Page 147 - SST Class 07

Tsunami plates. The sliding of the tectonic plates resulted
The term ‘Tsunami’ comes from the words ‘tsu’
meaning harbour and ‘nami’ meaning waves. It
means huge tidal waves. A tsunami can be
caused due to underwater earthquakes, volcanic
eruptions and underwater explosions.
On December 26, 2004, a deadly tsunami
occurred in the Indian Ocean due to earthquake
called the Sumatra-Andaman earthquake. Its
epicenter was off the west coast of Sumatra in
Indonesia.
Tsunami
The earthquake which measured 9.0 on the
Richter Scale caused a series of tsunami that
caused devastation and destruction on the coasts
of countries bordering the India Ocean.
The tsunami affected the coastal areas across
South and South-East Asia. India, Indonesia, Sri
Lanka and Thailand were the countries where
destruction was maximum. Coastal areas of
Malaysia, Myanmar, Bangladesh, Maldives and
East African countries of Somalia, Kenya,
Tanzania and Madagaskar also suffered serious
damage. In India, the coastal areas of Andhra
Pradesh, Tamil Nadu, Kerala, Pondicherry and
Andaman and Nicobar Islands were the worst
affected. The Indira Points, which was the
Southernmost point of India was completely
submerged.
The earthquake that caused the tsunami origi-
nated due to the movement of the lithosphere
Social Science-7 147
in the earthquake which caused huge waves
some of which were as high as 30 meters.
The tsunami wreaked havoc on the communities
living in the coastal areas. More than 1.8 lakhs
lives were lost, about 42,000 people were
reported missing. The damage to property was
unaccountable. Houses were flattened, trees &
electric poles uprooted, automobiles submerged,
agricultural land flooded with saline water.
Several people lost their livelihood. Devastation
was beyond imagination.
Relief poured in from all quarters – local, state,
nation and international. Providing food, water,
first aid, medical aid, clothes and shelter was an
uphill task. The government was able to mobilise
resources and respond almost immediately.
Though the rehabilitation work is almost com-
plete, yet healing the emotional scars and provid-
ing emotional support was not an easy task. Life
for many can never be the same.
Tides
Periodic rise and fall of ocean water at regular
intervals, twice a day, is called a tide. Tides are
experienced in oceans and seas. When the level
of seawater rises, it is high tide and when the
level falls, it is low tide. Gravitational attraction of
the moon and sun causes these tides. They occur
twice a day. As the moon is closer to the earth, it
exerts larger gravitational pull causing high tides.
Tides