System that will warn of impending tsunami developed

Washington: Seismologists have developed a system that warns of an impending tsunami only minutes after the initial earthquake, thus helping minimise the death toll by giving locals valuable time to move to safer ground.

Researchers hope the system, known as RTerg, will prevent the huge death toll in calamities like the 2004 Indian Ocean earthquake and tsunami, which killed over 230,000 people in fourteen countries, including India, Indonesia and Thailand.

"We developed a system that, in real time, successfully identified the Sumatran earthquake (in 2010) as a rare and destructive tsunami earthquake," study leader Andrew Neman said, reports the journal Geophysical Research Letters.

"Using this system, we could in the future warn local populations, thus minimising the death toll from tsunamis," added Newman, assistant professor at the Georgia Institute of Technology (GIT).

Typically, a large subduction zone earthquake (collision of two oceanic plates) ruptures at a rate near three km per second, anywhere from 20 to 50 km below the Earth's surface, according to a GIT statement.

When these earthquakes occur in the ocean, the resulting waves may measure only about 20 cm high for a 7.8 Richter quake.

Tsunami earthquakes, however, are a rare class of earthquakes that rupture more slowly, at 1-1.5 km per second and propagate up to the sea floor.

This makes the vertical uplift much larger, resulting in wave heights of up to 10-20 metres.

Such was the case with Sumatran earthquake, with reported wave heights of up to 17 metres and causing a death toll of approximately 430 people.