Scientists say a fault-line running across Alaska could cause tsunamis of the same magnitude as the Japanese disaster of March last year. Attention has turned to the Alaskan-Aleutian subduction zone, a region where one of the earth's tectonic plate, carrying the Pacific Ocean, drops beneath the North American plate.

A particular section of the fault near the Semidi Islands has not ruptured since at least 1788, and measurements on this area - which lies four to five kilometres under water - reveal the pressure is accumulating rapidly. If the Pacific Ocean plate slips, as happened in the geographically-similar Tohoku subduction zone off the coast of Japan, a tsunami could occur - and the deaths could happen as far away as Hawaii and California.
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© GoogleThe Semidi Islands lie close to the faultline, and an earthquake could send a tsunami towards Hawaii and California

According to Discovery.com, scientists are now investigating the underwater fault-line in the hope of estimating the likelihood of danger to the U.S. and to the Hawaiian islands.

The last time a slip between the Alaskan plates occurred led to the Good Friday Earthquake, on March 27, 1964, which was the powerful earthquake in U.S. history - a 9.2 magnitude earthquake which led to 145 deaths.

Tsunamis also occurred in this area in 1947 and 1957, while a magnitude 7.4 earthquake occurred in the area last June, but as its location did not lead to a tsunami, a brief tsunami warning was recalled shortly afterwards.

Many of these deaths happened hundreds of miles away from the epicentre of the earthquake - with 90 per cent of the deaths caused by tsunamis.

The Japanese quake, which measured 9.0 magnitude, led to a 10-metre-high tsunami and ended up killing an estimated 18,000 people.