Page 111 - Active Science 5 Ebook and Activity

• Damage to property and loss of life

• Sunlight is blocked by the thick volcanic dust.

Advantages of Volcanic Eruptions Factual Study
• After a volcanic eruption, the huge The Pacific Ring of Fire is an area of

amount of ash released covers the soil frequent earthquakes and volcanic
making it very fertile and useful for eruptions encircling the basin of the Pacific
Ocean. There are 452 volcanoes in the Ring
farming.
of Fire and it is home to over 50% of the
• Volcanoes provide resources for energy world’s active and dormant volcanoes. 90 %

such as geothermal energy. of the world’s earthquakes and 81% of the
world’s largest earthquakes occur along the
Ring of Fire.
T idal Waves and Tsunami

Tidal waves cause changes in the level of water bodies. These changes occur due to the
gravitational force of the sun and the moon. Sometimes, these waves are high or low.
When the sun, moon and earth are in a straight line, tides reach to the maximum height.

When huge waves form from oceans, due to volcanic eruptions or earthquakes under

water, they are called tsunami. As the tsunami gets closer to land and ocean, its depth
decreases, the speed of the tsunami waves slows down and the height of the tsunami
waves increases along with its potential for destruction. These huge waves lead to loss of
life and property. So, it is advisable to stay at a high altitude following a tsunami alert.

The tsunami which took place in India on

December 26, 2004, caused a major loss of
life and property in coastal regions of Tamil
Nadu and Kerala. The worst hit areas were
the Andaman and Nicobar Islands.

Tidal waves

Let’s Recapitulate

1. All natural disasters come without _____________.
2. There are three types of volcanoes – _____________, ____________ and _____________.

3. The deep point inside the earth from where an earthquake starts is called ____________.
4. The intensity of earthquake is detected by _____________.
5. Volcanoes provide resources for energy called _____________.

F loods

A flood is an overflow of water when the water bodies like rivers, lakes and ponds are
overfilled with rain water. Next of some natural factors causing floods are:

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