Earth is made of 7 major tectonic plates and numerous secondary and

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Earth is made of 7 major tectonic plates and numerous secondary and tertiary plates that move towards each other, away from each other or slide past each other. The forces between the plates cause potential energy to be stored along the boundaries. When too much energy is stored along these boundaries, energy is released through the movement of these plates, which causes earthquakes. Every year, hundreds of thousands of earthquakes occur along the boundaries of these plates that vary in magnitude and intensity. In fact, most (not all), of earthquakes occur along tectonic boundaries, which help scientist and researchers to define and detect major and minor plates. The point on the surface of the earth at which the earthquake happened is known as the epicenter. Figure 1 shows the epicenters of earthquakes. The depth of the earthquake is known as the hypocenter. Figure 1. World Seismicity Map. Small dots are earthquakes of various depths which help outline the plate borders. When an earthquake happens, rays travel from the earthquake source throughout the earth’s interior at various velocities, which depend on the temperature, density, pressure, and phase composition (Figure 2). Seismic stations can capture this data, so that scientist can interpret data, and engineers can use data to solve problems that are created by earthquake events, such as building failure. Figure 2. A depiction of how compressional and shear waves propagate throughout the Earth’s interior at various angles. Notice the refraction in the outer core due to a change in compositional properties. So what is engineering? Engineering is the process of applying mathematical and scientific concepts to create and improve a design, in the most efficient and economical way possible. This final product must be tested under various conditions to determine the durability and effectiveness of the design. This testing process will help engineers to determine if further steps need to be taken in order to improve the design of the product, and if further alterations will exceed time and financial constraints. Specifically, earthquake engineers use seismic data as well as history of events in certain regions to simulate events such as tsunamis and earthquakes. They design structures such as bridges, houses, and skyscrapers, and test their performance in a series of rigorous tests. In general, earthquake engineers want to answer the question, “Under what environmental conditions and by what means will this structure fail?” . Figures 3a and 3b show two methods that simulate natural disasters (tsunamis, and earthquakes respectively). Figure 3a. Tsunami wave tank generator at Oregon State University Figure 3b. NEESwood shake table with six story structure atop. The NEES network features 14 geographically-­‐distributed, shared-­‐use laboratories that support several types of experimental work: geotechnical centrifuge research, shake table tests, large-­‐scale structural testing, tsunami wave basin experiments, and field site research. Earthquake engineering researchers and students have the opportunity through the NEES collaboratory of 14 experimental equipment sites and a robust cyberinfrastructure featuring online simulation tools to conduct more advanced research of designs, materials, construction techniques and monitoring tools. Research results will enable engineers to develop better and more cost-­‐effective ways of mitigating earthquake damage. NEES plays a major role in developing next generation earthquake and tsunami engineers, offering education, outreach and training for K-­‐16 students, graduate students, educators, and researchers. The NEESacademy is an excellent resource for teachers of all student ages to find engaging activities for classroom demonstrations or individual inquiry activities. Professionals may access illuminating reports on research projects and their impact or participate in quality seminars and webinars sponsored by NEES affiliated projects and professional partnerships. Make Your Own Earthquake is a new and exciting module that consists of K-­‐12 lesson plans, video and resource links, and instructions on how to obtain and build equipment. The Education, Outreach and Training team encourages you to explore and review our module. The concept behind this module is to not only teach students about earthquake engineering, but to suggest methods of how K-­‐12 teachers can incorporate engineering principles into their science lessons. The Education Outreach and Training Team would like to thank you for visiting our site! 
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