Presented by:

Md. Inzamul Haque Sazal

Dept. of Geography & Environment

Shahjalal University of Science & Technology, Sylhet-3114

Bangladesh.

Contents:

Introduction to Earthquake.

Causes of Earthquake.

How the Ground shakes?

Effects of Earthquake on Structures.

Examples.

Relationship & world wide distribution of earthquake and

volcanoes.

Earthquake and Bangladesh.

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Earthquake & Volcanism The planet Earth comprises irregular shaped

and varying sized plates, which constantly move at different speeds. To be precise, the plates drift over the mantle layer of the Earth. Consequently, magma is generated along the plate boundaries.

When the plates collide, move apart or slide each other, it leads to generation and accumulation of pressure (strain), which when released causes earthquakes. The strongest earthquakes are manifested during the plate collision, while the slowest earthquakes are observed when plates move apart from each other.

Similar to earthquakes, volcanism or volcanic activity is observed when the plates are divergent (move apart) or convergent (move towards each other). In such plate movements, the magma present in the plate boundaries may rise to the Earth's surface, leading to volcanic eruptions.. Divergent plates may cause long volcanic rifts, whereas convergent plates result in individual

volcanic eruptions.

WORLDWIDE DISTRIBUTION OF EARTHQUAKE AND VOLCANIC ZONES The close relationship between earthquakes and volcanic outbursts is evident from the maps depicting the locations prone to both phenomena. If you compare the maps that illustrate earthquake zones and volcanic zones, you will find them matching to each other. The main theory behind both these natural calamities lies in the plate tectonics.

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Interesting facts about Earthquakes in Bangladesh

THANK YOU.