Application of magnetic and electrical geophysical methods in delineating auriferous structures in the Sefwi belt of Ghana

Loading...
Thumbnail Image
Date
OCTOBER, 2016
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Gold is a very important economic commodity to the growth of Ghana‟s development. The prospecting and exploration stages of mining involve long periods of investment with a high risk of failure. Even before strenuous effort is put into the discovery of reserves, many exploration companies become cash-strapped to the extent of collapse and may find near mine development very challenging. For this reason prospecting for gold needs to be optimized and that calls to mind the attention of choosing the right techniques that will enhance the success of the exploration projects. Four indicative spatial features -shear (ductile) zones, favorable host rock units with fracture arrays, hydrothermal alterations and strongly deformed (brittle) or faults zone- were the driven force behind this research. Two geophysical methods namely ground magnetic and electrical tools were integrated with existing geological dataset to map out structures in the Sefwi belt of Southern Ghana. The magnetic data obtained were processed into grids with Geosoft. Data enhancement filters such as reduction to the pole, tilt-angle derivative, first and second vertical derivatives and continuation filters were further applied to Total Magnetic Intensity (TMI) grid to enhance magnetic anomalies. The induced polarization-chargeability data were measured in the time domain. The positive anomalies on the IP-chargeability map coincided with the shears margins alterations and contact zones. Two dipole–dipole sections were carried out in the study area and were inverted using the RES2DINV program. From the results obtained, an interpreted definitive geologic map of the study area consisting of the geology, structures and hydrothermally altered zones were produced with MapInfo (Discover). All recognizable features were mapped as major and inferred thrust fault, lineation and alteration. The result is a preliminary mineral potential map...
Description
A Thesis Submitted to the Department of Geological Engineering, Kwame Nkrumah University of Science and Technology in partial fulfilment of the requirements for the degree of Master of Science(Geophysical Engineering) College of Engineering,
Keywords
Citation