What are Seismic Waves? - PowerPoint PPT Presentation

What are seismic waves
1 / 30

  • Uploaded on
  • Presentation posted in: General

What are Seismic Waves?. Types of Waves. Compression wave (longitudinal) Transverse Wave Seismic Wave Body Waves Primary or p-wave Compression wave Secondary or s-wave Transverse wave Surface Love wave Rayleigh wave. Seismic Wave.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.

Download Presentation

What are Seismic Waves?

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript

What are seismic waves

What are Seismic Waves?

Types of waves

Types of Waves

  • Compression wave (longitudinal)

  • Transverse Wave

  • Seismic Wave

    • Body Waves

      • Primary or p-wave

        • Compression wave

      • Secondary or s-wave

        • Transverse wave

    • Surface

      • Love wave

      • Rayleigh wave

Seismic wave

Seismic Wave

  • 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.

  • There are several different kinds of seismic waves, and they all move in different ways. The two main types of waves are

    • body waves

    • surface waves

How seismographs work

How Seismographs Work

The pendulum remains fixed as the ground moves beneath it.

Typical seismogram

Typical Seismogram

Body waves

Body Waves

  • P Waves (compression wave)

  • The first kind of body wave is the P wave or primary wave. This is the fastest kind of seismic wave. The P wave can move through solid rock and fluids, like water or the liquid layers of the earth. It pushes and pulls the rock it moves through just like sound waves push and pull the air.

Primary waves p waves

Primary Waves (P Waves)

  • A type of seismic wave that compresses and expands the ground

  • The first wave to arrive at an earthquake

Stop and think

Stop and Think

  • Have you ever heard a big clap of thunder and heard the windows rattle at the same time?

  • The windows rattle because the sound waves were pushing and pulling on the window glass much like P waves push and pull on rock. Sometimes animals can hear the P waves of an earthquake. Usually we only feel the bump and rattle of these waves.

Body waves1

Body Waves

  • S wave (transverse wave)

  • The second type of body wave is the S wave or secondary wave, which is the second wave you feel in an earthquake. An S wave is slower than a P wave and can only move through solid rock. This wave moves rock up and down, or side-to-side.

Secondary waves s waves

Secondary Waves (S Waves)

  • A type of seismic wave that moves the ground up and down or side to side

Comparing seismic waves

Comparing Seismic Waves

Surface waves

Surface Waves

  • Move along the Earth’s surface

  • Produces motion in the upper crust

    • Motion can be up and down

    • Motion can be around

    • Motion can be back and forth

  • Travel more slowly than S and P waves

  • More destructive

  • Types:

    • Love

    • Rayleigh

Surface waves1

Surface Waves

  • Love Waves

  • The first kind of surface wave is called a Love wave, named after A.E.H. Love, a British mathematician who worked out the mathematical model for this kind of wave in 1911. It's the fastest surface wave and moves the ground from side-to-side.

Surface waves2

Surface Waves

  • Rayleigh Waves

  • The other kind of surface wave is the Rayleigh wave, named for John William Strutt, Lord Rayleigh, who mathematically predicted the existence of this kind of wave in 1885. A Rayleigh wave rolls along the ground just like a wave rolls across a lake or an ocean. Because it rolls, it moves the ground up and down, and side-to-side in the same direction that the wave is moving. Most of the shaking felt from an earthquake is due to the Rayleigh wave, which can be much larger than the other waves.



What is an earthquake

What is an earthquake?

  • Used to describe both sudden slip on a fault, and the resulting ground shaking and radiated seismic energy caused by the slip

  • Caused by volcanic or magmatic activity,

  • Caused by other sudden stress changes in the earth.

What causes earthquakes

What causes earthquakes?

  • Tectonic plates move past each other causing stress. Stress causes the rock to deform

What are seismic waves

Focus – point inside the Earth where an earthquake beginsEpicenter – point on Earth’s surface above focus

How do scientists calculate how far a location is from the epicenter of an earthquake

How do scientists calculate how far a location is from the epicenter of an earthquake?

  • Scientists calculate the difference between arrival times of the P waves and S waves

  • The further away an earthquake is, the greater the time between the arrival of the P waves and the S waves

Locating earthquakes

Locating Earthquakes

Locating earthquakes1

Locating Earthquakes

Locating earthquakes2

Locating Earthquakes

How are earthquakes measured richter scale

How are Earthquakes Measured? Richter Scale

How are earthquakes measured mercalli intensity scale

How are Earthquakes Measured? Mercalli Intensity Scale

Click Link for Interactive Demo http://elearning.niu.edu/simulations/images/S_portfolio/Mercalli/Mercalli_Scale.swf

Earthquake waves earth s interior

Earthquake Waves & Earth’s Interior

Seismic waves in the earth

Seismic Waves in the Earth



Formation of a tsunami

Formation of a Tsunami

Tsunami warning system

Tsunami Warning System

Now it is your turn

Now it is your turn!!

  • Click on the following link:

  • http://www.sciencecourseware.com/eec/Earthquake/EpicenterMagnitude/

  • Now start activity using handout at end of notes.

  • You must use the following code

    • For 3rd period use

      • 2113714

    • For 4th period use

      • 2113861

    • For 6th period use

      • 2113947

        Assignment due by Tues March 26 by end of class!

  • Login