Earthquakes

Earthquakes : 

Earthquakes Name- Bismay Nayak Class-VIII ‘B’ Roll no.-7 Subject-Chemistry Guided By- Anjana madam

Earthquakes : 

Earthquakes An earthquake (also known as a quake, tremor, or temblor) is the result of a sudden release of energy in the Earth's crust that creates seismic waves which causes shaking of the ground. The intensity of earthquake is measured in Richter scale. Seismograph is used to measure it. Earthquakes that scale more than 5-6 on Richter scale can cause great damage to life and property.

How earthquake occurs? : 

How earthquake occurs? Earth is divided into several layers of crust , mantle and core. Tectonic plates The crust is divided into several plates called Tectonic plates. These plates float on the mantle and keep on moving. When two plates going in opposite directions hit each other, they get interlocked creating great force. Due to the force some rocks give way and due to the sudden release of energy vibration is caused. These vibrations travel in the form of seismic waves causing an earthquake. The gap between two plates is known as fault. The point where rocks give way is called the focus and the point just above it on the surface is known as the epicenter.

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Fault, epicenter and focus Destruction caused by earthquakes

2010 Chilean earthquake : 

2010 Chilean earthquake The 2010 Chilean earthquake occurred off the coast of the Maule Region of Chile on February 27, 2010, at 03:34 local time , rating a magnitude of 8.8 on the moment magnitude scale, and lasting up to 90 seconds. It was strongly felt in six Chilean region (from Valparaíso in the north to Araucanía in the south), that together make up 80 percent of the country's population. Tremors were felt in many Argentine cities, including Buenos Aires, Córdoba, Mendoza and La Rioja. Tremors were felt as far north as the city of Ica in southern Peru (approx. 2400 km). The earthquake triggered a tsunami which devastated several coastal towns in south-central Chile and damaged the port at Talcahuano. Tsunami warnings were issued in 53 countries, causing minor damage in the San Diego area of California and in the Tōhoku region of Japan, where damage to the fisheries business was estimated at ¥ 6.26 billion (USD$66.7 million). The earthquake also generated a blackout that affected 93 percent of the country's population and which went on for several days in some locations. . The latest death toll as of May 15, 2010 is 521 victims (down from early reports on March 3 of 802).

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Epicenter of Chilean earthquake A destroyed building

April 2010 Sumatra earthquake : 

April 2010 Sumatra earthquake The April 2010 Sumatra earthquake was a 7.8 Mw earthquake that occurred on April 7, 2010, at 5:15 AM local time near Banyak Islands, off the island of Sumatra in Indonesia. A tsunami watch was issued according to the Pacific Tsunami Warning Center in Honolulu which was later canceled. A 40 cm surge was reported in the Banyak Islands an hour after the quake, along with 62 injuries. Power outages were reported throughout the province of North Sumatra as well as in Aceh.

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A destroyed building Epicenter of Sumatra earthquake

2010 Haiti earthquake : 

2010 Haiti earthquake The 2010 Haiti earthquake was a catastrophic magnitude 7.0 Mw earthquake, with an epicenter near the town of Léogâne, approximately 25 km (16 miles) west of Port-au-Prince, Haiti's capital. The earthquake occurred at 16:53 local time on Tuesday, 12 January 2010. By 24 January, at least 52 aftershocks measuring 4.5 or greater had been recorded. An estimated three million people were affected by the quake; the Haitian Government reported that an estimated 230,000 people had died, 300,000 had been injured and 1,000,000 made homeless. They also estimated that 250,000 residences and 30,000 commercial buildings had collapsed or were severely damaged.

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Epicenter of Haiti earthquake Destroyed Port-Au-Prince

2010 Yushu earthquake : 

2010 Yushu earthquake The 2010 Yushu earthquake struck on April 14, 2010, and registered a magnitude of 6.9 on Richter scale. It originated in Yushu, Qinghai, China, at 7:49 am local time. According to the Xinhua News Agency, 2,698 people have been confirmed dead, 270 missing and 12,135 injured of which 1,434 are severely injured. The epicenter was located in Rima village, Upper Laxiu township of Yushu County, in remote and rugged terrain, near the border of Tibet Autonomous Region. The epicenter is about 30 km from Gyêgu town or Jyekundo, the seat of Yushu County, and about 240 km from Qamdo. The epicenter was in a sparsely populated area on the Tibetan plateau that is regularly hit by earthquakes.

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Destruction caused by Yushu earthquake

2010 Elâzığ earthquake : 

2010 Elâzığ earthquake The 2010 Elâzığ earthquake was a 6.1 magnitude earthquake that occurred on 8 March 2010 at 04:32 local time. The epicenter of the quake was Başyurt in Elâzığ province, in eastern Turkey. Initial reports in global media said as many as 57 people had died. Reports in the Turkish media two days after the quake placed the death toll at 41. Later, the death toll rose to 42. Another 74 were injured, many after falling and jumping from buildings during the quake. A stampede through the streets led to further injuries.

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Epicenter of Elâzığ earthquake Destruction

Earthquake precautions : 

Earthquake precautions 1. If you are indoors during an earthquake, drop, cover, and hold on. Get under a desk, table or bench. Hold on to one of the legs and cover your eyes. If there's no table or desk nearby, sit down against an interior wall. An interior wall is less likely to collapse than a wall on the outside shell of the building. 2. Pick a safe place where things will not fall on you, away from windows, bookcases, or tall, heavy furniture. 3. It is dangerous to run outside when an earthquake happens because bricks, roofing, and other materials may fall from buildings during and immediately following earthquakes, injuring persons near the building. 4. Wait in your safe place until the shaking stops, then check to see if you are hurt. You will be better able to help others if you take care of yourself first, then check the people around you. 5. Move carefully and watch out for things that have fallen or broken, creating hazards. Be ready for additional earthquakes called "aftershocks." 6. Be on the lookout for fires. Fire is the most common earthquake related hazard, due to broken gas lines, damaged electrical lines or appliances, and previously contained fires or sparks being released.  8. If you are outside in an earthquake, stay outside. Move away from buildings, trees, streetlights, and power lines. Crouch down and cover your head. Many injuries occur within 10 feet of the entrance to buildings. Bricks, roofing, and other materials can fall from buildings, injuring persons nearby. Trees, streetlights, and power lines may also fall, causing damage or injury.

Earthquake-proof buildings : 

Earthquake-proof buildings No buildings so far have been made totally earthquake proof. Some systems that have been designed to reduce earthquake damage in buildings include-  Concrete/steel reinforcing Lightweight materials Energy absorbing systems (most common in skyscrapers) Earthquake proof buildings are built to be more flexible. This can be in terms of being able to sway without buckling, or they could have foundations that are able to roll with the earthquake. The advantages include being less likely to collapse and trap people inside or damage other nearby property.

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Earthquake-proof buildings

Conclusion : 

Conclusion In conclusion, education is society's best tool in minimizing the effects of earthquakes. Seismologists have instruments that record earthquake movement to further study the emerging patterns. Earthquake prediction, based on the time interval between body and surface waves, is still primitive, yet is promising. Engineers have also conducted research about building structure in relation to earth movement. Along with the benefits of possible earthquake prediction, the potential for social and economic disaster remains. Thank you