Table S1 Chugach Metamorphic Complex Boundinage Data from locations in D3 dextral shear zones. See Sisson and Pavlis (1993) and Scharman et al. (2011) for site locations. Averages for stretch, quadratic elongation, and shear strain are reported. Boudin dimensions were measured directly from outcrops at Wernicke Glacier and Western Copper River sites. Boudin dimensions were measured from photographs in Adobe Illustrator for the Transition Glacier and Tana Glacier sites. Site Wernicke Initial Length li (mm) 138 Final Length lf (mm) 342 Stretch S (lf/li) 2.47 197 77 345 Quadratic Elongation λ Shear Strain 6.1 1.3 2.55 6.5 1.4 146 2.36 5.6 1.2 298 138 2.15 4.7 1.0 895 138 6.48 42.1 5.1 290 152 1.90 3.6 0.7 585 366 1.59 2.6 0.3 5.90 2.19 2.69 7.3 1.6 4.80 0.74 6.47 41.9 5.0 7.15 3.49 2.04 4.2 0.9 0.249 0.159 1.56 2.4 0.2 Glacier Wernicke Glacier Wernicke Glacier Wernicke Glacier Wernicke Glacier Wernicke Glacier Wernicke Glacier Transition Glacier Transition Glacier Transition Glacier Tana Glacier Tana 0.141 0.302 2.13 4.5 0.9 0.077 0.119 1.54 2.4 0.2 0.159 0.367 2.30 5.3 1.2 0.079 0.158 1.99 4.0 0.8 0.059 0.177 2.99 9.0 1.9 0.074 0.162 2.19 4.8 1.0 0.027 0.106 3.85 14.9 2.7 Glacier Tana Glacier Tana Glacier Tana Glacier Tana Glacier Tana Glacier Tana Glacier