Structure of Rock - Rock Mechanics Based on an Anisotropic Jointed Rock Model - page 26

hemisphere subdivided in this way, analogous to that of Fig. 2.27, leads to the so-called
“equatorial equal-area net” illustrated in Fig. 2.28. The equatorial equal-area net enables
us to map a great circle of the lower reference hemisphere representing a discontinuity onto
a polar equal-area net. As an example, Fig. 2.29 shows the projection of the great circle
and the pole P of a discontinuity with a strike angle of

α = 115° and a dip angle of β = 60°.

Figure 2.28 Equatorial equal-area projection of lower reference hemisphere (Wittke 1990)