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 Camer...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.展开更多
This study focused on the interpretation of geophysical data collected from the Sissedougou prospect which is located at the southern end of the Korhogo-M’Benguebirimian trench. The geophysical surveys were carried o...This study focused on the interpretation of geophysical data collected from the Sissedougou prospect which is located at the southern end of the Korhogo-M’Benguebirimian trench. The geophysical surveys were carried out on two grids with two magnetometers and an induced polarisation unit composed of a transmitter and a receiver. The magnetic data allowed on one side the mapping of basic, intrusive and volcanic formations, weakly magnetic rocks produced by meta-sediments to be showed, and on the other hand to identify the continuity of the shear corridor observed southward and northward of the prospect. Induced polarisation data revealed the signature of sulphide and disseminated mineralization. The synthesis of the obtained results showed that deep NE-SW, NNE-SSW and N-S oriented fractures promoted the late rise of sulphide fluids. The setting of sulphide and gold mineralization in the southern part of the Boundiali trench is therefore controlled by ductile and brittle shearing.展开更多
文摘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.
文摘This study focused on the interpretation of geophysical data collected from the Sissedougou prospect which is located at the southern end of the Korhogo-M’Benguebirimian trench. The geophysical surveys were carried out on two grids with two magnetometers and an induced polarisation unit composed of a transmitter and a receiver. The magnetic data allowed on one side the mapping of basic, intrusive and volcanic formations, weakly magnetic rocks produced by meta-sediments to be showed, and on the other hand to identify the continuity of the shear corridor observed southward and northward of the prospect. Induced polarisation data revealed the signature of sulphide and disseminated mineralization. The synthesis of the obtained results showed that deep NE-SW, NNE-SSW and N-S oriented fractures promoted the late rise of sulphide fluids. The setting of sulphide and gold mineralization in the southern part of the Boundiali trench is therefore controlled by ductile and brittle shearing.