Seismic Waves

By: blazekid3

Definition

Waves that travel through the Earth, most often as the result of a tectonic earthquake, sometimes from an explosion.

Interesting Facts- Seismic Waves happen when earthquakes occur.

- Seismic Waves consists of three different waves.

- They are known as…..

- Primary Waves

- Secondary Waves

- Surface Waves

- Primary waves (P waves) travel the fastest and can go through any solid, liquid, and gas. The speeds of P waves depends on the material in which it is moving through. Also they called elastic waves.

- Secondary waves (S waves) are fast except they do not travel as fast as P waves. S waves travel through solids although they can’t go through liquids and gases. S waves speed up when they pass through denser material. It is also called a shear wave.

- Surface Waves (L waves) are the slowest seismic waves. These waves start off at the epicenter, and then move along and travel on the Earth’s center into the ocean. L waves cause the most damage because they twist and bend the Earth’s surface. Another name for surface waves are Love waves or Rayleigh waves.

- Seismic Waves can not be seen, but are able to be felt.

Some famous locations that seismic waves occur in large areas are in the west. The Seismic Risk in the United States of these three states are called California, Nevada, and Washington. Some places to the east of this area that seismic waves happen are Utah, Idaho, and Montana. South Carolina, Tennessee, Kentucky, Missouri, Arkansas, Rhode Island, and Vermont experience seismic waves as well.

Famous Locations

The areas in the brown is where

the major Seismic Risks

happen.

HISTORICAL INFORMATION

In 1975, a prediction was made by the Chinese that an earthquake was going to take place in their country that saved thousands of people. It was very accurate and from that time people thought about what would happen if they could do this all the time. Well, their results could be that people can be saved, buildings and cities could be planned to be made, and they would know where not to live or stay. Attempts have already been made in some cities where they have built and constructed earthquake-proof buildings. Scientists look forward to advance their capability and foresee earthquakes from happening. Seismic waves only come about because of these disastrous earthquakes. In 1893, the seismograph was invented by John Milne that could detect and measure seismic waves. The way a seismograph works is that there is a pen attached to a ball and it can record any information on paper because of the straight lines it makes. It makes the lines pertaining to the ground shaking and how much movement is happening. The higher the lines are, the stronger the wave is. This is measured in seismograms. Seismograph networks can also locate earthquakes on where they are already happening.

Connections and Additional Information

Connections to seismic waves are earthquakes because that’s what obviously causes seismic waves. Also, seismographs is a connection because this instrument shows how powerful these waves can be. In addition, seismic waves can also be connected to the Richter scale. This reason is because earthquake strength is calculated with this device. This is very similar to the seismograph because they both measure strengths of the earthquake and the seismic waves. Some additional information about seismic waves is that the scientists in China think that they can predict earthquakes by the change in the behavior of certain animals. For example, if an animal is out in the open and decides to look for shelter or go underground, this could mean that they are maybe trying to escape from the earthquake that results the seismic waves. Furthermore, they think that before a major earthquake strikes, speeds of P waves and S waves change so this is another way to predict them.

Hall, Prentice. Dynamic Earth. 2nd Edition. Englewood Cliffs, New Jersey: A Division of Simon & Schuster, 1994. Print.

http://www.britannica.com/EBchecked/topic/532925/seismic-wave

http://www.seismo.unr.edu/ftp/pub/louie/class/100/seismic-waves.html

Sources for Information

2 QUESTIONS

These are the two questions that are related to my topic.

What are the functions of the seismograph and how does it work?

What are the three different waves that seismic waves consist of and how fast do they each travel?