IJG  Vol.4 No.8 , October 2013
Petrochemical Characterization of Two Distinct Types of Dolerites from Bafoussam Area, West Cameroon
Abstract: Two petrochemical types of doleritic dykes have been distinguished in Bafoussam area: 1) the olivine-bearing dolerites which are the most representative are dark green, showing characteristics of alkaline basalts and, 2) the calcite-bearing dolerites are grayish green, showing characteristics of tholeiitic basalts. The studied dolerites are less differentiated (1 < FeOt/MgO < 2); they present the evolution of a subalkaline magma following a calc-alkaline series (alkaline dolerites) and the tholeiitic series (tholeitiic dolerite). The chondrite normalized multielement spider diagrams of all the dolerites show a pronounced depletion in Ba, Th, and enrichment in Rb. Their geotectonic context is inferred to be intraplate and the contrast between the two types is probably due to a diverse source: crustal source for calcite-bearing dolerites and mantle source for olivine-bearing dolerites.
Cite this paper: G. Nono, P. Wotchoko, S. Ganno, D. Njinchuki and J. Nzenti, "Petrochemical Characterization of Two Distinct Types of Dolerites from Bafoussam Area, West Cameroon," International Journal of Geosciences, Vol. 4 No. 8, 2013, pp. 1131-1144. doi: 10.4236/ijg.2013.48107.

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