Earthquakes Part 2 Remember earthquakes usually occur along

Earthquakes Part 2 Remember- earthquakes usually occur along faults in the earth’s lithosphere. (San Andreas Fault) - Normal Fault - Reverse Fault - Strike Slip Fault

. Remember- Richter Scale (1 -10) strength (magnitude is the strength of the quake) - Mercalli Scale (I – XII) damage -80% of earthquakes in the world happen along the outside circle of which plate? Called the …?

. -- I fell into a burning Ring of Fire….

. Earthquakes release Energy Quake energy travels in waves. Think of……. Throwing a rock into a lake ……. Stretching a slinky The energy of an earthquake travels as seismic waves. Even small seismic waves can be detected as they travel around the world. The detectors are called seismometers.

Ancient seismometer (seismograph) from China. Froggys and Dragons!

. . Modern Seismometer (seismograph)

• All quakes start beneath the surface of the earth. The focus of the quake is the point underground where rocks first start to move. • The epicenter is the place on the surface above the quake. Earthquakes are usually named for this spot. • Shallow quakes cause more damage than deep quakes. .

• Remember: quakes travels as waves…. Sound waves, water waves, slinky waves. The waves carry the energy, whether sound, water, or earthquake power…. • Earthquakes produce 3 kinds of waves. 1. Primary Waves ( P )- these are the first waves. They travel at about 3 miles per second through the earth. P waves move by pushing together and then pulling apart. Like a slinky.

. 2. Secondary Waves-( S ) – these are the second waves to arrive after an earthquake. They start at the same time as the P waves but are slower. -Motion is up and down or side to side. Cannot travel through liquid or air.

. Earthquake waves helped to discover what the layers of the earth were made of.

3. Surface Waves – these are the seismic waves that move along the surface of the earth. They make the ground roll up and down or shake from side to side. They cause the biggest ground movement and make the most damage. .

Earthquake Damage.

Earthquake Damage.

Earthquake Damage Tsunami Waves.