Petrology of Mafic Dykes from the Njimom Area (West-Cameroon): A Contribution to the Characterization of Late Paleozoic and Mesozoic Magmatism in the Southern Continental Part of the Cameroon Volcanic Line
Abstract
:1. Introduction
2. Geological Setting
3. Field Occurrence and Petrography
4. Analytical Methods
5. Results
5.1. Mineral Chemistry
5.1.1. Pyroxenes
5.1.2. Feldspars
5.1.3. Oxides
5.2. Whole-Rock Geochemistry
6. Discussion
6.1. Crustal Contamination
6.2. Petrogenesis
6.3. Geodynamic Implications
7. Conclusions
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Sample | NK0 | NK0 | NK0 | NK0 | NK0 | NK0 | NK0 | NK0 | NK0 | NK0 | NK0 | NK2C | NK2C |
Group | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites |
Description | gm | gm | gm | gm | gm | gm | gm | gm | gm | gm | gm | gm | gm |
SiO2 | 47.73 | 49.33 | 50.73 | 47.07 | 50.54 | 50.65 | 50.37 | 47.66 | 49.95 | 48.97 | 47.76 | 46.70 | 46.10 |
TiO2 | 2.35 | 1.13 | 1.10 | 3.29 | 0.17 | 0.05 | 1.25 | 1.59 | 0.93 | 1.22 | 1.58 | 2.54 | 2.77 |
Al2O3 | 6.35 | 2.48 | 2.41 | 6.79 | 1.33 | 1.38 | 2.48 | 4.63 | 1.79 | 4.08 | 5.20 | 5.84 | 5.84 |
FeO | 10.75 | 10.29 | 10.00 | 10.32 | 18.63 | 17.37 | 9.90 | 12.09 | 12.75 | 12.40 | 10.16 | 9.44 | 9.23 |
MnO | - | 0.73 | 0.23 | 0.08 | 0.89 | 0.80 | 0.32 | 0.46 | 1.13 | 0.90 | 0.54 | 0.36 | - |
MgO | 11.77 | 12.54 | 12.64 | 11.77 | 7.80 | 7.92 | 12.73 | 11.35 | 11.75 | 10.08 | 11.80 | 12.94 | 12.76 |
CaO | 21.75 | 21.20 | 21.73 | 21.33 | 21.26 | 21.91 | 21.02 | 21.04 | 21.31 | 20.91 | 20.93 | 20.40 | 20.21 |
Na2O | 0.50 | 0.15 | 0.51 | 0.59 | 0.92 | 1.01 | 0.40 | 0.82 | 0.40 | 0.49 | 0.52 | 0.53 | 0.58 |
Cr2O3 | 0.15 | - | - | 0.13 | - | 0.25 | - | 0.10 | 0.06 | 0.13 | - | - | 0.12 |
V2O3 | 0.08 | - | 0.06 | 0.17 | 0.10 | 0.15 | 0.29 | - | - | 0.10 | 0.01 | 0.32 | - |
sum | 101.45 | 97.86 | 99.42 | 101.53 | 101.63 | 101.48 | 98.76 | 99.74 | 100.08 | 99.28 | 98.51 | 99.06 | 97.59 |
Mg# | 66 | 68 | 69 | 67 | 43 | 45 | 70 | 63 | 62 | 59 | 67 | 71 | 71 |
Si | 1.768 | 1.897 | 1.912 | 1.743 | 1.929 | 1.928 | 1.913 | 1.799 | 1.893 | 1.876 | 1.818 | 1.760 | 1.762 |
AlIV | 0.218 | 0.097 | 0.081 | 0.246 | 0.048 | 0.048 | 0.085 | 0.174 | 0.089 | 0.120 | 0.169 | 0.222 | 0.223 |
Ti | 0.066 | 0.033 | 0.031 | 0.092 | 0.005 | 0.001 | 0.036 | 0.045 | 0.027 | 0.035 | 0.045 | 0.072 | 0.080 |
AlVI | 0.059 | 0.016 | 0.026 | 0.051 | 0.011 | 0.014 | 0.026 | 0.032 | −0.009 | 0.064 | 0.065 | 0.037 | 0.040 |
Fe3+ | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 |
Fe2+ | 0.333 | 0.331 | 0.315 | 0.319 | 0.595 | 0.553 | 0.315 | 0.382 | 0.404 | 0.397 | 0.323 | 0.298 | 0.295 |
Mn | 0.000 | 0.024 | 0.007 | 0.003 | 0.029 | 0.026 | 0.010 | 0.015 | 0.036 | 0.029 | 0.018 | 0.012 | 0.000 |
Mg | 0.650 | 0.719 | 0.710 | 0.650 | 0.444 | 0.449 | 0.721 | 0.639 | 0.664 | 0.576 | 0.670 | 0.727 | 0.727 |
Ca | 0.863 | 0.873 | 0.878 | 0.846 | 0.869 | 0.894 | 0.855 | 0.851 | 0.865 | 0.859 | 0.854 | 0.824 | 0.827 |
Na | 0.036 | 0.011 | 0.037 | 0.042 | 0.068 | 0.074 | 0.030 | 0.060 | 0.030 | 0.036 | 0.039 | 0.038 | 0.043 |
Cr | 0.005 | 0.000 | 0.000 | 0.004 | 0.000 | 0.008 | 0.000 | 0.003 | 0.002 | 0.004 | 0.000 | 0.000 | 0.004 |
V | 0.002 | 0.000 | 0.002 | 0.005 | 0.003 | 0.005 | 0.009 | 0.000 | 0.000 | 0.003 | 0.000 | 0.010 | 0.000 |
sum | 4.000 | 4.000 | 4.000 | 4.000 | 4.000 | 4.000 | 4.000 | 4.000 | 4.000 | 4.000 | 4.000 | 4.000 | 4.000 |
Ca | 47 | 45 | 46 | 47 | 45 | 47 | 45 | 45 | 44 | 46 | 46 | 44 | 45 |
Fe * | 18 | 18 | 17 | 18 | 32 | 30 | 17 | 21 | 22 | 23 | 18 | 17 | 16 |
Mg | 35 | 37 | 37 | 36 | 23 | 23 | 38 | 34 | 34 | 31 | 36 | 39 | 39 |
gm = groundmass; Mg# = atomic 100 × Mg/(Mg + Fe). | |||||||||||||
Ca, Fe * (Fe + Mn) and Mg in mol%. | |||||||||||||
NK2C | NK2C | NK2C | NK2C | NK2C | NK2C | NK2C | NK2C | NK2C | NK2C | NK2C | NK2C | NK2C | NK2C |
dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites |
gm | gm | gm | gm | gm | gm | gm | gm | gm | gm | gm | gm | gm | gm |
48.73 | 46.93 | 47.44 | 45.20 | 47.94 | 46.95 | 49.02 | 47.19 | 48.31 | 48.52 | 47.50 | 49.69 | 49.67 | 49.15 |
1.73 | 1.93 | 2.17 | 3.64 | 2.74 | 2.35 | 1.82 | 2.28 | 1.87 | 2.55 | 1.72 | 0.87 | 0.68 | 1.98 |
3.79 | 4.89 | 3.96 | 6.55 | 5.32 | 5.06 | 3.87 | 4.97 | 4.00 | 4.76 | 4.43 | 2.16 | 1.97 | 4.34 |
11.03 | 11.48 | 10.27 | 9.23 | 8.54 | 10.92 | 11.77 | 11.06 | 10.10 | 10.09 | 10.71 | 10.78 | 11.29 | 11.44 |
0.42 | 0.12 | 0.04 | 0.23 | 0.19 | 0.41 | - | 0.17 | 0.47 | 0.07 | 0.44 | 0.25 | 0.17 | 0.26 |
11.87 | 11.88 | 12.47 | 12.27 | 12.81 | 11.81 | 12.12 | 11.43 | 12.20 | 12.24 | 11.79 | 13.84 | 13.28 | 12.47 |
20.67 | 19.82 | 20.61 | 20.11 | 20.32 | 20.32 | 20.17 | 19.36 | 19.79 | 20.41 | 20.12 | 19.85 | 19.63 | 20.77 |
0.52 | 0.59 | 0.59 | 0.58 | 0.63 | 0.50 | 0.45 | 0.55 | 0.55 | 0.31 | 0.49 | 0.46 | 0.29 | 0.33 |
0.18 | 0.58 | 0.08 | 0.52 | 0.43 | - | 0.21 | 0.09 | - | 0.15 | - | 0.02 | 0.32 | 0.14 |
0.22 | 0.03 | - | - | 0.09 | 0.39 | 0.33 | - | 0.11 | - | 0.49 | 0.42 | - | 0.02 |
99.15 | 98.25 | 97.62 | 98.32 | 99.00 | 98.71 | 99.78 | 97.11 | 97.41 | 99.11 | 97.70 | 98.32 | 97.32 | 100.89 |
66 | 65 | 68 | 70 | 73 | 66 | 65 | 65 | 68 | 68 | 66 | 70 | 68 | 66 |
1.852 | 1.798 | 1.821 | 1.723 | 1.808 | 1.792 | 1.853 | 1.831 | 1.861 | 1.842 | 1.830 | 1.889 | 1.915 | 1.835 |
0.139 | 0.186 | 0.163 | 0.264 | 0.188 | 0.195 | 0.141 | 0.166 | 0.135 | 0.162 | 0.160 | 0.095 | 0.076 | 0.157 |
0.049 | 0.056 | 0.062 | 0.104 | 0.078 | 0.067 | 0.052 | 0.067 | 0.054 | 0.073 | 0.050 | 0.025 | 0.020 | 0.056 |
0.031 | 0.035 | 0.016 | 0.030 | 0.048 | 0.033 | 0.032 | 0.061 | 0.047 | 0.051 | 0.041 | 0.001 | 0.013 | 0.034 |
0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 |
0.350 | 0.368 | 0.330 | 0.294 | 0.269 | 0.349 | 0.372 | 0.359 | 0.325 | 0.320 | 0.345 | 0.343 | 0.364 | 0.357 |
0.014 | 0.004 | 0.001 | 0.007 | 0.006 | 0.013 | 0.000 | 0.006 | 0.015 | 0.002 | 0.014 | 0.008 | 0.006 | 0.008 |
0.673 | 0.678 | 0.713 | 0.697 | 0.720 | 0.672 | 0.683 | 0.661 | 0.701 | 0.693 | 0.677 | 0.784 | 0.763 | 0.694 |
0.842 | 0.814 | 0.848 | 0.822 | 0.821 | 0.831 | 0.817 | 0.805 | 0.817 | 0.830 | 0.831 | 0.808 | 0.811 | 0.831 |
0.038 | 0.043 | 0.044 | 0.043 | 0.046 | 0.037 | 0.033 | 0.041 | 0.041 | 0.022 | 0.037 | 0.034 | 0.022 | 0.024 |
0.005 | 0.018 | 0.003 | 0.016 | 0.013 | 0.000 | 0.006 | 0.003 | 0.000 | 0.005 | 0.000 | 0.001 | 0.010 | 0.004 |
0.007 | 0.001 | 0.000 | 0.000 | 0.003 | 0.012 | 0.010 | 0.000 | 0.004 | 0.000 | 0.015 | 0.013 | 0.000 | 0.001 |
4.000 | 4.000 | 4.000 | 4.000 | 4.000 | 4.000 | 4.000 | 4.000 | 4.000 | 4.000 | 4.000 | 4.000 | 4.000 | 4.000 |
45 | 44 | 45 | 45 | 45 | 45 | 44 | 44 | 44 | 45 | 44 | 42 | 42 | 44 |
19 | 20 | 17 | 17 | 15 | 19 | 20 | 20 | 18 | 17 | 19 | 18 | 19 | 19 |
36 | 36 | 38 | 38 | 40 | 36 | 36 | 36 | 38 | 38 | 36 | 40 | 39 | 37 |
NK2C | NK6 | NK6 | NK6 | NK6 | NK6 | NK6 | NK6 | NK6 | NK6 | NK6 | NK6 | NK6 | |
dyke in mylonites | dyke in granites | dyke in granites | dyke in granites | dyke in granites | dyke in granites | dyke in granites | dyke in granites | dyke in granites | dyke in granites | dyke in granites | dyke in granites | dyke in granites | |
gm | gm | gm | gm | gm | gm | gm | gm | gm | gm | gm | gm | gm | |
46.99 | 42.58 | 42.41 | 41.10 | 42.23 | 42.27 | 43.10 | 43.30 | 42.18 | 40.14 | 41.46 | 42.08 | 41.29 | |
2.02 | 6.10 | 5.56 | 6.58 | 5.28 | 5.49 | 5.42 | 6.12 | 6.36 | 6.67 | 7.24 | 5.39 | 6.76 | |
5.13 | 8.40 | 8.15 | 9.15 | 8.82 | 8.73 | 6.79 | 6.97 | 8.36 | 7.33 | 8.30 | 7.34 | 9.27 | |
9.23 | 12.02 | 11.54 | 10.73 | 10.76 | 10.81 | 14.00 | 13.74 | 13.08 | 11.67 | 11.23 | 11.28 | 12.93 | |
0.12 | 0.19 | 0.04 | - | - | 0.17 | 0.35 | - | 0.17 | 0.33 | 0.11 | 0.05 | - | |
12.31 | 8.72 | 8.80 | 8.42 | 9.56 | 10.20 | 7.82 | 7.92 | 8.46 | 8.34 | 9.04 | 8.52 | 8.52 | |
20.85 | 21.04 | 21.38 | 20.95 | 22.35 | 21.69 | 22.15 | 21.61 | 21.34 | 20.81 | 21.19 | 20.68 | 21.54 | |
0.57 | 0.61 | 0.93 | 0.50 | 0.53 | 0.61 | 0.58 | 0.43 | 0.87 | 0.49 | 0.88 | 0.57 | 0.67 | |
0.00 | - | - | - | - | 0.31 | 0.06 | 0.56 | - | 0.24 | 0.11 | 0.41 | 0.22 | |
0.49 | 0.08 | 0.28 | 0.61 | - | 0.30 | 0.19 | 0.29 | 0.11 | 0.03 | 0.08 | 0.13 | 0.22 | |
97.72 | 99.75 | 99.09 | 98.05 | 99.52 | 100.59 | 100.46 | 100.94 | 100.93 | 96.04 | 99.63 | 96.44 | 101.42 | |
70 | 56 | 58 | 58 | 61 | 63 | 50 | 51 | 54 | 56 | 59 | 57 | 54 | |
1.797 | 1.636 | 1.632 | 1.608 | 1.612 | 1.595 | 1.66 | 1.66 | 1.60 | 1.61 | 1.59 | 1.67 | 1.56 | |
0.189 | 0.357 | 0.350 | 0.393 | 0.369 | 0.382 | 0.32 | 0.33 | 0.38 | 0.38 | 0.39 | 0.32 | 0.42 | |
0.058 | 0.176 | 0.161 | 0.194 | 0.151 | 0.156 | 0.16 | 0.18 | 0.18 | 0.20 | 0.21 | 0.16 | 0.19 | |
0.043 | 0.023 | 0.019 | 0.029 | 0.028 | 0.006 | −0.02 | −0.02 | 0.00 | −0.03 | −0.02 | 0.02 | 0.00 | |
0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | |
0.295 | 0.386 | 0.371 | 0.351 | 0.344 | 0.341 | 0.45 | 0.44 | 0.42 | 0.39 | 0.36 | 0.37 | 0.41 | |
0.004 | 0.006 | 0.001 | 0.000 | 0.000 | 0.006 | 0.01 | 0.00 | 0.01 | 0.01 | 0.00 | 0.00 | 0.00 | |
0.702 | 0.499 | 0.505 | 0.491 | 0.544 | 0.574 | 0.45 | 0.45 | 0.48 | 0.50 | 0.52 | 0.50 | 0.48 | |
0.854 | 0.866 | 0.882 | 0.878 | 0.914 | 0.877 | 0.91 | 0.89 | 0.87 | 0.89 | 0.87 | 0.88 | 0.87 | |
0.043 | 0.046 | 0.069 | 0.038 | 0.039 | 0.045 | 0.04 | 0.03 | 0.06 | 0.04 | 0.07 | 0.04 | 0.05 | |
0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.009 | 0.00 | 0.02 | 0.00 | 0.01 | 0.00 | 0.01 | 0.01 | |
0.015 | 0.003 | 0.008 | 0.019 | 0.000 | 0.009 | 0.01 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 0.01 | |
4.000 | 4.000 | 4.000 | 4.000 | 4.000 | 4.000 | 4.00 | 4.00 | 4.00 | 4.00 | 4.00 | 4.00 | 4.00 | |
46 | 49 | 50 | 51 | 51 | 49 | 50 | 50 | 49 | 50 | 50 | 50 | 50 | |
16 | 22 | 21 | 20 | 19 | 19 | 25 | 25 | 24 | 22 | 21 | 21 | 23 | |
38 | 28 | 29 | 29 | 30 | 32 | 25 | 25 | 27 | 28 | 30 | 29 | 27 |
Sample | NK2A | NK2A | NK2A | NK2A | NK2A | NK2A | NK2A | NK2A | NK2A | NK2A | NK2A |
Group | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites |
Mineral Name | pl | pl | pl | pl | pl | pl | pl | pl | pl | pl | pl |
Description | gm | gm | gm | gm | gm | gm | gm | gm | gm | gm | gm |
SiO2 | 53.45 | 52.66 | 53.71 | 51.39 | 53.49 | 53.99 | 52.37 | 54.22 | 53.26 | 52.94 | 56.05 |
Al2O3 | 29.29 | 27.93 | 30.20 | 30.49 | 29.59 | 30.11 | 28.59 | 29.53 | 29.17 | 27.69 | 27.71 |
FeO | 0.75 | 0.62 | 0.45 | 0.05 | 0.79 | 0.55 | 0.31 | 0.24 | 0.80 | 0.89 | 0.47 |
CaO | 11.45 | 11.49 | 11.93 | 12.42 | 12.06 | 12.02 | 11.57 | 11.55 | 11.59 | 11.26 | 9.67 |
Na2O | 4.59 | 4.09 | 4.11 | 3.98 | 4.46 | 4.32 | 4.24 | 4.48 | 4.52 | 4.11 | 5.21 |
K2O | 0.55 | 0.36 | 0.36 | 0.43 | 0.55 | 0.47 | 0.59 | 0.44 | 0.65 | 0.64 | 0.61 |
BaO | - | 0.05 | - | - | - | 0.46 | 0.21 | 0.22 | 0.09 | 0.17 | - |
sum | 100.1 | 97.2 | 100.8 | 98.8 | 100.9 | 101.9 | 97.9 | 100.7 | 100.1 | 97.7 | 99.7 |
An | 56 | 59 | 60 | 62 | 58 | 58 | 58 | 57 | 56 | 58 | 49 |
Ab | 41 | 38 | 38 | 36 | 39 | 38 | 38 | 40 | 40 | 38 | 48 |
Or | 3 | 2 | 2 | 3 | 3 | 4 | 4 | 3 | 4 | 4 | 4 |
Si | 9.675 | 9.858 | 9.686 | 9.434 | 9.611 | 9.642 | 9.718 | 9.774 | 9.652 | 9.873 | 10.158 |
Al | 6.250 | 6.166 | 6.420 | 6.600 | 6.268 | 6.338 | 6.254 | 6.276 | 6.231 | 6.088 | 5.921 |
Fe | 0.114 | 0.097 | 0.069 | 0.007 | 0.119 | 0.083 | 0.048 | 0.036 | 0.121 | 0.140 | 0.071 |
Ca | 2.221 | 2.305 | 2.306 | 2.443 | 2.321 | 2.301 | 2.301 | 2.231 | 2.250 | 2.250 | 1.877 |
Na | 1.612 | 1.485 | 1.436 | 1.416 | 1.554 | 1.497 | 1.525 | 1.566 | 1.588 | 1.485 | 1.831 |
K | 0.128 | 0.085 | 0.083 | 0.100 | 0.127 | 0.107 | 0.139 | 0.101 | 0.151 | 0.151 | 0.142 |
Ba | 0.000 | 0.003 | 0.000 | 0.000 | 0.000 | 0.033 | 0.015 | 0.016 | 0.007 | 0.012 | 0.000 |
sum | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 |
pl = plagioclase; alk feld = alkali feldspar; gm = groundmass. An, Ab and Or in mol%. | |||||||||||
NK2C | NK2C | NK2C | NK2C | NK2C | NK2C | NK2C | NK2C | NK2C | NK2C | NK2C | NK2C |
dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites |
pl | pl | pl | pl | alk feld | pl | alk feld | pl | pl | alk feld | pl | alk feld |
gm | gm | gm | gm | gm | gm | gm | gm | gm | gm | gm | gm |
54.68 | 53.00 | 52.21 | 51.13 | 64.98 | 53.91 | 62.36 | 60.08 | 54.23 | 60.73 | 52.10 | 64.14 |
27.79 | 29.10 | 30.66 | 29.48 | 21.15 | 30.58 | 20.07 | 25.09 | 29.69 | 19.83 | 30.04 | 20.56 |
0.59 | 0.62 | 0.26 | 0.38 | 0.62 | 0.74 | 0.58 | 0.54 | 0.41 | 0.32 | 0.70 | 0.36 |
10.87 | 12.06 | 12.04 | 12.13 | 1.79 | 12.39 | 1.03 | 6.73 | 11.15 | 0.64 | 11.81 | 0.87 |
4.83 | 4.20 | 4.09 | 3.92 | 8.16 | 4.51 | 4.81 | 6.50 | 5.00 | 4.36 | 3.99 | 5.71 |
0.59 | 0.34 | 0.59 | 0.52 | 3.12 | 0.58 | 8.35 | 1.39 | 0.61 | 8.27 | 0.53 | 7.35 |
0.40 | - | 0.18 | 0.18 | - | 0.62 | 2.64 | 0.27 | - | 3.64 | - | 1.86 |
99.8 | 99.3 | 100.0 | 97.7 | 99.8 | 103.3 | 99.8 | 100.6 | 101.1 | 97.8 | 99.2 | 100.85 |
53 | 60 | 60 | 61 | 9 | 58 | 5 | 33 | 53 | 3 | 60 | 4 |
43 | 38 | 37 | 36 | 73 | 38 | 42 | 58 | 43 | 40 | 37 | 50 |
4 | 2 | 4 | 3 | 18 | 4 | 53 | 9 | 3 | 57 | 3 | 46 |
9.954 | 9.696 | 9.475 | 9.510 | 11.587 | 9.492 | 11.482 | 10.747 | 9.684 | 11.513 | 9.546 | 11.579 |
5.965 | 6.277 | 6.558 | 6.464 | 4.447 | 6.348 | 4.356 | 5.291 | 6.250 | 4.433 | 6.487 | 4.376 |
0.090 | 0.094 | 0.040 | 0.059 | 0.092 | 0.109 | 0.089 | 0.082 | 0.061 | 0.051 | 0.107 | 0.055 |
2.120 | 2.365 | 2.340 | 2.417 | 0.343 | 2.337 | 0.203 | 1.290 | 2.133 | 0.130 | 2.318 | 0.169 |
1.705 | 1.488 | 1.438 | 1.412 | 2.821 | 1.541 | 1.719 | 2.254 | 1.731 | 1.602 | 1.418 | 1.997 |
0.137 | 0.079 | 0.137 | 0.124 | 0.711 | 0.131 | 1.961 | 0.317 | 0.140 | 2.001 | 0.124 | 1.693 |
0.029 | 0.000 | 0.013 | 0.013 | 0.000 | 0.043 | 0.191 | 0.019 | 0.000 | 0.271 | 0.000 | 0.131 |
20.000 | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 |
NK2C | NK6 | NK6 | NK6 | NK6 | NK6 | NK6 | NK6 | NK6 | NK6 | NK6 | NK6 |
dyke in mylonites | dyke in granites | dyke in granites | dyke in granites | dyke in granites | dyke in granites | dyke in granites | dyke in granites | dyke in granites | dyke in granites | dyke in granites | dyke in granites |
pl | pl | alk feld | pl | pl | pl | pl | pl | pl | pl | pl | pl |
gm | gm | gm | gm | gm | gm | gm | gm | gm | gm | gm | gm |
54.00 | 53.16 | 65.78 | 53.38 | 53.50 | 54.04 | 52.12 | 53.73 | 56.82 | 62.83 | 53.42 | 53.92 |
27.45 | 29.44 | 19.04 | 29.30 | 29.42 | 28.14 | 29.97 | 28.73 | 28.92 | 21.58 | 29.31 | 29.16 |
0.64 | 0.99 | 0.41 | 0.47 | 0.87 | 0.93 | 1.24 | 0.44 | 0.53 | 0.45 | 1.37 | 0.75 |
9.22 | 12.57 | 0.57 | 11.60 | 12.13 | 10.16 | 12.54 | 11.26 | 10.98 | 3.20 | 12.14 | 11.38 |
5.29 | 4.27 | 5.49 | 4.37 | 4.19 | 4.80 | 3.99 | 4.77 | 5.05 | 8.24 | 4.29 | 4.31 |
0.71 | 0.11 | 8.76 | 0.41 | 0.23 | 0.30 | 0.40 | 0.49 | 0.50 | 2.39 | 0.34 | 0.41 |
0.16 | - | 0.45 | 0.05 | 0.14 | 0.10 | 0.49 | 0.53 | 0.06 | 0.89 | 0.40 | 0.18 |
97.46 | 100.54 | 100.50 | 99.57 | 100.47 | 98.48 | 100.76 | 99.96 | 102.86 | 99.58 | 101.27 | 100.12 |
47 | 62 | 3 | 58 | 61 | 53 | 61 | 54 | 53 | 15 | 59 | 58 |
49 | 38 | 47 | 40 | 38 | 45 | 35 | 42 | 44 | 70 | 38 | 40 |
5 | 1 | 50 | 3 | 2 | 2 | 3 | 4 | 3 | 15 | 3 | 3 |
10.000 | 9.613 | 11.833 | 9.727 | 9.694 | 9.951 | 9.443 | 9.759 | 10.004 | 11.275 | 9.623 | 9.797 |
5.993 | 6.277 | 4.039 | 6.296 | 6.284 | 6.110 | 6.403 | 6.152 | 6.004 | 4.566 | 6.224 | 6.246 |
0.099 | 0.149 | 0.062 | 0.072 | 0.131 | 0.142 | 0.188 | 0.066 | 0.078 | 0.067 | 0.207 | 0.113 |
1.829 | 2.436 | 0.109 | 2.264 | 2.356 | 2.005 | 2.435 | 2.191 | 2.072 | 0.615 | 2.343 | 2.215 |
1.899 | 1.498 | 1.916 | 1.543 | 1.472 | 1.713 | 1.403 | 1.680 | 1.725 | 2.866 | 1.498 | 1.519 |
0.168 | 0.026 | 2.010 | 0.095 | 0.052 | 0.071 | 0.094 | 0.114 | 0.113 | 0.548 | 0.078 | 0.096 |
0.011 | 0.000 | 0.032 | 0.003 | 0.010 | 0.007 | 0.035 | 0.038 | 0.004 | 0.063 | 0.028 | 0.013 |
20.000 | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 | 20.000 |
NK6 | NK6 | NK6 | NK6 | ||||||||
dyke in granites | dyke in granites | dyke in granites | dyke in granites | ||||||||
pl | alk feld | pl | alk feld | ||||||||
gm | gm | gm | gm | ||||||||
55.74 | 66.85 | 65.47 | 65.34 | ||||||||
29.34 | 20.08 | 21.65 | 20.01 | ||||||||
0.94 | 0.43 | 0.06 | 0.52 | ||||||||
11.95 | 1.49 | 2.37 | 1.78 | ||||||||
4.60 | 8.51 | 8.18 | 7.64 | ||||||||
0.40 | 3.47 | 2.44 | 3.83 | ||||||||
0.23 | 0.06 | 0.20 | 0.21 | ||||||||
103.21 | 100.90 | 100.36 | 99.33 | ||||||||
57 | 7 | 12 | 9 | ||||||||
40 | 73 | 73 | 68 | ||||||||
3 | 20 | 15 | 23 | ||||||||
9.826 | 11.786 | 11.627 | 11.768 | ||||||||
6.098 | 4.173 | 4.532 | 4.249 | ||||||||
0.139 | 0.063 | 0.009 | 0.078 | ||||||||
2.258 | 0.282 | 0.450 | 0.343 | ||||||||
1.572 | 2.911 | 2.815 | 2.667 | ||||||||
0.091 | 0.780 | 0.553 | 0.879 | ||||||||
0.016 | 0.004 | 0.014 | 0.015 | ||||||||
20.000 | 20.000 | 20.000 | 20.000 |
Sample | NK6 | NK6 | NK6 | NK2C | NK2C | NK2C | NK2C | NK6 | NK6 | NK6 |
Group | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in granites | dyke in granites | dyke in granites |
Mineral Name | cr-sp | cr-sp | cr-sp | mgt | mgt | mgt | mgt | mgt | mgt | mgt |
Description | incl | incl | incl | gm | gm | gm | gm | gm | gm | gm |
TiO2 | 3.16 | 12.40 | 3.36 | 24.63 | 21.14 | 25.36 | 19.77 | 20.37 | 20.37 | 20.59 |
Al2O3 | 24.30 | 9.90 | 25.06 | 2.06 | 0.16 | 0.00 | 4.23 | 3.83 | 3.06 | 4.41 |
FeO | 29.57 | 54.97 | 31.14 | 68.64 | 74.02 | 68.22 | 64.04 | 67.72 | 67.10 | 64.55 |
MnO | 0.40 | - | 0.67 | 0.51 | 0.48 | 0.88 | 0.86 | 1.90 | 1.71 | 1.51 |
MgO | 11.43 | 3.57 | 11.88 | 0.19 | - | - | 0.10 | - | 0.40 | 0.58 |
Cr2O3 | 27.18 | 18.30 | 26.58 | 0.20 | 0.71 | 0.55 | 7.21 | 1.66 | 2.89 | 2.97 |
V2O3 | 0.67 | 0.55 | 0.86 | 0.66 | 0.59 | 1.10 | 1.05 | 1.03 | 0.80 | 0.59 |
NiO | - | - | - | - | - | - | 0.55 | - | 0.56 | 0.99 |
sum | 96.70 | 99.70 | 99.54 | 96.90 | 97.10 | 96.10 | 97.80 | 96.50 | 96.88 | 96.21 |
Fe2O3 wt% | 10.65 | 17.14 | 12.08 | 17.28 | 26.48 | 16.82 | 16.77 | 21.51 | 21.47 | 18.73 |
FeO wt% | 19.98 | 39.55 | 20.27 | 53.09 | 50.19 | 53.09 | 48.95 | 48.37 | 47.77 | 47.70 |
sum | 97.8 | 101.4 | 100.8 | 98.6 | 99.8 | 97.8 | 99.5 | 98.7 | 99.0 | 98.1 |
Ti | 0.599 | 2.567 | 0.619 | 0.697 | 0.601 | 0.732 | 0.550 | 0.573 | 0.572 | 0.579 |
Al | 7.225 | 3.212 | 7.227 | 0.091 | 0.007 | 0.000 | 0.184 | 0.169 | 0.135 | 0.194 |
Fe3+ | 2.022 | 3.549 | 2.225 | 0.489 | 0.753 | 0.486 | 0.467 | 0.605 | 0.603 | 0.527 |
Fe2+ | 4.215 | 9.103 | 4.148 | 1.670 | 1.585 | 1.703 | 1.513 | 1.513 | 1.492 | 1.491 |
Mn | 0.085 | 0.000 | 0.138 | 0.016 | 0.015 | 0.029 | 0.027 | 0.060 | 0.054 | 0.048 |
Mg | 4.298 | 1.464 | 4.333 | 0.011 | 0.000 | 0.000 | 0.005 | 0.000 | 0.022 | 0.032 |
Cr | 5.420 | 3.983 | 5.142 | 0.006 | 0.021 | 0.017 | 0.211 | 0.049 | 0.085 | 0.088 |
V | 0.135 | 0.122 | 0.168 | 0.020 | 0.018 | 0.034 | 0.031 | 0.031 | 0.024 | 0.018 |
Ni | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.016 | 0.000 | 0.017 | 0.030 |
sum | 24.000 | 24.000 | 24.000 | 3.000 | 3.000 | 3.000 | 3.004 | 3.000 | 3.004 | 3.007 |
Ulv | - | - | - | 77 | 62 | 75 | 81 | 71 | 71 | 76 |
Ilm | - | - | - | - | - | - | - | - | - | - |
Mg# | 50 | 14 | 51 | - | - | - | - | - | - | - |
Cr# | 43 | 55 | 42 | - | - | - | - | - | - | - |
Chromiferous spinels structural formulas were calculated on the basis of 32 oxygens and 24 cations; magnetites were calculated on the basis of 4 oxygens and 3 cations; ilmenites were calculated on the basis of 3 oxygens and 2 cations; Cr# = atomic 100 × Cr/(Cr + Al), Mg# atomic 100 × Mg/(Mg + Fe2+). | ||||||||||
Ulv = ulvöspinel mol.%; Ilm = ilmenite mol.%; gm = groundmass; incl = inclusion; cr-sp = chromiferous spinel; mgt = magnetite; ilm = ilmenite. | ||||||||||
NK6 | NK6 | NK6 | NK6 | NK0 | NK0 | NK0 | NK2A | NK2A | NK2A | NK2A |
dyke in granites | dyke in granites | dyke in granites | dyke in granites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites |
mgt | mgt | mgt | mgt | ilm | ilm | ilm | ilm | ilm | ilm | ilm |
gm | gm | gm | gm | gm | gm | gm | gm | gm | gm | gm |
24.02 | 22.90 | 26.06 | 24.65 | 49.46 | 51.46 | 48.97 | 47.36 | 49.79 | 50.41 | 50.34 |
2.75 | 2.86 | 2.71 | 2.97 | 0.14 | 0.29 | 0.00 | 0.65 | 0.00 | 0.09 | 0.37 |
66.83 | 65.87 | 65.65 | 67.52 | 42.94 | 45.06 | 43.89 | 46.73 | 45.81 | 44.56 | 45.35 |
1.61 | 2.30 | 1.42 | 1.79 | 3.95 | 4.21 | 4.63 | 1.31 | 1.06 | 2.24 | 1.14 |
0.35 | - | - | - | 0.17 | - | - | - | 0.29 | - | 0.04 |
0.72 | 2.60 | 0.13 | 0.62 | 0.06 | - | - | 0.10 | 0.60 | 0.12 | - |
0.36 | 0.60 | 0.85 | - | 0.04 | 0.06 | 0.92 | 0.66 | 0.07 | 0.12 | 0.88 |
0.00 | - | 0.54 | - | - | - | - | 0.33 | 0.22 | 0.07 | 0.05 |
96.64 | 97.14 | 97.36 | 97.55 | 96.78 | 101.07 | 98.42 | 97.15 | 97.84 | 97.62 | 98.15 |
17.35 | 17.39 | 13.20 | 16.74 | 3.07 | 3.36 | 5.04 | 6.07 | 2.90 | 1.65 | 1.43 |
51.22 | 50.22 | 53.77 | 52.46 | 40.18 | 42.03 | 39.36 | 41.27 | 43.20 | 43.08 | 44.06 |
98.4 | 98.9 | 98.7 | 99.2 | 97.1 | 101.4 | 98.9 | 97.8 | 98.1 | 97.8 | 98.3 |
0.678 | 0.645 | 0.735 | 0.691 | 0.967 | 0.964 | 0.942 | 0.921 | 0.964 | 0.980 | 0.971 |
0.121 | 0.126 | 0.120 | 0.130 | 0.004 | 0.008 | 0.000 | 0.020 | 0.000 | 0.003 | 0.011 |
0.490 | 0.490 | 0.372 | 0.469 | 0.060 | 0.063 | 0.097 | 0.118 | 0.056 | 0.032 | 0.028 |
1.607 | 1.572 | 1.686 | 1.635 | 0.873 | 0.875 | 0.842 | 0.892 | 0.929 | 0.931 | 0.945 |
0.051 | 0.073 | 0.045 | 0.056 | 0.087 | 0.089 | 0.100 | 0.029 | 0.023 | 0.049 | 0.025 |
0.020 | 0.000 | 0.000 | 0.000 | 0.007 | 0.000 | 0.000 | 0.000 | 0.011 | 0.000 | 0.001 |
0.021 | 0.077 | 0.004 | 0.018 | 0.001 | 0.000 | 0.000 | 0.002 | 0.012 | 0.002 | 0.000 |
0.011 | 0.018 | 0.025 | 0.000 | 0.001 | 0.001 | 0.019 | 0.014 | 0.001 | 0.003 | 0.018 |
0.000 | 0.000 | 0.016 | 0.000 | 0.000 | 0.000 | 0.000 | 0.007 | 0.005 | 0.002 | 0.001 |
3.000 | 3.000 | 3.004 | 3.000 | 2.000 | 2.000 | 2.000 | 2.002 | 2.002 | 2.001 | 2.000 |
77 | 78 | 84 | 79 | - | - | - | - | - | - | - |
- | - | - | - | 97 | 97 | 95 | 94 | 97 | 98 | 99 |
- | - | - | - | - | - | - | - | - | - | - |
- | - | - | - | - | - | - | - | - | - | - |
NK2A | NK2A | NK2A | NK2C | NK2C | NK2C | NK2C | ||||
dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | ||||
ilm | ilm | ilm | ilm | ilm | ilm | ilm | ||||
gm | gm | gm | gm | gm | gm | gm | ||||
48.63 | 49.61 | 49.91 | 50.20 | 49.53 | 48.67 | 49.13 | ||||
0.20 | 0.00 | 0.20 | 0.14 | 0.10 | 0.04 | 0.15 | ||||
46.53 | 46.34 | 45.62 | 44.94 | 45.91 | 47.85 | 46.17 | ||||
1.43 | 1.78 | 0.87 | 1.27 | 0.87 | 0.83 | 1.27 | ||||
0.00 | 0.21 | 0.12 | 0.43 | 0.06 | 0.24 | - | ||||
0.00 | 0.24 | 0.21 | - | 0.10 | 0.39 | 0.13 | ||||
0.47 | 0.18 | - | 0.54 | 0.31 | - | 0.18 | ||||
0.03 | - | 0.28 | 0.81 | 0.18 | - | 0.51 | ||||
97.29 | 98.36 | 97.21 | 98.33 | 97.05 | 98.02 | 97.54 | ||||
4.71 | 4.33 | 2.02 | 2.05 | 2.60 | 5.94 | 3.63 | ||||
42.29 | 42.45 | 43.80 | 43.10 | 43.56 | 42.51 | 42.91 | ||||
97.8 | 98.8 | 97.4 | 98.5 | 97.3 | 98.6 | 97.9 | ||||
0.946 | 0.954 | 0.973 | 0.967 | 0.968 | 0.938 | 0.956 | ||||
0.006 | 0.000 | 0.006 | 0.004 | 0.003 | 0.001 | 0.005 | ||||
0.092 | 0.083 | 0.039 | 0.040 | 0.051 | 0.114 | 0.071 | ||||
0.915 | 0.908 | 0.949 | 0.923 | 0.946 | 0.911 | 0.928 | ||||
0.031 | 0.039 | 0.019 | 0.028 | 0.019 | 0.018 | 0.028 | ||||
0.000 | 0.008 | 0.005 | 0.017 | 0.002 | 0.009 | 0.000 | ||||
0.000 | 0.005 | 0.004 | 0.000 | 0.002 | 0.008 | 0.003 | ||||
0.010 | 0.004 | 0.000 | 0.011 | 0.006 | 0.000 | 0.004 | ||||
0.001 | 0.000 | 0.006 | 0.017 | 0.004 | 0.000 | 0.011 | ||||
2.000 | 2.000 | 2.002 | 2.006 | 2.001 | 2.000 | 2.004 | ||||
- | - | - | - | - | - | - | ||||
95 | 96 | 98 | 98 | 97 | 94 | 96 | ||||
- | - | - | - | - | - | - | ||||
- | - | - | - | - | - | - |
Sample | NK0 | NK1 | NK2A | NK2B | NK2C | NK2D | NK2E | NK2F | NK3 | NK4 |
Group | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites | dyke in mylonites |
Rock Type | haw | haw | alk bas | alk bas | alk bas | alk bas | alk bas | alk bas | haw | alk bas |
SiO2 | 48.23 | 51.19 | 46.32 | 47.87 | 47.07 | 46.08 | 47.66 | 46.79 | 51.32 | 49.54 |
TiO2 | 1.75 | 1.73 | 1.90 | 1.78 | 1.91 | 1.85 | 1.94 | 1.93 | 1.67 | 1.60 |
Al2O3 | 16.24 | 15.51 | 14.80 | 14.94 | 15.28 | 15.16 | 15.57 | 15.27 | 14.95 | 14.80 |
Fe2O3tot | 11.42 | 10.06 | 10.89 | 11.13 | 11.18 | 10.72 | 11.59 | 11.45 | 9.96 | 10.00 |
MnO | 0.17 | 0.14 | 0.14 | 0.15 | 0.17 | 0.15 | 0.14 | 0.17 | 0.15 | 0.15 |
MgO | 4.19 | 4.23 | 5.88 | 6.61 | 6.44 | 6.70 | 6.65 | 6.50 | 4.39 | 4.67 |
CaO | 6.16 | 6.15 | 7.98 | 7.33 | 7.37 | 7.36 | 6.59 | 7.57 | 6.43 | 6.79 |
Na2O | 3.70 | 2.49 | 2.71 | 3.03 | 3.29 | 3.35 | 3.08 | 3.12 | 3.11 | 2.65 |
K2O | 2.91 | 3.67 | 1.31 | 1.90 | 2.04 | 1.97 | 1.81 | 1.84 | 2.77 | 2.97 |
P2O5 | 0.84 | 0.60 | 0.56 | 0.48 | 0.59 | 0.52 | 0.59 | 0.61 | 0.59 | 0.51 |
LOI | 3.34 | 4.83 | 6.05 | 4.55 | 5.29 | 6.59 | 4.72 | 5.26 | 4.34 | 4.95 |
Total | 98.95 | 100.60 | 98.54 | 99.76 | 100.63 | 100.45 | 100.34 | 100.51 | 99.68 | 98.62 |
Be | 3 | 2 | 1 | 1 | 2 | 2 | 1 | 1 | 2 | 2 |
V | 96 | 118 | 149 | 144 | 151 | 148 | 153 | 156 | 119 | 122 |
Cr | 70 | 90 | 170 | 170 | 170 | 170 | 180 | 170 | 100 | 100 |
Co | 33 | 29 | 38 | 40 | 39 | 39 | 40 | 39 | 30 | 30 |
Ni | 30 | 40 | 90 | 110 | 100 | 110 | 100 | 100 | 70 | 50 |
Cu | 50 | 40 | 50 | 50 | 50 | 50 | 60 | 50 | 50 | 40 |
Zn | 100 | 100 | 100 | 90 | 100 | 90 | 100 | 90 | 110 | 100 |
Ga | 18 | 20 | 17 | 17 | 18 | 17 | 18 | 17 | 20 | 20 |
Rb | 75 | 122 | 41 | 54 | 53 | 48 | 47 | 54 | 107 | 94 |
Sr | 578 | 475 | 437 | 473 | 505 | 513 | 490 | 493 | 449 | 481 |
Y | 35 | 34 | 28 | 26 | 28 | 27 | 27 | 29 | 32 | 31 |
Zr | 295 | 278 | 211 | 216 | 221 | 209 | 222 | 216 | 286 | 252 |
Nb | 51 | 40 | 27 | 26 | 28 | 27 | 28 | 27 | 40 | 35 |
Sn | 3 | 3 | 2 | 2 | 1 | 2 | 2 | 2 | 3 | 3 |
Cs | < 0.5 | 3.6 | 1.4 | 1.2 | 1.2 | 1 | 0.9 | 1.2 | 2.2 | 4 |
Ba | 785 | 935 | 402 | 609 | 694 | 710 | 669 | 591 | 784 | 741 |
La | 52 | 50.5 | 31 | 30 | 32.1 | 30.3 | 30.5 | 30.2 | 48.4 | 51.8 |
Ce | 104 | 104 | 66.4 | 63.9 | 67.7 | 64.9 | 66 | 65.7 | 101 | 107 |
Pr | 12.1 | 12.6 | 8.39 | 7.83 | 8.51 | 8.07 | 8.25 | 8.17 | 11.9 | 12.7 |
Nd | 46.3 | 47.5 | 33.4 | 31.6 | 34.3 | 32 | 33.1 | 32.7 | 45.3 | 47.7 |
Sm | 8.7 | 9.4 | 7.2 | 6.7 | 7.4 | 6.7 | 6.9 | 7 | 9 | 9.7 |
Eu | 2.29 | 2.13 | 1.95 | 1.91 | 2.02 | 1.96 | 1.87 | 2.01 | 2.12 | 1.93 |
Gd | 7.90 | 8.10 | 6.80 | 6.60 | 6.60 | 6.20 | 6.30 | 6.80 | 7.70 | 8.00 |
Tb | 1.10 | 1.20 | 1.00 | 0.90 | 1.00 | 1.00 | 1.00 | 1.00 | 1.20 | 1.20 |
Dy | 6.80 | 7.00 | 6.10 | 4.90 | 6.10 | 5.60 | 5.70 | 6.00 | 6.60 | 7.20 |
Ho | 1.30 | 1.30 | 1.20 | 1.00 | 1.20 | 1.10 | 1.10 | 1.10 | 1.30 | 1.40 |
Er | 3.60 | 3.60 | 3.30 | 3.00 | 3.10 | 2.90 | 3.10 | 3.10 | 3.50 | 3.80 |
Tm | 0.50 | 0.51 | 0.44 | 0.38 | 0.46 | 0.41 | 0.42 | 0.42 | 0.47 | 0.54 |
Yb | 3.30 | 3.40 | 2.80 | 2.50 | 3.00 | 2.60 | 2.90 | 2.90 | 3.10 | 3.40 |
Lu | 0.51 | 0.52 | 0.39 | 0.39 | 0.44 | 0.39 | 0.42 | 0.43 | 0.51 | 0.53 |
Hf | 6.1 | 6.2 | 4.9 | 4.4 | 4.7 | 4.4 | 4.7 | 4.6 | 6.2 | 6.0 |
Ta | 3.5 | 2.8 | 1.8 | 1.7 | 1.9 | 1.8 | 1.8 | 1.7 | 2.7 | 2.8 |
Pb | 6 | 7 | < 5 | < 5 | < 5 | < 5 | < 5 | < 5 | 6 | 6 |
Th | 5 | 8 | 2.7 | 2.5 | 2.6 | 2.6 | 2.5 | 2.5 | 7.7 | 9.1 |
U | 1.4 | 1.6 | 0.6 | 0.6 | 0.7 | 0.6 | 0.6 | 0.6 | 1.5 | 1.7 |
Notes: Major oxides are in weight percent (wt.%) and trace elements in parts per million (ppm). LOI is loss in weight on ignition; alk bas, alkali basalt; haw, hawaiite. | ||||||||||
“Cert.” are the recommended values and “Meas.” the measured values on USGS and CANMET reference materials. | ||||||||||
NK5 | NK6 | NK7 | NK8 | W-2a Meas | W-2a Cert | SY-4 Meas | SY-4 Cert | JR-1 Meas | JR-1 Cert | |
dyke in mylonites | dyke in granites | dyke in granites | dyke in granites | |||||||
alk bas | alk bas | alk bas | alk bas | |||||||
51.43 | 42.18 | 41.98 | 43.73 | 52.48 | 52.40 | 49.71 | 49.90 | - | - | |
1.61 | 2.24 | 2.31 | 2.15 | 1.06 | 1.06 | 0.29 | 0.29 | - | - | |
15.02 | 12.85 | 13.44 | 12.20 | 15.55 | 15.40 | 20.35 | 20.69 | - | - | |
9.97 | 10.78 | 10.74 | 12.49 | 10.77 | 10.70 | 6.06 | 6.21 | - | - | |
0.14 | 0.20 | 0.16 | 0.19 | 0.17 | 0.16 | 0.11 | 0.11 | - | - | |
4.25 | 5.37 | 6.58 | 8.45 | 6.25 | 6.37 | 0.51 | 0.54 | - | - | |
5.89 | 13.94 | 11.91 | 8.96 | 11.03 | 10.90 | 8.14 | 8.05 | - | - | |
2.42 | 2.47 | 2.69 | 2.52 | 2.23 | 2.14 | 6.96 | 7.10 | - | - | |
2.55 | 0.93 | 1.06 | 0.98 | 0.62 | 0.63 | 1.66 | 1.66 | - | - | |
0.57 | 0.31 | 0.38 | 0.32 | 0.13 | 0.13 | 0.13 | 0.13 | - | - | |
4.49 | 9.21 | 9.16 | 8.24 | - | - | - | - | - | - | |
98.33 | 100.48 | 100.42 | 100.23 | 100.29 | 99.89 | 93.91 | 94.68 | - | - | |
2 | 2 | 2 | 1 | < 1 | 1.3 | 3 | 2.6 | - | - | |
113 | 208 | 215 | 205 | 266 | 262 | 9 | 8 | - | - | |
90 | 260 | 270 | 280 | 90 | 92 | - | - | - | - | |
29 | 51 | 54 | 53 | 43 | 43 | - | - | - | - | |
40 | 210 | 170 | 230 | 80 | 70 | - | - | < 20 | 1.67 | |
40 | 60 | 70 | 60 | 110 | 110 | - | - | < 10 | 2.68 | |
100 | 110 | 120 | 100 | 80 | 80 | - | - | 30 | 30.6 | |
20 | 18 | 19 | 17 | 18 | 17 | - | - | 15 | 16.1 | |
96 | 18 | 22 | 22 | 20 | 21 | - | - | 252 | 257 | |
468 | 683 | 608 | 528 | 200 | 190 | 1194 | 1191 | - | - | |
32 | 18 | 21 | 17 | 20 | 24 | 117 | 119 | - | - | |
249 | 130 | 128 | 123 | 95 | 94 | 538 | 517 | - | - | |
35 | 26 | 28 | 25 | - | - | - | - | 15 | 15.2 | |
3 | 1 | 2 | 1 | - | - | - | - | 3 | 2.86 | |
4 | 2.8 | 3.5 | 4.9 | - | - | - | - | 20.6 | 20.8 | |
725 | 268 | 263 | 256 | 173 | 182 | 348 | 340 | - | - | |
50.6 | 19.3 | 21.8 | 18.1 | 10.1 | 10 | - | - | 19 | 19.7 | |
105 | 38.1 | 43.7 | 36.7 | 24.3 | 23 | - | - | 44.9 | 47.2 | |
12.5 | 4.63 | 5.36 | 4.46 | - | - | - | - | 5.6 | 5.58 | |
47.1 | 18.4 | 21.9 | 18.2 | 13.2 | 13 | - | - | 21.9 | 23.3 | |
9.3 | 4.2 | 5.3 | 4.2 | 3.4 | 3.3 | - | - | 5.5 | 6.03 | |
1.89 | 1.58 | 1.79 | 1.51 | - | - | - | - | 0.27 | 0.3 | |
8.00 | 4.40 | 5.20 | 4.40 | - | - | - | - | 5.5 | 5.06 | |
1.20 | 0.70 | 0.80 | 0.70 | 0.6 | 0.63 | - | - | 1.1 | 1.01 | |
7.10 | 4.00 | 4.40 | 3.70 | - | - | - | - | 6 | 5.69 | |
1.40 | 0.70 | 0.80 | 0.70 | 0.8 | 0.76 | - | - | - | - | |
3.70 | 2.00 | 2.20 | 1.90 | - | - | - | - | - | - | |
0.51 | 0.25 | 0.30 | 0.27 | - | - | - | - | 0.62 | 0.67 | |
3.30 | 1.50 | 1.80 | 1.60 | 2.1 | 2.1 | - | - | 4.6 | 4.55 | |
0.50 | 0.23 | 0.25 | 0.23 | 0.31 | 0.33 | - | - | 0.7 | 0.71 | |
6.0 | 2.9 | 2.9 | 2.8 | - | - | - | - | 4.4 | 4.51 | |
2.8 | 1.6 | 1.7 | 1.5 | 0.5 | 0.5 | - | - | 2 | 1.86 | |
6 | <5 | <5 | <5 | - | - | - | - | 18 | 19.3 | |
9.1 | 2.1 | 2.2 | 2.1 | 2.4 | 2.4 | - | - | 25.4 | 26.7 | |
1.8 | 0.6 | 0.6 | 0.5 | 0.5 | 0.53 | - | - | 8.6 | 8.88 |
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Keutchafo, N.-A.K.; Simeni, N.A.W.; Nforba, B.K.; Noucoucouk, A.A.; Sonmo, J.D.; Tchaptchet, D.T.; Tchouankoue, J.P.; Cucciniello, C. Petrology of Mafic Dykes from the Njimom Area (West-Cameroon): A Contribution to the Characterization of Late Paleozoic and Mesozoic Magmatism in the Southern Continental Part of the Cameroon Volcanic Line. Geosciences 2022, 12, 12. https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences12010012
Keutchafo N-AK, Simeni NAW, Nforba BK, Noucoucouk AA, Sonmo JD, Tchaptchet DT, Tchouankoue JP, Cucciniello C. Petrology of Mafic Dykes from the Njimom Area (West-Cameroon): A Contribution to the Characterization of Late Paleozoic and Mesozoic Magmatism in the Southern Continental Part of the Cameroon Volcanic Line. Geosciences. 2022; 12(1):12. https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences12010012
Chicago/Turabian StyleKeutchafo, Noël-Aimée Kouamo, Nicole Armelle Wambo Simeni, Brillant Kandzi Nforba, Agathe Arrissa Noucoucouk, Josiane Demlabin Sonmo, Depesquidoux Tchato Tchaptchet, Jean Pierre Tchouankoue, and Ciro Cucciniello. 2022. "Petrology of Mafic Dykes from the Njimom Area (West-Cameroon): A Contribution to the Characterization of Late Paleozoic and Mesozoic Magmatism in the Southern Continental Part of the Cameroon Volcanic Line" Geosciences 12, no. 1: 12. https://0-doi-org.brum.beds.ac.uk/10.3390/geosciences12010012