Take out your notebook • Look at the worksheet page you did after the test. • Check your answers with those on the next slide!!
Forces in the Earth’s crust answers Reverse fault Compression Hanging wall moves up Normal fault Tension Hanging wall moves down Strike-slip fault Shearing Blocks move sideways in opposite directions Stress that moves rock in two opposite directions A large area of flat land elevated high above sea level
Write what is in yellow in a new page in your notebook. • Add it to your table of contents as “types of faults”
3 Types of Faults Normal fault Reverse fault Strike-slip fault
Normal faults • A normal fault occurs when one plate slides down another plate. • Tension is the force causing the plates to move apart
Reverse Faults • Reverse faults occur when one plate slides up another plate. • The angle is steep usually greater than 45 degrees. • Compression is the force that causing the plates to push together
Compression causes Anticlines and Synclines • Anticlines are folds in which each half of the fold dips away from the crest. Synclines are folds in which each half of the fold dips toward the trough of the fold. You can remember the difference by noting that anticlines form an “A” shape, and synclines form the bottom of an “S.”
Strike-slip Faults • Strike-slip faults occur when one plate slides either to the right or to the left of another plate. • Shearing is the force causing the plates to move past each other.
San Andreas Fault • It is more than 800 miles long and 10 miles deep! • It is an example of a strike-slip fault. • Locked sections remain still for about hundred years until there is enough force to move them. These sections result in massive earthquakes. • Sections that creep move slowly at a constant rate. They result in more subtle earthquakes.
The Future of CA The Pacific Plate is moving northwest of the North American Plate. Eventually California will be further north.
I live in Louisiana… • Why do I need to know this? • Earthquake game http://www.youtube.com/watch?v=XVrM8dSAtu4
http://www.youtube.com/watch?v=1MFzcl-kZHo&feature=related dog earthquake • http://www.youtube.com/watch?v=QPaHJ4rAEtM fault explained
Fault Block Mountains • http://videos.howstuffworks.com/hsw/6226-mountain-building-fault-block-mountains-video.htm • 3 types of faults – animation • http://www.geolsoc.org.uk/gsl/education/rockcycle/page3573.html • Epicenter Focus • http://science.howstuffworks.com/earthquake4.htm
SEISMOLOGY • THE STUDY OF EARTHQUAKES • THE SCIENCE DEALING WITH ALL EARTH MOVEMENTS AND WAVES
SEISMOLOGIST • THE SCIENTIST THAT STUDIES THE MOVEMENTS OF THE EARTH • A PERSON WHO STUDIES SEISMOLOGY • MUST KNOW FACTS ABOUT GEOLOGY, PHYSICS, AND CHEMISTRY
SEISMIC WAVES • CALLED EARTHQUAKE WAVES • THERE ARE THREE TYPES OF SEISMIC WAVES: • PRIMARY WAVES (P-WAVES) • SECONDARY WAVES (S-WAVES) • LONGITUDINAL SURFACE WAVES (L-WAVES)
SEISMOGRAPH • THE INSTRUMENT THAT MEASURES AND COLLECTS SEISMIC WAVES FOR EACH EARTHQUAKE. • IT SENDS THESE WAVE VIBRATIONS TO THE PRINTER MACHINE WHICH CREATES A GRAPH TO VIEW THE LOCATION OF THE SEISMIC WAVES • http://www.youtube.com/watch?v=VemVX6dQU_k seismograph
SEISMOGRAM • THE GRAPHED DRAWING OF THE EARTHQUAKE WAVES CAUGHT BY THE SEISMOGRAPH. SHOWS THE LOCATIONS OF MANY DIFFERENT SEISMIC WAVES SO THAT SEISMOLOGIST CAN DETERMINE WHERE, ON EARTH, THE EARTHQUAKE OCCURRED.