Ground Frequency Domain Electromagnetic (FDEM) and Magnetic surveys
were conducted in Southwest of the Ashanti belt in the Western Region of Ghana.
The aim was to delineate potential gold mineralisation zones that may
occur within the area. The magnetic data processing steps involved analytic
signal, first vertical derivative, upward continuation, CET grid analysis as well
as depth to basement model (Werner deconvolution). For the electromagnetic
survey using the two coil separations (100 m and 150 m) and the multi frequencies
(222 Hz, 888 Hz, 3555 Hz), the data in-phase component was
processed to produce EM component maps showing the potential mineralisation
zones. Lineament analysis using the rose diagram showed that the area is
dominated by N-S and NNW-SSE lineaments. The upward continuation and
depth to the magnetic source bodies indicated that the magnetic bodies in the
study area can be located at depth less than 200 m.
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