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Two sets of high-angle to bedding compactive shear relationships, indicating coeval development (Tondi et
bands are present. They consist of compactive shear al., 2012). These two sets form one pair of conjugate
bands, which are either single bands or zones of bands strike-slip faults oriented N-S and NW-SE,
(Fig. 2 a and b). Faults including compactive shear respectively. The two sets of conjugate structures crop
bands with continuous slip surfaces and the associated out as: i) isolated, ii) interacting, and iii) linked features
cataclastic fault rock (Fig. 2 c), mark an advanced stage (Tondi et al., 2012).
of deformation within these carbonate grainstones. The
two sets of compactive shear bands have indicators Tondi et al. (2012) documented horizontal striations
showing strike-slip motion and mutually crosscutting along the slip surfaces of faults consequently, they
assumed that the slip along the faults is equal to the

Figure 2: Field examples of: a) single compactive shear band (CSB); b) zone of compactive shear bands
(ZB); c) fault with slip surfaces and fault rock. d) contoured plot of the poles (Schimidth lower hemisphere
projection) of the orientations of the three shear band structures. N-S structures show left-lateral
kinematics, NW-SE ones show right-lateral kinematics (after Tondi et al., 2012).

Stanford Rock Fracture Project Vol. 24, 2013 E-3