BBC NEWS Americas Africa Europe Middle East South Asia Asia Pacific
BBCi NEWS   SPORT   WEATHER   WORLD SERVICE   A-Z INDEX     

BBC News World Edition
 You are in: Science/Nature  
News Front Page
Africa
Americas
Asia-Pacific
Europe
Middle East
South Asia
UK
Business
Entertainment
Science/Nature
Technology
Health
-------------
Talking Point
-------------
Country Profiles
In Depth
-------------
Programmes
-------------
BBC Sport
BBC Weather
SERVICES
-------------
EDITIONS
Thursday, 15 August, 2002, 18:18 GMT 19:18 UK
Japan faces tidal wave threat
Map of newly-discovered fault, Science
Seismic reflection imaging revealed the fault
Image © Science

Scientists in Japan have discovered a fault in the seabed off the country's coast with the potential to unleash a giant "tsunami" tidal wave.


Any tsunami could hit the mainland with only a few minutes' warning

Bill McGuire
Benfield Greig Hazard Research Centre
The newly-detected fault lies off the south-eastern coast of Japan and may have been responsible for the magnitude 8.1 earthquake which struck the country in 1944, they say.

Jin-Oh Park and his colleagues at Jamstec, the Japan Marine Science and Technology Center, say that an earthquake along the fault would threaten cities along the Japanese coast.

The fault is close enough to the Japanese coast for there to be only minutes between a substantial earthquake along it and the tsunami reaching land.

Uncharted sea bed

The fault, which lies close to where the Philippine Sea plate is sinking beneath the Eurasian plate, is only dozens of kilometres away from land.

"Any tsunami would hit the mainland with only a few minutes' warning," explained Bill McGuire, director of the UK's Benfield Greig Hazard Research Centre.

BBC map/Science graphic
The fault is off Japan's south-eastern coast
"Most people in Japan live along the coast and evacuating them in only a few minutes would be impossible," he said.

"It's an additional tsunami risk in a country that has many of them," he added.

The newly-discovered fault was uncovered by seismic reflection imaging.

Submarine faults are difficult to find and much of the ocean floor is still poorly understood.

Faults may never protrude above the ocean floor or may be covered in sediment.

History of disaster

Jin-Oh Park and his colleagues believe that the fault they have found may have been responsible not just for a magnitude 8.1 quake in 1944, but a nearby magnitude 8.3 quake two years later.

Very large earthquakes tend to occur every 100 to 200 years along faults of the kind now discovered, they explain.

Details of the fault's discovery appear in the journal Science.

See also:

19 Jul 02 | Science/Nature
04 Jun 02 | Science/Nature
29 Aug 01 | Science/Nature
Internet links:


The BBC is not responsible for the content of external internet sites

Links to more Science/Nature stories are at the foot of the page.


E-mail this story to a friend

Links to more Science/Nature stories

© BBC ^^ Back to top

News Front Page | Africa | Americas | Asia-Pacific | Europe | Middle East |
South Asia | UK | Business | Entertainment | Science/Nature |
Technology | Health | Talking Point | Country Profiles | In Depth |
Programmes