Table 3.

Electron microprobe analyses of minerals in sample 55-L

Mineralg-cg-cg-cg-rbi-gbi-gbipl-gplplksp
SiO237.1937.2237.6137.3634.4335.0334.0160.2362.8862.5466.01
TiO20.030.000.030.024.394.435.150.010.000.040.01
Al2O320.0120.0320.3120.4816.2316.0716.2924.8522.8323.2117.67
Cr2O30.030.010.020.040.060.040.050.020.000.020.00
FeO33.3533.4133.4435.9325.0023.9525.540.150.030.040.02
MnO1.191.051.181.050.010.030.060.000.000.010.00
MgO2.682.732.872.595.776.255.070.000.000.020.00
CaO5.055.004.432.360.000.010.007.545.265.090.14
Na2O0.040.040.040.050.140.170.186.797.908.181.75
K2O0.000.020.010.009.199.019.340.270.350.3113.75
Total99.5699.5099.9499.8895.2194.9895.7099.8699.2599.4699.34
O121212121111118888
Si3.003.003.023.022.712.742.682.692.802.783.04
Ti0.000.000.000.000.260.260.310.000.000.000.00
Al1.901.911.921.951.511.481.511.311.201.220.96
Cr0.000.000.000.000.000.000.000.000.000.000.00
Fe3+0.100.100.040.010.000.000.000.010.000.000.00
Fe2+2.152.162.202.421.651.571.680.000.000.000.00
Mn0.080.070.080.070.000.000.000.000.000.000.00
Mg0.320.330.340.310.680.730.600.000.000.000.00
Ca0.440.430.380.200.000.000.000.360.250.240.01
Na0.010.010.010.010.020.030.030.590.680.710.16
K0.000.000.000.000.920.900.940.020.020.020.81
XFe0.720.720.730.80XMg0.290.320.26XAn0.370.260.25XAn0.01
XMn0.030.020.030.02Ti0.260.260.31XAb0.610.720.73XAb0.16
XMg0.110.110.110.10XKsp0.020.020.02XKsp0.83
XCa0.150.140.130.07