Earthquakes+&+structure+review

Honors Earth Science Objectives // The test is tomorrow. Don’t forget to study your Ocean floor map so you will recognize the features in #1 of your objectives (not online). Question 20 is on the test but not online as well- study the 2 handouts given in class. // Purple has been corrected/checked by HESMASTER __ Structure of the Earth __ 2. What igneous rock makes up the ocean floor? What igneous rock makes up the majority of the continents? In the ocean, its extrusive igneous rock, basalt. The continents are made of Granite. -   Shelby. 3. Which is more dense, oceanic or continental crust? Oceanic Crust. -Shelby. 4. What are the 4 layers of Earth’s interior? the crust, mantle, outercore, and innercore. -chrissy 5. What is the Mohorovicic Discontinuity (the Moho) and how did it get its name? division between the crust & the mantle. name= scientist who discovered where crust ends. _christina 6. Which core is liquid? Why not the other core? the outer core. the material is stronger because of immense pressure -amanda 7. What 3 units compose a “plate”? What zone of the Earth’s mantle do plates “float” upon? oceanic crust, continental crust, lithosphere. plates "float" upon the asthenosphere -amanda __ Earthquakes  __ 8. What are the causes of earthquakes? tectonic plates colliding, volcanoes, explosions, avalanches, mudslides -amanda 9. How does a seismograph operate? a weight is suspended from a support thats attached to bedrock. when earthquake waves reach the instrument, the base stays stationary while earth and the support vibrate. -amanda 10. How many seismographs are needed to determine the location of an earthquake? At least three. -Shelby. 11. Compare and contrast each of these seismic waves: P, S, surface p waves- can travel through anything. s waves- cannot travel through outercore (liquid) surface waves- can travel through the surface. -chrissy 12. What’s the difference between the epicenter and the focus of an earthquake? Epicenter is the point on the earths surface directly above the focus. The Focus is the point within the earth from which energy is released. The size of the earthquake source cannot be accurately determined. -Shelby 13. How is an earthquake’s amplitude determined? you measure from middle to top of highest wave. _christina 14. How is the distance to an earthquake determined? the distance between p and s wave. -chrissy 15. Where and what is the shadow zone? Why does it happen? The shadow zone is the area of the earth that does not receive any waves. The shadow zone results from S waves being stopped entirely by the liquid core and P waves being bent by the liquid core. ~Lisha 16. What are seismic gaps and why are they of interest? places along faults where earthquakes do not often happen and because of that the chances of getting a really big earthquake is greater. -chrissy 17. Compare these two earthquake measuring scales: Richter and Mercalli The Richter scale measures the energy released by an earthquake. And the Mercalli scale measures the damage done by an earthquake. ~Lisha 18. Explain liquefaction: what happens and how it happens. Earthquakes happen& water level changes-  shoots up above ground &buildings sink&fall over. _christina 19. What are tsunamis? What are the 2 causes? it is a series of waves generated by an undersea disturbance. 2 causes are underwater earthquakes, landslides, and volcanic eruptions. -chrissy
 * // What kind of wave???  //**
 * // What type of water??  //**

Why do some areas shake more than others even though they receive the same amount of earthquake energy? Because some areas might have buildings built on mud or other soft material where there's other areas that have buildings that are built on hard pavement and solid rock. ~Lisha