An earthquake is a sudden vibration of the Earth’s surface. It’s also called a quake or tremor. Earthquakes can range in magnitude from those too weak to be felt to those powerful enough to hurl people around and demolish entire cities. But what are the causes of earthquake? A region’s seismicity or seismic activity relates to the number, kind, and size of earthquakes that occur throughout time.

So far, India has seen sixty-two earthquakes. The first documented earthquake in India occurred on June 6, 1505, at Saldang, Karnali Zone. The most recent one occurred on January 31, 2018, in India, affecting Kashmir, Pakistan, Afghanistan, and Tajikistan.

A Richter’s scale is used to determine the magnitude of an earthquake, and a seismometer monitors the vibrations produced by an earthquake. It plots the vibrations on a seismograph. The Richter scale is used to determine an earthquake’s intensity or magnitude. Earthquakes hitting 7 or 8 on the Richter scale can be devastating. Let’s read more about what are the causes of earthquake.

Where do Earthquakes Occur?

Earthquakes occur along faults, which are where tectonic plates collide. The Pacific Ocean’s rim accounts for around 80% of earthquakes. The area, known as the Ring of Fire due to its abundance of volcanoes, serves as a meeting point for numerous tectonic plates.

California is also prone to earthquakes due to its location on the Pacific and North American tectonic plates. Temblors occur when these two plates grind against one another. Approximately two-thirds of this displacement occurs along the San Andreas Fault.

Another large earthquake zone in the United States is the New Madrid Seismic Zone, which includes Missouri, Arkansas, Tennessee, Kentucky, and Illinois.

What are the Causes of Earthquake?

The tectonic plates, which consist of the Earth’s crust, are constantly moving. Friction can impede the movement of these plates in fault zones, causing pressure to build up over time. When the force of movement eventually overcomes the friction, portions of the crust abruptly crack or shift, releasing pent-up pressure as seismic waves. This is a naturally occurring earthquake, often known as a tectonic earthquake.

While tectonic earthquakes can occur anywhere on the planet, the bulk of significant earthquakes—about 80 per cent—occur in the circum-Pacific seismic belt, which runs along the Pacific rim. The Alpide belt, which stretches along Eurasia’s southern boundary through the Himalayan Mountains, Sumatra, and Java, and the Mid-Atlantic Ridge, which runs along the Atlantic Ocean’s floor, are two more areas where earthquakes occur frequently.

When an earthquake happens, several types of energy waves are produced. The first detectable waves are “P waves” or “primary waves”. Compression waves push and pull as they pass through rock and liquid. The successive waves to be recognised are called “S waves” or “secondary waves.” These waves only go through rock. They move up and down or sideways, perpendicular to the wave’s direction of travel.

Surface waves follow P and S waves and travel along the Earth’s surface, causing the most damage. They are divided into two types: Love waves, which are faster and move the ground from side to side, and Rayleigh waves, which roll on the surface of oceans and lakes.

Factors Contributing to Earthquakes

Here are some factors explaining what are the causes of earthquake:

Also Read: Environmental Changes And Their Role In Natural Disasters

How to Measure Earthquakes?

Every day, approximately half a million earthquakes shake the Earth. Typically, the quake is too little, too far beneath the surface, or too deep on the bottom to be felt. Some, however, are so powerful that they can be felt from thousands of kilometres away. The epicentre is the location on the surface immediately above where an earthquake begins. Seismic waves are ripples that propagate outward from the epicentre. This creates vibrations that people can feel, sometimes far away from the epicentre.

Their magnitude determines how far away people can feel their vibrations. Scientists calculate the magnitude based on the strength and duration of the earthquake’s seismic waves. The greater the number, the stronger the earthquake: A magnitude 3 to 4.9 earthquake is classified as small; 5 to 6.9 is moderate to strong; 7 to 7.9 is major; and 8 or more is an exceptionally powerful temblor.

As the crust settles following an earthquake, another tremor known as an aftershock may occur. Aftershocks are often less intense than the initial quake but can still be very strong.

Consequences of an Earthquake

An earthquake can inflict widespread damage to infrastructure and human life. The most common type of damage caused by earthquakes is building collapse. Let’s look at some consequences.

1. Human Life, Poverty: The loss of human life is the saddest result of an earthquake. A big earthquake in densely populated areas can claim thousands of lives. An earthquake can also severely destroy a region’s economy and interrupt essential services, resulting in long-term poverty for those who reside there.

2. Environmental Destruction: An earthquake can cause landslides, tsunamis, and other environmental harm. It can also pollute and taint water sources, resulting in the loss of valuable ecosystems and habitats.

3. Economic Effects: Earthquakes can have terrible economic consequences. Earthquakes can devastate infrastructure, disrupt supply systems, and induce inflation. They can also lead to higher living costs and lower productivity.

4. Other Natural Disasters: Earthquakes can also cause other natural calamities, such as volcanoes and tsunamis. These disasters can inflict considerably greater devastation and loss of lives.

Earthquake Management

Earthquake management coordinates and manages a crisis’s humanitarian aspects, including resources and duties. The idea is to reduce earthquakes’ damaging impacts.

• Risk Recognition: Recognising risk is the first step in earthquake management. It entails identifying sensitive places and analysing the possible damage that an earthquake may produce.
• Prevention and Preparedness: Preventing and preparing for earthquakes can minimise damage. This includes modifying vulnerable structures, educating people on what to do during an earthquake, and implementing a well-organised emergency response plan.
• Recovery and Reconstruction: Recovery and reconstruction are essential following an earthquake. This includes repairing damage, restoring infrastructure, and assisting individuals in reconstructing their lives.

In conclusion, earthquakes can have a wide range of repercussions, including human fatalities and environmental harm. They can also have economic consequences like higher inflation and lower productivity. As a result, it is critical to prepare for earthquakes before they occur. While there is no way to prevent earthquakes, there are measures to reduce their consequences.

Also Read: World’s Most Active Earthquake Zones