To understand the impact of earthquakes, one should know certain basic facts about the earthquakes and how and why do they occur.
What is an earthquake?
In simple layman terms, an earthquake is a result of shaking of the earth or due to vibrations on the surface of the earth.
Why do earthquakes occur?
When two areas of the earth’s crust try to move in two different directions, pressure builds up due to the friction. When this pressure is released, it causes an earthquake.
How are earthquakes measured?
Earthquakes are measured on the â€œRichter Scale of 1 to 10â€. Each successive integer has a magnitude which is 10 times that of the lower integer and has 30 times more energy.
What is the focus and epicenter of an earthquake?
The point at which the earthquake happens below the earth is caked the focus. The point on the surface of the earth directly above the focus is known as the epicenter of the earthquake.
What happens when an earthquake occurs?
Earthquake has the capacity to destroy entire cities. Large scale destruction is caused by earthquakes as buildings collapse like nine pins. This can cause loss to life as well as property.
Where can an earthquake occur?
An earthquake can occur at any point on the earth wherever the fault line lies. It can also occur beneath the seas. Such earthquakes can generate tsunamis which are capable of much more destruction than the earthquake itself.
What are the effects of an earthquake?
The destructive capacity of the earthquake is tremendous and it can be broadly classified into two categories.
- Primary effects: The immediate damage caused by an earthquake which is characterized by collapse of buildings, bridges and other manmade structures. One point to remember here is that earthquakes do not kill anybody. It is only the debris from the collapsing buildings which do all the killing. This results in heavy loss to life and property. It may take years for a city to limp back to normal. Many families get devastated as they lose everything they possessed. People get scarred physically as well as mentally. Mental scars are the ones which are difficult to get rid of.
- Secondary effects: These are the after effects of an earthquake which can be listed as below.
- Fires: Earthquakes can cause bursting of gas and oil pipelines as well as electric cables which can become a major source of fire. At the same time water pipes too get broken and hence there does not remain any water supply to fight the fires. This causes the fire to spread and cause havoc.
- Tsunamis: Tsunamis are tidal waves that hit the coastline whenever an earthquake occurs deep under the sea. The shift in the tectonic plates causes the water to flow uncharacteristically towards the shore and the moment it hits land it takes gigantic proportions and has capacities to wash away entire cities in its wake.
- Landslides: Earthquakes in mountainous areas cause landslides which further compound the damage by hampering rescue operations.
- Disease and famine: As earthquakes strike, they break the water supply pipes and hence water supply gets cut off for long period of time. Lack of food, water and shelter causes diseases as well as famines. Now rescue operations and relief measures are conducted very soon by the administration, and hence the threat of famine is taken care of in recent times.
- Soil liquefaction: When earthquake strikes, soils with large water content are shaken up violently causing the land to sink and take buildings too with it.
These are the impacts an earthquake can have on the minds and lives of people.