Earthquakes

What is an earthquake?

In an earthquake, the ground in which we stand on shakes due to blocks of earth passing on another. Large sections of the earth’s crust, tectonic plates, have edges that are marked by faults, and when these fault lines pass each other, or collide, it causes the plates to shake.
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How are earthquakes hazardous to humans, and why should they be a concern to us?

When the plates shake due to collision, the shock waves are extremely powerful. The shock waves are hazardous to humans due to the fact that they can be powerful enough to alter the Earth’s surface by thrusting up cliffs and also opening up huge cracks in the ground. When shock waves are powerful enough to alter the Earth’s surface, concerning hazards include the collapsing of man-made structures such as tall buildings, destructing power and gas lines which can lead to fires, landslides, snow avalanches, and tsunamis. All of these are a concern to the well being of people and property in the area.

What regions are most vulnerable to earthquakes?

Japan is at the top of the list of the earthquake prone areas due to the subduction of the Philippine Sea plate beneath the Okinawa plate and Amurian plate. When these plates collide, Japan endures intense earthquakes. India is also another place that is vulnerable to earthquakes. Indian tectonic plates move at the rate of 47 mm every year and because of such movement, India has been devastated by earthquakes. In American, California is prone to earthquakes because of its positioning in relation to the Pacific Plate and the North American Plate. Any area can endure an earthquake based off of pieces of the earth movement, and it is important to be informed and prepared no matter where you live.

Measurement of Earthquakes

Earthquakes are recorded by instruments called seismographs which have their bases in the ground, and a heavy weight that hangs freely. When the ground shakes, the base of the seismograph shakes too, but the hanging weight does not. The string that the weight hangs from is what absorbs the movement, and the difference in position between the shaking part and the still part of the seismograph is what is recorded. Seismographs determine how large the earthquake was. A line that does not bounce up and down very much means that the earthquake was small, but if it bounces up and down a lot, then the earthquake was larger, the size of an earthquake is its magnitude. The magnitude of an earthquake is measured using the Richter scale which is numbered 0-10.

Examples of Earthquakes

On March 11, 2011, a deadly earthquake hit Japan. It was measured to have a magnitude of 9, and it was the trigger of a massive tsunami. It began at 2:46 pm and lasted six minutes. The shaking centered on the seafloor 45 miles east of the Japanese Island, Tohoku. The number of confirmed deaths is 15,891, meanwhile 2,500 people are still reported missing. Along with horrible sadness and destruction for the people of Japan, it altered the land significantly. Two examples of the alteration of the land are the facts that 250 miles of Japan's northern Honshu coastline dropped by 2 feet, and Japan's main island of Honshu was moved eastward by 8 feet. Not a day goes by that the Japanese don’t remember this horrific event. A more recent earthquake with the magnitude of 8.1 occurred in Nepal on April 25th, 2015. The natural disaster took more than 8,000 lives and left more than 21,000 injured. The city of Kathmandu received the most destruction, but the disaster was felt in all surrounding areas where many people were sadly left homeless.


How to protect yourself from earthquakes

Earthquakes are an aspect of nature that are unpredictable. There are no ways to prevent earthquakes, but if you live in an area at risk for earthquakes, there are things that you can do to reduce the chances of injury. It is important to make sure that your home holds a strong structure, and you should be cautious of things in your home that would possibly fall over and break due to the shaking of the ground. It is good to have things lower to the ground and not put breakable things in places where they might fall. Also it may be a good idea to put together a supply kit including a flashlight in case the power goes out. When an earthquake begins to occur, it is important to remain calm, take cover, and stay close to your family and pets.
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