Author(s)

Loudi Yap^1,2*, Robert Nouayou¹, Depesquidoux Tchaptchet Tchato³, Joseph Kamguia^1,2, Apollinaire Bouba^1,4

¹Department of Physics, Faculty of Sciences, University of Yaoundé 1, Yaoundé, Cameroon.
²Research Laboratory in Geodesy, National Institute of Cartography, Yaoundé, Cameroon.
³Department of Earth Sciences, Faculty of Sciences, University of Yaoundé 1, Yaoundé, Cameroon.
⁴Department of Physics, Advanced Teacher’s Training College, University of Maroua, Maroua, Cameroon.

The existence of mafic bodies at mid crustal level beneath the Pan-African Central Cameroon Shear Zone is still a matter of debate. To provide additional constrains on this issue, the crust of the west region of Cameroon has been investigated using gravity data. Analyses of these data show N40-50°E oriented iso-anomal contours in the Bafoussam area, interpreted as the N40-50°E branch of the Central Cameroon Shear Zone. In addition, spectral analysis and 2.5D gravity modeling reveal intrusions of mafic bodies at depth between 3.2 and 14.2 km under N40-50°E aligned volcanic centers, namely Mt Bambouto and Mt Mbapit. The above observations suggest a structurally controlled emplacement of the mafic bodies. In the light of the recent geophysical data, the interaction between the NE-ward channel flow operating at the bottom of the lithosphere or the asthenosphere upwelling and the Cameroon Shear Zone could better explain the magma upwelling in the upper crust. This result is the novelty of the present work.

West Region, Mafic Bodies, Central Cameroon Shear Zone, Gravity, 2.5D Modelling

Yap, L. , Nouayou, R. , Tchato, D. , Kamguia, J. and Bouba, A. (2018) Evidence for the Upwelling of Mafic Bodies into the Upper Crust beneath the N40-50°E Branch of the Pan-African Central Cameroon Shear Zone from Gravity Studies. Open Journal of Geology, 8, 278-297. doi: 10.4236/ojg.2018.83018.