Figure 4. Plot of Na2o + K2O - CaO vs. SiO2 (modified after 20)

From

Petrogenesis and Tectonic Setting of the Basement Rocks around Irruan Area, Bamenda Massif, SE Nigeria

Ominigbo O. E., Ukwang E. E., Okumoko J. P., Ukpai U. J.

Journal of Geosciences and Geomatics. 2020, 8(1), 35-44 doi:10.12691/jgg-8-1-5