why some earthquakes cause more damage than others? Do Now!!! Infer... why some earthquakes cause more damage than others?

Section 5.2: Features of Earthquakes!!! Objectives: You will learn to explain how earthquake energy travels in seismic waves. You will learn to distinguish among primary, secondary, and surface waves. You will learn to describe the structure of the Earth’s interior.

Earthquake Information!!! focus interior _______ – the point in Earth’s _________ where energy ________ occurs. Seismic _______ are produced and move _________ from the _______. release waves outward focus

3 Types of Seismic Waves!!! 1. Primary (P) Waves __________________ 1. Primary (P) Waves 2. Secondary (S) Waves 3. Surface Waves

fastest particles back forth same wave 1. Primary (P) Waves fastest particles Travel the _______ and cause rock _________ to move _____-and-______ in the ______ direction the ______ is moving back forth same wave

slower primary right rock waves 2. Secondary (S) Waves slower primary Travel ________ than _________ waves and cause _____ particles to move at ______ angles to the direction of the _______ right rock waves

3. Surface Waves surface side side 2 Types: 1. Love (L) Waves Form at Earth’s ________ and cause an elliptical motion with some _____-to-_____ motion of rock particles (causes the most damage) side side 2 Types: 1. Love (L) Waves 2. Rayleigh Waves

Love (L) Waves Rayleigh Waves The fastest surface waves and moves the ground from side-to-side Moves the ground up and down, and side-to-side in the same direction that the wave is moving – kind of circular motion. Most of the shaking felt from an earthquake is due to the Rayleigh wave, which can be much larger than the other waves. Rayleigh Waves

Some Facts About Seismic Waves!!! 105 There’s an area on Earth, between ____ and ____ degrees from the ______, where no waves are detected – this area is known as the ______________ ___________ waves are not transmitted through ______ ________ waves are ________ and _________ but not stopped by the _______ outer core 140 focus Shadow Zone Secondary liquid Primary slowed deflected liquid www.saddleback.cc.ca.us/faculty/jrepka/notes/solidwaves.html

epicenter Epicenter epicenter Seismograph Stations (locating the epicenter) Need __ stations to locate the ________ ________ is located at the intersection Radius = distance to ________ epicenter 3 Epicenter epicenter

Need 3 Stations to Locate Epicenter!!!

Epicenter is located at the intersection!!!

radius = distance to the epicenter

Using Seismic Waves to Map Earth’s Interior

inner outer mantle crust ______ core – iron & nickel (solid) _____ core – iron & nickel (liquid) _______ – largest layer made up of silicon, oxygen, magnesium, and iron ______ –separated by Moho Discontinuity ***Seismic waves speed up and slow down due to density*** inner outer mantle crust

__________ - are used to measure P-waves, S-waves, & surface waves Seismographs

Let's Review!!! Stress elastic seismic primary secondary surface ______ builds up at the points where the surfaces of the fault touch. When the _______ limit of the rock is exceeded, it moves, producing ________ waves. There are three types of seismic waves including _________, ____________, and _________ waves. A ______________ measures seismic waves. _______ seismograph stations are needed to determine the location of an epicenter. The inner core, the outer core, the lower mantle, the upper mantle, and the crust make up _______. elastic seismic primary secondary surface seismograph Three Earth