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TSUNAMI

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					      TSUNAMI



    R.DIVYABHARATHI
I YEAR CIVIL ENGINEERING
TSUNAMI

      •   INTRODUCTION
      •   CAUSES
      •   EFFECTS
      •   CONCLUSION
              INTRODUCTION
• A tsunami is a series of ocean waves that sends
    surges of water, sometimes reaching heights of
    over 100 feet (30.5 meters), onto land. These
    walls of water can cause widespread destruction
    when they crash ashore.
•   These awe-inspiring waves are typically caused
    by large, undersea earthquakes at tectonic plate
    boundaries. When the ocean floor at a plate
    boundary rises or falls suddenly it displaces the
    water above it and launches the rolling waves
    that will become a tsunami.
                          CAUSES
• Shallow undersea earthquakes are responsible for most tsunamis
  though at time landslides triggered by smaller seismic events can
  also generated potentially lethal waves. Strong earthquakes cause a
  displacement of the crust. When they occur underwater, this crustal
  movement disturbs a large volume of water like a giant paddle and
  ripples spread out in all directions at speeds of 600-800 kilometres
  per hour, comparable to commercial aircraft. In the open ocean,
  they go unnoticed but once they reach shallower waters they slow
  down and begin to crest. The waves thus given rise to are known as
  "Tsunamis". They are scientifically described as a series of very long
  wavelength ocean waves caused by the sudden displacement of
  water by earthquakes, landslides, or submarine slumps and are
  mostly caused by earthquakes of magnitude 7.5 or greater. The
  run-up of a tsunami is the maximum height above normal sea level
  up to which the water level rose during a tsunami
EFFECTS
    • As you many know a tsunami is
       caused by a strong earthquake on the
       ocean bed. The vibrations travel
       through the water traveling sometimes
       thousands of kilometers. If you were
       on the water or deep sea diving in
       SCUBA gear you would not notice
       much probably just rough waves or a
       momentarily strong downward pull if
       you were underwater. However, a
       tsunami gains its true destructive
       power as it approaches land. The
       water level becomes shallower causing
       the waves caused by the earthquake
       to compress and combine. This is what
       creates the massive and destructive
       waves that cause so much destruction
CONCLUSION
     • WE CAN FIND IT
         THROUGH
         SATTELIGHTS
     •   WE FORM OUR
         HOUSES AWAY FROM
         SEAS
THANK YOU

				
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