Order from us for quality, customized work in due time of your choice.
An earthquake is the sudden vibration of the ground caused by movements of the Earths crust. These disasters originate from a focus point commonly located underground in a fault zone. A fault is the fracture found inside a tectonic plate where pressure builds up and exceeds causing a release of energy (Seismic Waves) that cause the tremble of an earthquake. Two plates may collide and create friction against each other, the rocks in between push together until they rupture from the built up pressure.
Shallow earthquakes can occur near or on the ocean floor and hence may lead to causing tsunamis. To be specific, when a continental plate being pulled below by an oceanic plate, it leads to bending the plate until it suddenly cant handle the pressure and snaps back with enough force to push excess seawater up. Consequently, the pushed seawater will spread to different directions and reach land hours later.
The country this article will focus on is Chile. Being a nation prone to earthquakes, its vital to instil awareness of the damage earthquakes and tsunamis may bring upon populated areas.
On average, about 18 major earthquakes occur per year, 8 000 unnoticed per day, 2 million minor per year and at least one of a magnitude of 8 or above. In the past five years, Chile has had a series of large earthquakes and tsunamis at magnitudes between 6.5 and 8.5. Out of the 10 earthquakes that have devastated Chile, seven brought tsunamis upon their coasts. An earthquake/tsunami in Iquique Offshore Tarapacá in 2014 with a magnitude of 8.2, resulted in 7 deaths. Another fatal tsunami at the same location in 2015 with a magnitude of 8.3 resulted in 15 deaths, and a recent earthquake in Coquimbo in January this year, at a magnitude of 6.7, had only 2 casualties.
Chile is located along a subduction zone called the Peru-Chile Trench. These recurring disasters mean the country is well-prepared when it comes to communication across cities and designing infrastructures able to withstand and leave less destruction. As developed the country is, certain areas are still in deep poverty. These small towns that the government has made few attempts at redeeming, whether it be education or employment wise, its a safe assumption that these places are at risk when earthquakes could occur.
EWS stands for Early Warning System. Its a chain of communication used between different nations across the world to receive seconds, minutes or hours of notice beforehand of approaching natural disasters. Countries are able to predict these disasters and evacuate targeted areas in time.
The EWS is a very helpful contribution during evacuations in Chile, preventing thousands of deaths. It works by using sensors placed near significant fault zones, detecting waves of higher frequency than surface waves that travel underground. Two kinds of waves are usually detected on the seismographs, P and S waves. Primary waves arrive first at the targeted area (before the earthquake) because theyre able to travel through both liquid and solid layers of the Earth. Secondary waves are felt during earthquakes and are slower at arriving due to its movement limited through only solid rock.
Depending on the distance from the sensors and Chile, the early warning arrival can come as late to seconds before the disaster. However, seconds are still vital to evacuations, immediate action can be made ranging from directing lifts to nearest floors and stopping trains. In recent years, besides educating students and citizens how to evacuate and pick up early warnings independently, the EWS has also been made available to mobile phones.
Benefits of the EWS include:
- Sending early warnings to the publics mobile phones helps let people evacuate quicker and inform others
- Death rates decrease drastically, compared to an earthquake of less magnitude in Nepal, hundreds of thousands of lives were lost without an organised EWS. Unlike Chile, the EWS saved 2 million lives.
- Buildings designs keep earthquakes in mind and become more concrete using information the EWS tracks
- Limitations/disadvantages of the system include:
- The government still needs to find time in peoples schedules to correctly train them on how to respond immediately after receiving seconds of notice from the EWS
- The timing when the warning arrives is very short
- There are sometimes false alarms when using only one seismograph, errors caused by noise, lightning and etc.
As movement in the earths crust continues to shift, its important to establish awareness of earthquakes and the EWS as a precaution. With each earthquake of tsunami that occurs in Chile, they learn from their mistakes and show progress in better organising evacuations to put less lives in danger. Scientists may not be able to prevent these unpredictable disasters, but they can evacuate and save more lives than lose through seismology.
Order from us for quality, customized work in due time of your choice.