near ocean shores should not underestimate the power of a tsunami even though they may be generated by quakes thousands of miles (kilometers) away.

"There is the possibility that it could reach Japan without losing its strength," he said.

(Copyright 2010 by The Associated Press. All Rights Reserved.)