TSUNAMI ON THE COAST

HOW PEOPLE STAYING ON THE COAST EXPERIENCING TSUNAMI

TSUNAMI TRAVEL TIME (TTT)

TSUNAMI TRAVEL IN THE OPEN OCEAN

In the open ocean, tsunami waves can travel as fast as a jet plane (640-960 km per hour). Tsunami waves can travel thousands of kilometres from their point of origin, affecting large areas of ocean. This map shows how rapidly (in hours) waves from the 2011 Japanese tsunami spread across the Pacific Ocean.

TSUNAMI RISK ZONES

Subduction zones are often the source of earthquakes that create tsunami. The waves can travel thousands of kilometres across the ocean.

TSUNAMI SOURCES

Tsunami causes: Most tsunami waves are started by earthquakes, usually on the ocean floor. Other causes include landslides, volcanic eruptions, weather events and meteors hitting Earth. Scientists do not know the cause of about 10 per cent of all tsunami events. Most tsunami events occur in the Pacific and Indian oceans.

RING OF FIRE

Around the Pacific Ocean is a region called the Ring of Fire. The edges of the tectonic plates interact to form highly active seismic belts. The ring contains about 90 per cent of the world's volcanoes, and most of the world's tsunami events originate in the area.

TECTONIC MOVEMENT

Tectonic Plates of the Earth

           

Plate boundaries are approximate.  Subduction plate boundaries are arbitrarily mapped.  Subduction of plates occurs in a wide zone of plate contact, instead of a definite boundary.   This zone is defined by a zone of frequent earthquakes.

Most large earthquakes are generated by subduction, including megathrust earthquakes that exceed the magnitude of 8.0.  The Sumatra Section of the subduction zone has been very active since the giant tsunami-generating megathrust earthquake of December 26, 2004, which reached 9.3 on the Richter Scale. (www.johomaps.com)

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Die Erdkruste, die äußere feste Hülle der Erde, besteht aus sieben großen und einer Vielzahl mittlerer und kleiner (Bruch-) Stücke, den Platten. Die Platten unter den Ozeanen sind ozeanische Platten (z.B. die Pazifische Platte), solche, die Kontinente tragen, sind kontinentale Platten (z.B. die Afrikanische Platte). Die Platten werden durch wärmebedingte Bewegungen tieferer Teile der Erde (Erdmantel) verschoben. Sie driften z. T. auseinander, gegeneinander und aneinander vorbei. Diese Bewegungen laufen etwa so schnell (oder langsam) ab, wie Fingernägel wachsen.