Earthquakes● Earthquake: a sudden and violent

shaking of Earth, caused by movements within the crust or volcanism

● Ex. San Francisco Earthquake in California

EarthquakesEpicenter - The point directly above the focus or source of the earthquake. (Often described using the largest nearby city)Magnitude - Amount of energy released from the earthquake. (Often described using a number)

Ex) Picture on the right.Honshu Japan is the epicenter.7.3 is the magnitude.

Tsunamis● Tsunami: a large, long sea wave resulting from

an earthquake, submarine landslide, or other disturbance

● 90% of all tsunamis occur in the Pacific Ocean

Solutions to Earthquakes● Seismology: scientific study of

earthquakes and the movement of seismic waves

● Seismic Activity: the type, frequency, and size of earthquakes that happen over a period of time in a certain area

● Seismograph: the instrument used to detect and record earthquakes

Solutions to Tsunamis● Seismographs ● Computerized offshore buoys (measure

changes in wave height)● System of sirens on the beach (to alert

people of potential tsunami danger)