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Figure 1 – Fracture orientation across a prospect area and two crooked-line profiles (the dotted lines) used to evaluate fracture attributes. The solid lines show the position of the images created by crooked-line processing. Arrows labeled SH define the polarization of the SH particle-displacement vector on each seismic line. An older, pre-fold fracture set is oriented north-south; a younger and moredominant fold-related fracture set is oriented east-west. Line 1 follows the orientation of the dominant younger fractures. The SH displacement vector along Line 1 is the slow-S mode for the younger fractures. Line 2 follows the trend of any north-south fractures that may be present. The SH displacement vector along Line 2 will be the fast-S mode for the younger, dominant, pre-fold fractures. Modified from Alford and others (1989).