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Table T3. Abundance, mode, and chemical composition of the major rock types of Leg 176. (Continued on next 3 pages.)

Rock type Fraction of core Number of intervals Details






Mode






% Plagioclase Clinopyroxene Olivine
Troctolitic gabbro and troctolite 1.9 vol% 19 of troctolitic gabbro Average 64 10 26

4 of troctolite Maximum 80 15 40



Minimum 45 0 12



Grain size






mm Plagioclase Clinopyroxene Olivine



Avg max/1 SD 8/8 9/9 7/8



Avg min/1 SD 2/2 2/2 1/1



Chemical composition (10 analyses)





Wt% SiO2 TiO2 Al2O3



Average 49.58 0.24 18.13



Standard deviation 2.79 0.12 2.23



Maximum 52.65 0.42 22.05



Minimum 43.82 0.09 13.37










Mode






% Plagioclase Clinopyroxene Olivine
Olivine gabbro 69.9 vol% 255 Average 59 30 10



Maximum 75 60 35



Minimum 35 15 4



Grain size






mm Plagioclase Clinopyroxene Olivine



Avg max/1 SD 8/8 9/9 7/8



Avg min/1 SD 2/2 2/2 1/1



Chemical composition (62 analyses)





Wt% SiO2 TiO2 Al2O3



Average 51.94 0.44 16.40



Standard deviation 0.98 0.17 1.90



Maximum 54.46 1.17 21.23



Minimum 49.52 0.15 5.91



Mode






% Plagioclase Clinopyroxene Olivine
Gabbro 14.9 vol% 71 Average 61 34 3



Maximum 85 50 5



Minimum 48 10 0



Grain size






mm Plagioclase Clinopyroxene Olivine



Avg max/1 SD 16/11 24/19 4/3



Avg min/1 SD 4/3 3/2 1/0



Chemical composition (11 analyses)





Wt% SiO2 TiO2 Al2O3



Average 52.43 0.43 17.12



Standard deviation 0.63 0.07 1.09



Maximum 53.56 0.56 19.30



Minimum 51.43 0.35 14.96



Mode






% Plagioclase Clinopyroxene Olivine
Gabbronorite 5.6 vol% 12 Average 56 34 2
and ortho-
pyroxene-bearing gabbro


Maximum 65 45 6


Minimum 40 30 1




     



Grain size






mm Plagioclase Clinopyroxene Olivine



Avg max/1 SD 23/7 23/13 3/3



Avg min/1 SD 6/2 2/1 1/0



Chemical composition (two analyses)





Wt% SiO2 TiO2 Al2O3



Average 50.89 1.11 14.97



Standard deviation 1.22 0.62 0.78



Maximum 52.11 1.73 15.75



Minimum 49.67 0.5 14.19

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