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 |