Petrography and Geochemical Features of Dolerites Dykes from Fell (Adamawa Plateau, Cameroon-Central Africa)

Okomo AtoubaL.C.^1, , Fagny M.A.², Kada B.², Edima Yana R.W.³, Ngougoure M.S.² and Kamgang Kabeyene B.V¹

¹Higher Teacher Training College of Bertoua, University of Ngaoundéré, Po. Box. 652, Bertoua, Cameroon

²Department of Earth Sciences, Faculty of Sciences, University of Ngaoundéré, Po Box 454, Ngaoundéré Cameroon

³Centre for Geological and Mining Research, Po. Box. 333, Garoua, Cameroon

Cite this paper

Okomo AtoubaL.C., Fagny M.A., Kada B., Edima Yana R.W., Ngougoure M.S. and Kamgang Kabeyene B.V. Petrography and Geochemical Features of Dolerites Dykes from Fell (Adamawa Plateau, Cameroon-Central Africa). Journal of Geosciences and Geomatics. 2021; 9(2):74-82. doi: 10.12691/JGG-9-2-4

Abstract

Dolerite dykes from Fell locality in Southern Adamawa plateau in central Cameroon transect the granitoids of the basement along Pan African cracks of N70 and N135. They are 20 to 30 m in width and stretch on more than 100 m. Petrographical studies show intersertal doleritic texture defined by subhedral to euhedral k-feldspar, plagioclase, clinopyroxene and oxides. ICP-MS and ICP-AES geochemical analyses of Fell dolerites show that they are basalts of continental tholeiite affinity. Studied dolerites are the results of relatively high partial melting of E-MORB mantle source of spinel lherzolite composition. Lavas have evolved through fractional crystallization process coupled with continental crust contamination. Fell dolerites are considered as times markers of a geodynamic even combining limited stretching and tectonic phenomenon, probably the post Pan African relaxation setting.

Keywords

dolerite, continental tholeiite, pan african, Fell, Adamawa plateau, Cameroon

Copyright

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