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The pole of the plane

Any plane can be represented by means of a line which is perpendicular to the plane. This projects a dot on the stereogram called the pole of the plane. It's useful in rotation or measuring the angle between two planes.

There are two methods to plot a pole, it can be calculated or simply drew basis on a plane parameters.

Firstly, the metod of drawing a pole, explained with an example: Plot the projection of the pole of the plane 082/28.
Mark on the overlay point to represent the dip direction 82. Rotate the net until the point joins the equator. Then measure the dip angle, but do it form the center of net in the oposite direction than the dip of the plane. Estabilish a dot, it's pole we required.

Notation of the pole can be calculated, to. Calculating the plunge of the pole is the same, despite the notation : plunge of pole = 90 - angle of dip.
Whereas calcualting of plung direction depends on notation:

• for 2-part version - direction of plunge of pole =dip direction + (or -) 180.

  Example: pole of the plane 237/24. plunge: 90 - 24 = 66.
  Plunge direction: 237 - 180 = 57. The pole of this plane is 66-057.

  Remember! The pole is a line, so notation is the same as for line.

• for 3-part version - plunge direction = strike of plane + (or -) 180.
  

An important preliminary to constructing a pole (and every projection) is to anticipate the outcome. Force yourself to visualize the projection before you start drawing.