Study Questions

 Guide #6 (F04)

 GEOL 125: Earth History

 Dr. Hammond

What types of faults exist? How can you tell if a fault is normal or reverse? What types of stresses create normal and reverse faults?

Draw cross sections illustrating the following: anticline, syncline, normal fault, reverse fault. Draw a map view of a right lateral fault. On what types of plate boundaries is each type of fault expected (relates to plate tectonics lectures)?

How can a fault be recognized in the field? Draw a picture of a normal fault, and indicate hanging wall, foot wall, strike, and dip. What is a fault scarp?

What types of seismic waves exist? Which travel fastest? Which are most damaging? How many seismic stations does it take to determine the location of an earthquake? Why do earthquakes only originate in the upper 670 km?

How do we use seismic waves to define the crust, mantle, core, and low velocity zone? How do we know that the outer core is liquid? Compare the density, composition, and seismic velocity of the crust, mantle, and core.

Draw a diagram showing the travel paths of body waves through the earth as they propagate away from an earthquake (see Fig. 10-2). Why are these paths curved? Identify the shadow zone and explain why it exists. Indicate where we receive only p-waves, and explain why s-waves are not observed everywhere that p-waves are observed.

How do we know the distribution of temperature in the interior of the earth? Why is the interior hot? What effect does increased temperature have on the response of earth materials to stress?

Terms to know

 anticline  syncline crust
plunging fold strike dip
  fault   compression  extension
  normal fault   reverse fault   lateral fault
  tectonics  stress   strain
  brittle   elastic   plastic
  seismometer   p-wave   s-wave
 body wave  surface wave seismic refraction
  seismic reflection  epicenter  focus
 outer core  inner core  low velocity zone
 Mohorovicic discontinuity Moho mantle