Transcript Eliana
Made By: Eliana M. From Where: Anderson, Indiana What Is It: My Earthquake Presentation Dear Mr. President, My team and I, Eliana Monaghan, have fulfilled your request to answer the following questions: Where are the most recent earthquakes occurring, and are they more likely to occur in certain locations? Are there parts of the world that are more prone to them? Is there a relationship between earthquakes and volcanoes? What is causing the earthquakes? All of these questions are challenging, but reasonable. I, as lead scientist of the United States Geological Survey (USGS), was willing to accept this challenge. Many earthquake seem to occur near the Pacific Ocean. The reasoning behind this is because that is where a 40,000 kilometer chain of volcanic eruptions encircles the basin of the Pacific Ocean, also known as the Ring of Fire. The Pacific Ring of Fire has four hundred fifty-two volcanoes that are responsible for ninety percent of the world’s earthquakes. Eighty percent of the world’s earthquakes are some of the largest in the world. The Pacific Ring of Fire is home to the most active and dormant volcanoes in the world. Not all volcanoes are in the Pacific Ring of Fire, though. Multiple volcanoes also border plate boundaries. Although the Pacific Ring of Fire is responsible for the countless numbers of our world’s earthquakes, there does seem to be another pattern going on. According to the maps I have used for research, most earthquakes also occur along or near plate boundaries. Adjacent to plate boundaries are many faults. Faults are areas in the Earth’s surface where layers of displaced rocks have broken through the Earth’s crust. Since the layers of rock are unable to flow past each other with ease, it causes stress to build up in the rocks. Finally the rocks will have exceeded the strain threshold and cause potential energy to be released, creating an earthquake. Earthquakes are more likely to strike in either of those two areas, the Pacific Ring of Fire or plate boundaries. Some earthquakes can occur in completely different areas, but it is unlikely. The only way to tell where most earthquakes will take place in the future is by studying an area’s past. The past earthquakes that have come about in the Pacific Ring of Fire and near plate boundaries is numerous. I would have to say that plate boundaries and the Pacific Ring of Fire are the most prone areas to earthquakes. Both earthquakes and volcanoes are set off by plates suddenly shifting. The only difference is that earthquakes happen when a plate cracks. When the plate cracks, seismic waves send the tremors to the Earth’s surface. Volcanoes erupt when plates shift, allowing magma from within the Earth to rise to the crust. The crust will start to bulge from the pressure applied and eventually crack. Magma will be able to leak out of the break in the crust. Some legends have implied that the movements of giant, underground monsters are the cause of earthquakes, but I can assure you that is not the case. As I said before stress is applied to plates that are trying to get past each other and are unable to. Ultimately, the stress will make the plates start to bend. Strain will build up, breaking the plate. The break will end in shakes and quivers being sent to the Earth’s surface by seismic waves. If you want to know more about earthquakes or you have any other questions, I will be more then happy to provide another letter of information at your request. Contact me anytime, and let me know. I’m always up for another challenge. Thank you for your time and cooperation. My team and I enjoyed researching the required information. Sincerely, Eliana M. Lead Scientist of the United States Geological Survey (USGS) An earthquake is a violent shaking/trembling of the Earth’s surface. Stress is applied to plates that are trying to get past each other, but are unable to. The stress will cause the plates to bend, eventually breaking as the stress builds. Seismic waves will send tremors from the break to the Earth’s surface, creating an earthquake. Earthquakes occur mainly around plate boundaries or the Pacific Ring of Fire. The Pacific Ring of Fire is a chain of volcanic eruptions that encircle the Pacific Ocean basin. The 452 volcanoes in the Pacific Ring of Fire are responsible for 90% of the world’s earthquakes. Adjacent to plate boundaries are faults. Faults are areas in the Earth’s surface where layers of displaced rock have broken through the Earth’s crust. Description Magnitude Frequency per year Great Major 8.0+ 7.0-7.9 1 18 Large (destructive) Moderate (damaging) Minor (damage slight) Generally felt Potentially perceptible Imperceptible 6.0-6.9 5.0-5.9 4.0-4.9 3.0-3.9 2.0-2.9 less than 2.0 120 1000 6000 49,000 300,000 600,000+ Magnitude-the greatness in size or extent. Indiana is a possible high risk zone for earthquakes because there is a fault that goes through southwestern Indiana. The fault is known as the Wabash Valley Fault. The fault also goes through southeastern Illinois and northwestern Kentucky. The Wabash Valley fault is a normal fault. Earthquakes can be a very devastating experience for many people. Communities are destroyed. People become homeless. Others relocate with very little. Some people get trapped under the piles of rubble from the destruction of the earthquake. Family members and friends will mourn for their loss. Practice Drop, Cover, and Hold On. Choose a safe place in every room with a sturdy table/desk or against a wall where nothing can fall on you. Have at least three gallons of water per person. Make sure to have a first aid kit. Keep canned foods/can opener available. Possess protective clothing. Have a battery-powered radio, spare flashlights, and extra batteries. Now you’re informed. Take it seriously and be prepared.