What Is An Earthquake?

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What is an earthquake?

If the recognition of Lisa Wald "Green Frog News"

An earthquake is what happens when two blocks of land suddenly pass each other. The surface is called slip fault plane or fault. The location below the surface of the earth where the earthquake starts is called the hypocenter, and the location directly on the surface of the Earth is called the epicenter.

Sometimes an earthquake has foreshocks. These are smaller earthquakes that occur at the same place as the major earthquake that follows. Scientists can not see an earthquake is a shock until the larger earthquake happens. The largest earthquake is called the principal mainshock. Mainshock always aftershocks that follow. These are smaller earthquakes that occur later in the same place as the mainshock. Depending on the size of the main shock, aftershocks can continue for weeks, months and even years after the main shock!

What causes earthquakes and where they occur?

The Earth has four main layers: the inner core, outer core, mantle and crust. (Figure 2) The crust and upper mantle is a thin skin on the surface of our planet. But this skin is not all in one piece - it is composed of many pieces like a puzzle covering the surface of the earth. Not only that, but these puzzle pieces keep slowly around, slipping each other and bumping into each other. We call these puzzle pieces of plate tectonics, and the edges of the plates is called plate boundaries. The plate boundaries are composed of many errors, and most earthquakes worldwide occur on these faults. Since the edges of the plates are rough, they get stuck while the rest of the plate continues to move. Finally, when the plate is moved far enough, the edges off one of the errors and there is an earthquake.

Why the earth move when there is an earthquake?

Although the edges of defects are linked, and the rest of the block is moving, the energy that would normally get blocks slide past each other, put. When the force of moving blocks finally overcomes the friction of the jagged edges of the fault, and it takes off, all that stored energy is released. The energy is released from the error in all directions in the form of seismic waves like ripples on a pond. The seismic waves shake the ground as they move through it, and when the waves reach the surface of the Earth, they shake the earth and everything on it, like our homes and ourselves!

How earthquakes recorded?

Earthquakes are recorded by instruments called seismographs. The record they make is called a seismogram. The seismograph has a base which firmly establishes the ground and a heavy weight hanging freely. When an earthquake shakes the ground, the base of the seismograph shakes too, but the weight was not suspended. Instead, spring or string hanging down to absorb any movement. The difference in position between the party to shake off the seismograph and the stationary part are recorded.

How do scientists measure the size of earthquakes?

Size depends on the size of the earthquake fault and the amount of slip on the fault, but it is not something that scientists can simply measure a measuring tape since faults are many kilometers below the earth's surface. So how do you measure an earthquake? Using a seismogram seismograph recordings made on the surface of the country to find out how a large earthquake. Short sinuous wiggle is not much: a small earthquake, and a long sinuous line wiggles a lot of a large earthquake. Length of the wiggle depends on the size of the defect, and the move depends very much on the bike.

The size of the earthquake is called its magnitude. There is an order of magnitude of each earthquake. Scientists also talk about the intensity of the shock of an earthquake, and varies depending on where you are during the earthquake.

How can scientists say the quake hit?

Seismograms to be useful for locating earthquakes too, and be able to see the P wave and S wave is important. You learned how P and S waves shake the ground of each in different ways as they travel through it. P waves are faster than S waves, and this is what lets us know where it was an earthquake. To understand how this works, we compare P and S waves to lightning and thunder. Light travels faster than sound, so that during a lightning storm will first see, then you hear the thunder. If you are close to the lightning, thunder boom just after the flash, but if you're away from the rays can have several seconds before hearing thunder. Then there is the storm, the longer it takes between lightning and thunder.

P waves are like lightning, and S waves are like thunder. P waves travel faster and strike the country in which they are first. Then the S-wave and shake the ground too. If you are close to the earthquake, the P wave and S will be one after the other, but if you're far away, there's more time between the two. By examining the time between P and S waves recorded seismogram seismograph researchers can tell you that the earthquake in that position. However, they are not able to tell which direction an earthquake seismograph, or how far it was. If you draw a circle on a map of the station, where the radius of the circle is a specific distance from the earthquake, they know that the earthquake is located in a circle. But where?

Then the scientists used a method called triangulation to determine exactly where the earthquake was (Fig. 6). This is known as triangulation of a triangle has three sides, and it takes three seismographs to locate an earthquake. If you draw a circle on a map in three different seismographs where the radius of each is the distance from the station and the earthquake, the intersection of three circles is the epicenter!

Scientists can predict earthquakes?

No, and it is unlikely that will ever be able to predict them. Researchers have tried various ways to predict earthquakes, but none have succeeded. On any particular fault, scientists know it will be another earthquake in the future but have no way to tell when it will happen.

Is there such thing as earthquake weather? Maybe some animals or people say when an earthquake is about to blow?

These are two questions that have not yet definitive answers. If the weather affects the frequency of earthquakes, or if some animals or people can tell when an earthquake comes, you still do not understand how it works.