Plz help or I might die!?

Question

I need to know, NEED to know, why are surface waves the most destructive waves in earthquakes???

Answer 1

Surface waves are analogous to water waves and travel just under the Earth's surface. They travel more slowly than body waves. Because of their low FREQUENCY, long DURATION, and large AMPLITUDE, they can be the most destructive type of seismic wave. There are two types of surface waves: Rayleigh waves and Love waves.

Rayleigh waves, also called ground roll, are surface waves that travel as ripples similar to those on the surface of water.They are slower than body waves, and supposedly can readily be seen during an earthquake in an open space like a parking lot where the cars move up and down with the waves.

Love waves are surface waves that cause horizontal shearing of the ground.They usually travel slightly faster than Rayleigh waves.

Answer 2

Body waves move through the inner part of the earth, while surface waves travel over the surface of the earth. Surface waves -- sometimes called long waves, or simply L waves -- are responsible for most of the damage associated with earthquakes, because they cause the most intense vibrations. Surface waves stem from body waves that reach the surface.

There are two main types of body waves.

* Primary waves, also called P waves or compressional waves, travel about 1 to 5 miles per second (1.6 to 8 kps), depending on the material they're moving through. This speed is greater than the speed of other waves, so P waves arrive first at any surface location. They can travel through solid, liquid and gas, and so will pass completely through the body of the earth. As they travel through rock, the waves move tiny rock particles back and forth -- pushing them apart and then back together -- in line with the direction the wave is traveling. These waves typically arrive at the surface as an abrupt thud.

* Secondary waves, also called S waves or shear waves, lag a little behind the P waves. As these waves move, they displace rock particles outward, pushing them perpendicular to the path of the waves. This results in the first period of rolling associated with earthquakes. Unlike P waves, S waves don't move straight through the earth. They only travel through solid material, and so are stopped at the liquid layer in the earth's core.


Click the play button to start the earthquake.
When P and S waves reach the earth's surface,
they form L waves. The most intense L waves
radiate out from the epicenter.

Both sorts of body waves do travel around the earth, however, and can be detected on the opposite side of the planet from the point where the earthquake began. At any given moment, there are a number of very faint seismic waves moving all around the planet.

Surface waves are something like the waves in a body of water -- they move the surface of the earth up and down. This generally causes the worst damage because the wave motion rocks the foundations of manmade structures. L waves are the slowest moving of all waves, so the most intense shaking usually comes at the end of an earthquake.

In the next section, we'll see how scientists can calculate the origin of an earthquake by detecting these different waves.

Answer 3

because they are on the top of the water as opposed to body waves which emanate from below..Surface waves can crash into builings bridges, etc..body waves are actually helpful because they can help seismologists find the epicenter of oceanfloor earthquakes.

Answer 4

Most property improvements are on the surface. And golly, WE live on the surface, too! Can you see where the correlation is, now? Best of luck.

Answer 5

because they are on the surface of land and can can do more harm than other waves

Answer 6

Hate to break the news to you, but you're gonna die anyway.

Answer 7

there is more to destroy on earth's surface than under it... duh.. :)