A powerful earthquake in the South Pacific hurled a massive tsunami at the shores of Samoa and American Samoa yesterday, flattening villages and sweeping cars and people out to sea, leaving at least 99 dead and dozens missing, the Associated Press reported.
The earthquake, which the Japanese Meteorological Agency measured as a magnitude 8.3 on the Richter scale, struck at 6:48 a.m. local time at a reported depth of 32 kilometers [20 miles] and a distance of 190 kilometers [120 miles] from the Samoan islands, Nature.com’s The Great Beyond blog posted today. “But most of the damage came with the tsunami waves, measuring up to 6 meters [20 feet] in American Samoa, that hit shore shortly afterwards.”
The Nature blog went on to say that residents in Samoa complained of having little or no warning, “some saying they only had three minutes.”
“Had it happened in darkness, there could have been more disaster in terms of the number of those who died or are missing.”
“Had it happened in darkness, there could have been more disaster in terms of the number of those who died or are missing,” the BBC reported the prime minister of Samoa, Tuila’epe Sailele Malielegaoi, said.
Other news organizations quoted the prime minister as saying it all happened “like lightning.”
Some media coverage focused on whether the lessons of the 2004 tsunami that killed hundreds of thousands of people in the Indian Ocean had been heeded. Others wondered if the Pacific tsunami-warning system, that was supposed to have been extended to the Indian Ocean after the 2004 tsunami, had been effective.
The Pacific Tsunami Warning Center in Hawaii sent out a “tsunami watch” warning three minutes after the earthquake was detected to islands in the vicinity, including Samoa, American Samoa, the Cook Islands and Fiji, predicting that an earthquake of this size was likely to result in a tsunami, TimesOnline reported.
“Computer modeling allowed the center to predict arrival times and the likely height of incoming waves. It warned that American Samoa, which is around 200 kilometers [125 miles] from the epicenter, was likely to be hit by 3-meter [10-feet] waves within ten minutes and Samoa within 20 minutes of the quake,” TimesOnline said.
The earthquake is the warning.
Jonathan Bathgate, a seismologist from government agency Geoscience Australia. said that in a case like yesterday’s tsunami that struck Samoa, the earthquake was the warning, according to Time.com. “In an island nation, he said, ‘Once the earth shakes residents should take that as the warning and immediately find higher ground. Residents had roughly an hour to do so, as waves started to hit Samoa’s coast at 8 a.m.,” Time reported.
The U.S. Geological Survey measured a magnitude of 8.0 for the earthquake, posting this illustration on its Web site:
The purple lines show major tectonic boundaries of subduction zones. A subduction zone is the place where two tectonic plates come together, one riding over the other, according to the USGS.
You can read more about the forces that cause these seismic events on the National Geographic Web site Earthquakes.
National Geographic News coverage: