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Chapter 2 - 1 – Stress in the crust (part 1)
Right side
    stress -

1.  Stress in the crust-
    A.  A force that changes earth's surface

2. Types of Stress –

    A. Three types (fig. 2, page 45)

        1. Shearing B

                a.  slide past each other
        2. Tension C

                a.  pull apart from each other
        3. Compression D
            a.  press together

    B. Deformation

        1.  Earth's crust can bend, stretch, break, tilt, fold, and slide

        2.  Why?
          A.  Slow shift of plates's is the cause

Left side
figures to label & explain

Chapter 2 - 1 Faults (Part II )
Right side
    hanging wall -

1. Faults –
    A.Where do they occur?
        1.  Along plate boundaries
        2.  Plate motion compresses, pulls or shears the crust
        3.  Causes it to break.

2. Kinds of Faults –
    A. Strike-slip faults (fig. 3, pg. 46)
          1.  caused by shearing
            2.  transform boundary
    B. Normal faults (fig. 4, pg. 46)

            1.  caused by tension
            2.  divergent boundary
   C. Reverse faults (fig. 5, pg. 47) 

        1.  caused by compression
        2.  convergent boundary
        3.  blocks move opposite of normal fault
3.  Friction-
    A.  caused when two objects rub against each other 

    B..How does fiction play a role in earthquakes?
4.  Does the San Andreas fault affect us in Southern California?
5. What will happen millions of years from now to Southern California?
6. Mountain Building –
    A. Mountains formed by faulting – (fig. 7, pg. 48)
    B. Mountains formed by folding – (fig. 8, pg. 49)
 Left side
figures wksht.

Chapter 2 - 2  Measuring Earthquakes (part 1)
Right side
    seismic waves-

1. How many earthquakes are there everyday worldwide?
    A.  8000!
2. What two questions are always asked when an earthquake happens?

How big was it?
  Where was the epicenter?
3. Most earthquakes begin in the lithosphere.

    A.  within 100 Km of the surface

4. Seismic waves
    A.  3 catergories
        1.  P waves
        2.  S waves
        3.  surface waves  (L waves) 
            a.  produce severe ground movement

            b.  rolling motion

Left side
wksht.  to label

Chapter 2 - 2 Measuring Earthquakes (part II)
Right Side
Ch. 2-2 (part II) Measuring Earthquakes
   Mercalli scale-

1. Detecting Seismic waves
    A.  Seismograph
        1.  Measures and records vibrations
    B.  Fig. 13, pg. 56
2.  3 ways to measure earthquakes
    A. Mercalli scale
        1.  Used in early 20th century
        2.  Not a precise measurement
        3.  Fib. 14, pg 57
    B.  Richter scale
        1.  Rating of the size of seismic waves
        2.  Used for about 50 years then replaced
    C.  Moment Magnitude scale
        1.  Used today
        2.  But news reports give the moment
             magnitude number attached to the Richter
             scale (incorrect)
3. Locating the epicenter
    A.  Need 3 readings from 3 different seismographs

Fig. 17, pg. 59