Types of Faults and Stress Types: Strike Slip, Dip Slip, Normal, Reverse

1. LEQ: What are the categories and types of faults, and what type of stress produce each? Key Terms: displacement, strike slip fault, dip slip fault, right lateral fault, left lateral fault, normal fault, reverse fault, thrust fault Use the following link to help you with the definitions of your terms: USGS Earthquake Glossary

2. Your Model • In this power point you will be discovering the different kinds of faults through the discussion and the animations. • As you go through the power point, use your fault model to help you visualize the movement of the hanging and footwalls, and how the three types of stress cause movement along the fault.

3. Categories of Faults • A fault is a break in Earth’s crust where slabs of rock slip past each other. • There are two primary categories of faults that are determined by the direction of the displacement (movement) • Strike Slip Faults • Horizontal displacement • Dip Slip Faults • Vertical displacement

4. Strike Slip Faults • Strike slip fault: A category of faults where rock blocks on either side of the fault move past each other horizontally (sideways) with little to no up-or-down (vertical) motion. • Horizontal displacement. • Caused by the stress of shearing. • Animation

5. Types of Strike Slip Faults • Strike slip faults are classified by the horizontal direction (left or right) the rock blocks move with respect to each other. • For our study, we will concentrate on two primary types of strike slip faults • Right lateral fault • Left lateral fault • View the animations of Right Lateral and Left Lateral strike slip faults • After viewing the animations, use your fault model to demonstrate a right then a left lateral strike slip fault.

6. Dip Slip Faults • Dip slip fault: The category of faults where rock blocks on either side of the fault move past each other vertically (up or down) with little to no horizontal (sideways) motion. • Vertical displacement • Dip slip faults are caused by the stress forces of • tension • compression

7. Types of Dip Slip Faults • Dip slip faults are classified by the vertical direction (up or down) the rock blocks move with respect to each other. • For our study, we will concentrate on two primary types of dip slip faults • Normal faults • Reverse faults

8. Normal Faults • Normal fault: a type of dip slip fault where the hanging wall moves vertically downward with respect to the footwall. • Caused by the stress of tension. • Normal Fault Animation 1 • Normal Fault Animation 2 • After viewing the animations, use your fault model to demonstrate a normal dip slip fault.

9. Reverse Faults • Reverse fault: a type of dip slip fault where the hanging wall moves vertically upward with respect to the footwall. Note: A thrust fault is a kind of reverse fault. • Caused by compression. • Reverse Fault Animation 1 • Reverse Fault Animation 2 • When viewing animation 2, make sure you zoom in to get a better understanding of which block (side) is the hanging wall, and which block (side) is the footwall. • After viewing the animations, use your fault model to demonstrate a reverse dip slip fault.

10. Putting it all together. • Link to and use the animation to match the diagrams on the back of your worksheet.. • After matching the diagrams on the worksheet, close this power point, and turn in your activity sheet.