Fig. 2. (a) Standard deviation and (b) correlation length of the logarithm of saturated hydraulic conductivity vs. scale of measurement in various fractured rock systems. Compiled from Andersson et al. (1989), Liedholm (1991), Armitage et al. (1996), Norris et al. (1997), Birkholzer et al. (1999), Finsterle (2000), and Niemi et al. (2000).