REVIEW
 
 

DEFINITIONS
 
 

READINGS

 Ch. 9

LECTURE
 
 

Definitions
 
 

Fault classification
 
 

Faults can be classified based on the true slip, the actual relative displacement (slip is a vector, magnitude, sense and direction).

 Faults can also be classified based on the apparent relative displacement. In fact, the offset observed in faults in outcrops, in map patterns and in structural profile is the 'separation' - sense and magnitude.

 One measure of apparent displacement is known as throw. You will use throw more often if you enter the oil industry. a throw is the separation without the sense, i.e. apparent the stratigraphic displacement but without saying .
 
 

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Were we to know the true total displacement, then we could use the following classification scheme based on the slip. Dip-slip faults are describer by reference to the actual relative movement of the hanging wall and footwall. The hanging wall is the block toward which the fault dips. The footwall is the block on the underside of the fault.

Insert figure 9.8

However, we do not always have a 3-dimensional view of faults. How can you find the slip from an apparent slip (separation)

 Normally you'll deal with faults in outcrop faces.

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 In this case the classification is a little different. Stratigraphic throw measures separation by stratigraphic thickness.
 
 

Determining Fault movement

Drag folds:, and reverse drag folds -antithetic faulting/synthetic faulting
 
 

Kinematic Analysis

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In rift systems, a convenient manner of describing the amount of extension: e= Lf-Lo/Lo

Andersonian Faulting