Earthquakes

pramalkumarsamanta By pramalkumarsamanta, 27th Apr 2015 | Follow this author | RSS Feed | Short URL http://nut.bz/2zqwaeht/
Posted in Wikinut>Guides>Emergency Preparedness>Earthquakes

Earthquakes causes a general panic among the masses of the area. Whenever earthquake occurs, it is presumed that the affected peoples face a tremendous psychological shock without knowing its magnitude , loss of lives and property. It causes tremors when it strikes the surface of the earth either in severe form or in mild form.

What is earthquake and its causes /

An earthquake is the shaking and vibration at the surface of the earth caused by energy being released along a fault plane,at the edge of a tectonic plate or by volcanic activity.
Earthquakes are caused by the movement of earth's outer layer( the crust and a portion of the upper mantle),the outside layer of the earth is split into tectonic plates which are moving slightly due to the movement of magma in the layer below. This causes plates to squeeze together,move apart and slide alongside each other.
earthquakes are classified into two types; a) Inter plate earthquakes - these earthquakes occur on tectonic plate boundaries where the tectonic plates are moving towards each other or sliding alongside each other.Inter plate earthquakes are common for countries such as japan,New zealand and the west coast of the United States which are located on tectonic plate boundaries. Large earthquakes are usually inter plate earthquakes.
b) Intra plate earthquakes- these earthquakes occur in the middle of tectonic plates on fault zones where the pressure of the tectonic plate being squashed and forced to move builds up and is released through the cracks in rocks associated with faultzones,resulting in an earthquake . As Australia is located in the middle of a tectonic plate, The Australians are less susceptible to larger earthquakes, however damaging earthquakes can still occur on fault zones.

Earthquake magnitude

Earthquake magnitude :The size of an earthquake is referred to as its magnitude on a Richter scale from 1 to 10. Magnitude as low as1 are measured in mines due to its rock bursts and the maximum magnitude possible is less than 10.For every unit in magnitude, there is roughly thirty-fold increase in the energy released.For instance, a magnitude 2.0 earthquake releases about 30 times more energy than a magnitude 1.0 earthquake, while a magnitude 3.0 earthquake releases 900 times (30x30) more energy than a magnitude 1.0
In Australia ,seismologists prefer the use of the moment magnitude scale, which calculates the magnitude of an earthquake based on physical properties such as the area of movement(slip) along the fault plane. The impacts of earthquake depends on its rate of magnitude .The maximum magnitude from 9.0 to 4.9 in Richter scale causes extensive damage,waves seen on the surface of the ground ,objects thrown into air..etc whereas the less magnitude from 4.8 to less than 3.4 in Richter scale causes the tremors felt by many people ,windows rattle,dishes disturbed, standing cars rock etc.

conclusion

In recent times two successive tremors, one on 25th April 2015 and on 12 th May 2015 were felt in Nepal and across north and east India, a quake devastated the neighbouring country and affected parts of India. The aftershocks measured 7.9 and 7.3 on Richter scale respectively --the epicenter was kodari,around 80 km east of Kathmandu.
In India,besides Delhi,the tremors were also felt in Lucknow and Jaipur.And in Bihar where more than 50 people died,the tremors were pronounced and went on for several minutes. In Delhi and Kolkata metro services were stopped temporarily.
!Yesterday's earthquake which measured 7.3 on Richter scale killed more than 2400 people in Nepal and 62 in India and led to widespread devastation.
Thousands of people were displaced in Nepal ,roads developed huge cracks, old buildings were flattened.The aftershocks remained mild, panick stricken people spent the night under the open sky.
The worst quake to hit the Himalayan country in 80 years also triggered a deadly avalanche that buried a part of the base camp for climbers bound for Mount Everest.19 bodies have been recovered so far ,61 people have been injured, five others died below the base camp.
All reputed international relief organizations and rescue teams have been pressed into service with their full resources so that the affected people may restore their normal life..

Tags

Ear, Earthquake, Earthquake Magnitude, Himalayancountry, Interplate Earthquake, Intraplate Earthquake, Magma, Mount Everestake, Richterscale, Seismologists, Tectonicplate, Volcanic Activity

Meet the author

author avatar pramalkumarsamanta
I am a retired government officer.I am a postgraduate in life sciences, I have a passion for writing on any topic.

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Comments

author avatar Kingwell
14th May 2015 (#)

I feel bad for these people and I hope that citizens of the world everywhere do their part to help. Blessings.

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author avatar pramalkumarsamanta
14th May 2015 (#)

Thanks for sharing his views.

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