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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