EARTHQUAKEEARTHQUAKE When the Earth Moves

L’ Aquila, Italy Town center before the April 6, 2009 earthquake.

L’ Aquila, Italy After 6.3 earthquake - 4,000 buildings collapsed

Italy is criss-crossed by two major faults. The African and European plates collide, creating a large fault right down the spine of Italy.

Earthquake plots in Italy from

In the streets of L’ Aquila Rubble of buildings all around

Searching for survivors Picking through the rubble looking for those trapped

Carrying the dead 292 people are believed to have died

Finding a survivor

Earthquake Diagram An earthquake occurs when the Earth’s crust moves along a fault. The movement creates seismic waves.

P-WaveP-Wave Compressional waves, arrive first, shake ground back and forth in same direction of wave, do little damage.

S-WaveS-Wave Secondary or shear wave, arrive second, shake ground back and forth perpendicular to direction of wave, cannot travel through liquid, more destructive than P-Wave.

L-WaveL-Wave Love or surface waves, found on or near the surface, move the ground up and down like something bobbing in the ocean, cause the most damage.

Earth’s interior affects path of waves. P-Waves are slowed and S-Waves cannot penetrate Earth’s core.

San Francisco quake killed over 3,000 people; fires consumed the city.

Alaska quake - powerful enough to bend train tracks.

Anchorage, Alaska Damage following Good Friday Earthquake

Chile earthquake - largest in known history; killed over 3,000; created tsunamis in California and Hawaii.

Indonesia quake created huge tsunamis devastating areas around Indian Ocean, killing over 250,000. Movement along fault estimated to be about meters.