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What Is Seismology??

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Introduction

What Is Seismology?? The study of earthquakes and the structure of the earth, by both naturally and artificially generated seismic waves. An earthquake is defined as the vibration of the Earth's surface by sound or shock waves usually generated by the energy released from rocks rupturing under stress or by friction between moving rock materials at or mostly below Earth's surface. A seismologist is a scientist who studies earthquakes and seismic waves. CHAPTER 1 - What Are Seismic Waves? Seismic waves are the waves of energy caused by the sudden breaking of rock within the earth or an explosion. They are the energy that travels through the earth and is recorded on seismographs. How Are Seismic Waves Recorded? A seismometer records the vibrations from earthquakes. Mechanical versions work by way of a large mass, freely suspended. In the example on the left, a rotating drum records a red line on a sheet of paper. If the earth moves (in this case from left to right) the whole machine will vibrate too. However, the large mass tends to stay still, so the drum shakes beneath the pen, recording a squiggle! ...read more.

Middle

At the plate boundaries of an oceanic and continental plate, the oceanic plate subducts under the continental plate causing an earthquake. This subduction causes off shore trenches, which is where the sea is at its deepest. As the oceanic plate subducts beneath the continental plate, it begins to melt as it enters the hot mantle, producing magma. Volcanic chains can be formed from the fold mountains due to the subduction but that is only if there is a way for the magma beneath the earth surface to reach the ground surface, for example a crack. We know that due to the waves travel times, they cannot be moving through the earthy in a straight line. At a constructive or transform plate boundary, two plates slide side by side past each other in opposite directions. The forces exerted on either plate contribute to the rock style found there. The earth is structured as follows: The crust is very thin (about 20km or so), and the mantle has the properties of a solid but can flow very slowly. The core accounts for just over half the earth's radius and it is made from iron and nickel. ...read more.

Conclusion

a continental plate. When this happens, volcanoes and earthquakes occur. Trenches and fold mountains are also formed. 3. Conservative plate boundaries: Conservative plate boundaries occur when two plates slide past each other. When this happens, severe earthquakes can occur. 4. Collision plate boundaries: Collision plate boundaries occur when two continental plates move towards each other. When this happens, earthquakes occur and Fold Mountains are formed. CONCLUSION Seismic waves can be both very useful and very dangerous at the same time. Seismic waves can teach us so much about the Earth we live in. Plate tectonics can also teach us so much but can also be dangerous as they can cause earthquakes, volcanoes, and other natural disasters. Plate tectonics can teach us about the earths past and also what will happen to the earth in the future. Seismology has given many scientists ideas on how the Earth is structured. They have used the seismographs to figure out the differing effects of P and s-waves, and how they go through the earth, determining their behaviours. Scientists to discover the effects on and at plate margins used theories about plate tectonics. Because of volcanic eruptions and sever earthquakes, the Earth's crust is now considered to consist of several large slabs of rock and some smaller ones, called tectonic plates. Seismology is an advanced scientific research. ...read more.

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