1. I. Basic Techniques in Structural Geology
Fundamental principles
Field measurements and mapping
Terminology on folds
Terminology on faults
Stereographic projections
Preparing maps and constructing cross-sections
Seismic Imaging

2. Fault terminology To characterize fault geometry
Hanging wall
Footwall
High angle (dip>50)/ Low angle(dip<30)
To characterize fault slip
Net slip:
Strike slip
Dip slip:
Throw
Heave
so:,
Hanging wall
Footwall
(Net slip)^2 = (Strike slip)^2 + (dip slip)^2
(Dip slip)^2 = (heave)^2 + (Throw)^2
(Net slip)^2 = (Strike slip)^2 + (heave)^2 + (throw)^2

3. Fault terminology Normal fault
Thrust (low angle) or Reverse fault (high angle)
Right lateral
Strike slip Faults
Left lateral

4. Example

5. A real example illustrating the difference between apparent separations and true slip

6. Fault terminology
Normal fault
Thrust fault
Strike slip Faults

7. Fault terminology
To estimate slip on a fault one needs piercing points (i.e., the intersection of material line with the hanging wall and the footwall). The slip vector is determined from the strike-slip and dip-slip offsets of the piercing points.
In case of the offset of a planar surface (a bed or a dike for example) it is not possible to estimate slip, except if the rake in kown. In that case what is measurable is a separation vector. You need to define along which direction the separation is measured (strike, dip, vertical)
EX: If slip is not horizontal (meaning that the topography created by the dipslip component has been eroded) the strike-separation shown here is not the component of slip parallel to strike

8. Do not confuse separation and fault slip!

16. How to represent in map projection a plane and a line simultaneously (for example a slip vector on a fault plane, or a streching lineation on a foliation plane)?
How to estimate the intersection of planes (for example bedding planes to estimate the axis of a fold)?

17. Fossen’s online modules: http://folk. uib. no/nglhe/StructuralGeoBook
Visible Geology: