It is a natural calamity which has devastating after effects. Thousands of lives are lost with a lot of damage done to the affected area. Sadly, it is something that is bound to happen. Earthquakes are inevitable and hence, governments all over the world have come up with pre-cautionary measures, to minimize the loss of lives as well as the damage in such earthquake prone areas.
What is an earthquake?
An earthquake is the sudden shaking of earth’s crust, this sudden shaking is caused by the tectonic plates.
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How does an earthquake occur?
The interior of the earth is made of several layers. The outermost layer is called the crust. The crust is not one single cover but, is made of several pieces. These pieces are called plates. The plates under the ocean are termed as oceanic plates and the rest are termed as continental plates. A tectonic plate (also called lithospheric plate) is an irregularly shaped slab which is composed of both continental and oceanic plates.
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Earthquakes are usually caused when rock underground suddenly breaks along a fault. This sudden release of energy causes the seismic waves. Seismic waves are the waves of energy caused by the sudden breaking of rock within the earth or an explosion. They are the energy that travels through the earth and is recorded on seismographs. The emission of such waves makes the ground shake.
Earthquakes generate three types of seismic waves: P (primary) waves, S (secondary) waves and surface waves. Both P and S waves penetrate the interior of the Earth while surface waves do not. Due to this, P and S waves are also known as “Body waves”. Surface waves arrive last and are the least interesting to seismic topographers because they don’t penetrate deep inside the Earth and hence, are not very resourceful.
When two blocks of rock or two plates are rubbing against each other, they stick a little. They don’t just slide smoothly. The rocks catch on each other. The rocks are start pushing against each other, but not moving which generates pressure between them. After a while, the rocks break because of all the pressure that’s built up. When the rocks break, as a result, the earthquake occurs. During the earthquake and afterward, the plates or blocks of rock start moving, and they continue to move until they are stuck again. The spot underground where the rock breaks is called the focus of the earthquake. The place right above the focus (on top of the ground) is called the epicentre of the earthquake.
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Since the plates which make up earth crust are constantly in motion, building up of strain must also be continuous event. As a result, the need for its release is also be frequently felt. Fortunately,95% of these earthquakes are very minute and doesn’t cause any serious damage.
Major earthquake prone countries in the world
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- Japan
Japan tops the list of the earthquake-prone areas in the whole world. Japan’s physical geography and its positioning along the Pacific Ring of Fire makes it very prone to earthquakes as well as to tsunamis. The Ring of Fire is a tectonic plate in the Pacific Basin that is responsible for 90% of the world’s earthquakes and 81% of the world’s strongest quakes.Moreover,it is also home to 452 volcanoes, making it the most vulnerable geographic location in terms of natural disasters.
- Nepal
Nepal is also a major disaster-prone country. Natural disasters cause a havoc almost every year in Nepal. It is one of the most seismically active regions in the world. The mountains bordering Nepal are built as a consequence of the Indian tectonic plate driving under Central Asia.
- India
India also has been a victim of some big scale earthquakes due to the movement of the Indian tectonic plate. Due to the frequent movement of Indian tectonic plates, India is also susceptible to Earthquakes.
- Ecuador
Ecuador has several active volcanoes making it a very vulnerable site for high- magnitude earthquakes. The country lies within the seismic zone between the South American plate and the Nazca plate. Earthquakes in Ecuador are generally occurred due to two reasons: Movement on the subduction interface along the plate boundary. Secondly, from deformation within the South American and Nazca Plates and those are associated with active volcanoes.
- Philippines
Philippines lies on the edge of the Pacific plate, which is a seismic zone. Manila, the capital of Philippines, is very prone to earthquakes and volcanic eruptions. It is very close to the Pacific Ring of Fire, making it pone to earthquakes and volcanic eruptions. Moreover, the danger of quakes increases due to its soft soil, which can result in ground liquefaction.
At present, earthquake prediction is insufficiently precise to provide the civilians with sufficient advance warning. For this reason, adequate preparedness and assistance is a must in an earthquake-prone area.
- Evaluate your home’s earthquake resilience and improve it through steps such as fastening down furniture and putting anti-shatter coatings on glass windows. Moreover, many modern infrastructures in earthquake-prone areas are designed keeping in mind, the sensitivity of such areas.
- You should have at least three days’ worth of drinking water and foodstuffs stockpiled. You should also have radios and flashlights prepared. Hence, a bag should always be prepared for such things.
- Get to know the people in your community better by getting actively involved in community disaster training. This is very helpful, especially for young ones.
- Never panic and keep your mind as calm as possible, it helps you work efficiently in the hour of need.