Table 2.

Lithogeochemical data for representative Palaeoproterozoic granitic rocks of Man-Leo Shield. Data compiled from Lompo (1991), Ndiaye et al. (1997), Doumbia et al. (1998), John et al. (1999), Egal et al. (2002), Bumigeb (unpublished data). PAG, Palaeoproterozoic amphibole-bearing granitoids; averages data are from Burkina Faso (BF) (n=84), Ghana (n=2), Ivory Coast (n=4), Senegal (n=7) and Guinea (n=10). PBG, biotite±muscovite-bearing (without amphibole) granitoids; averages data are from Burkina Faso (BF) (n=103), Ivory Coast (n=2), Senegal (n=5) and Guinea (n=2). FeO=Fe2OT3 or FeOT.

Area Samples (n)PAGPBG
BFGHANAI. C.SENEGALGUINEEBFI. C.SENEGALGUINEE
84(+/−)2(+/−)4(+/−)7(+/−)10(+/−)103(+/−)2(+/−)5(+/−)2(+/−)
SiO2 (%)66.935.7068.440.3066.013.9363.713.6963.3072.603.5471.583.6271.801.1671.853.04
TiO2 (%)0.460.220.340.060.500.240.640.140.660.270.220.240.180.280.140.250.12
Al2O3 (%)14.701.4914.650.5415.321.7415.430.9815.8014.091.4115.211.0714.700.3514.451.20
Fe2O3 (%)4.342.043.530.133.391.595.001.295.412.001.161.661.151.630.662.200.77
MgO (%)2.081.551.810.401.520.902.720.912.200.550.500.830.910.400.210.550.21
CaO (%)3.851.903.620.043.571.173.541.154.201.740.901.440.911.040.531.300.57
Na2O (%)4.020.844.280.424.150.413.910.474.503.960.744.120.683.620.303.950.78
K2O (%)2.281.122.190.422.220.883.120.812.663.751.383.241.845.140.504.930.62
Rb (ppm)73.3239.0361.0015.5683.8043.11222.71105.9192.00140.4767.06151.25117.26262.2065.82190.5040.31
Ba (ppm)815.10442.13710.0062.23934.75268.02620.29108.421205.00854.40530.68522.3334.88601.80264.231213.00528.92
Sr (ppm)656.86391.86602.5012.02791.75216.20463.4382.92703.00390.39301.99315.17260.92185.20113.59290.00210.72
La 13927.8519.3118.5010.6128.7413.0537.5811.2946.7035.6925.9312.453.5640.4417.4665.159.69
Yb 1741.601.360.800.001.721.251.300.201.201.031.160.490.230.390.090.850.07