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Table 1 Sample description and results

From: Characterization of olivine fabrics and mylonite in the presence of fluid and implications for seismic anisotropy and shear localization

Sample 372 373 374 379 380 381
L M S L M S
Modal composition (%)a ol 10 33 18 61 97 64 35 57 50 30
opx 76 14 33 3 3 3 7 4 5 6
cpx 13 50 45 35 0 33 55 39 45 61
sp 1 3 4 1 0 0 3 0 0 3
LPO of olivineb E A + B B A + B (100) [010] B A + B E - A + B
M-indexc 0.27 0.08 0.17 0.1 0.06 0.04 0.06 0.04 0.04 0.1
Water content 3,620 to 3,500 cm-1d (ppm H/Si) 240 230 240 90 280 - 90 210 - 110
Water content 3,750 to 3,400 cm-1e (ppm H/Si) 400 430 370 110 600 - 320 400 - 320
Average grain sizef (μm) 2,090 1,470 1,620 1,270 53 9 1,670 50 10 1,240
Max. Vp anisotropy (%) 3.2 4.7 4.2 6.8 7.5 2.2 3.4 2.9 1.4 3.5
Max. Vs anisotropy (%) 2.37 2.94 2.43 3.77 5.20 1.33 1.94 1.86 0.92 3.19
Vp/Vs ratio 1.7 1.74 1.72 1.77 1.75 1.73 1.71 1.73 1.73 1.73
  1. Ol, olivine; sp, spinel. L, M, and S represent large-grained (wall rock), medium-grained, and small-grained areas, respectively. Medium- and small-grained areas belong to the mylonite zone. aGarnet grains were found as an accessory mineral in the small-grained area. bThe LPO of olivine classified in a previous experimental study (Jung et al. 2006). cThe M-index represents the fabric strength of olivine (Skemer et al. 2005). d,eThe water content of olivine was calculated using Paterson's calibration (Paterson 1982), using the IR bands between 3,620 to 3,500 cm-1 (d) and 3,750 to 3,400 cm-1 (e). Each result for water content is an average of 10 grains and excludes cracks and inclusions and uncertainty of water content is ±50 ppm H/Si. fGrain sizes for both the medium- and small-grained areas were determined by the linear intercept method (Gifkins 1970).