Bellwork 11/18/14 Be prepared to go over this chart together and turn in HW in black tray Normal Faults What Happens? Type of Boundary? Picture Examples… Tension, compression, or shearing? Reverse Faults Strike-Slip Faults

Measuring Earthquakes The energy from an earthquake travels as “seismic waves” which are vibrations caused when the fault shifts, and they can travel in all directions All earthquakes start below Earth’s surface. The “focus” of an earthquake is the point underground where rocks first begin to move. Seismic waves travel outward from the earthquake’s surface. The “epicenter” is the point on Earth’s surface directly above the focus. A “seismograph” is an instrument that constantly records ground movements.

Three Main Types of Waves Primary-can move through solids, liquids and gases 2. Secondary-can only move through solids 3. Surface-move along Earth’s surface

Activity Questions In both P and S waves, who was the focus? Did we have an epicenter? Justify Who felt more of the energy? Which waves were faster? Would surface, P, or S waves cause the most destruction? Why? What is the difference in the movement of the waves? P vs. S