Publications des scientifiques de l'IRD

Perrouty S., Lindsay M. D., Jessell Mark, Ailleres L., Martin R., Bourassa Y. (2014). 3D modeling of the Ashanti Belt, southwest Ghana : evidence for a litho-stratigraphic control on gold occurrences within the Birimian Sefwi Group. Ore Geology Reviews, 63, p. 252-264. ISSN 0169-1368.

Titre du document
3D modeling of the Ashanti Belt, southwest Ghana : evidence for a litho-stratigraphic control on gold occurrences within the Birimian Sefwi Group
Année de publication
2014
Type de document
Article référencé dans le Web of Science WOS:000340975300017
Auteurs
Perrouty S., Lindsay M. D., Jessell Mark, Ailleres L., Martin R., Bourassa Y.
Source
Ore Geology Reviews, 2014, 63, p. 252-264 ISSN 0169-1368
A three-dimensional model of the gold-rich Paleoproterozoic Ashanti Greenstone Belt has been built with a "hybrid" geological modeling method using Geomodeller and Gocad, then inverted using VPmg software. The model helps to identify the main regional-scale controls leading to abundant gold mineralization in the southeast of the belt by highlighting the lithological distribution and geometry of geological structures. The three-dimensional geological model shows that 85% of gold occurrences in the Ashanti Greenstone Belt are proximal to a specific tholeiitic metabasaltic horizon "BV1". This result is noteworthy given that the relatively thin, 300 m thick, BV1 layer represents only 10%, by volume, of the modeled Sefwi Group stratigraphy. A map of distance between the topography and the BV1 layer is produced and identifies areas showing a high probability to host gold deposits in the southeast of the Ashanti Belt. Possible structural controls performed by the BV1 tholeiitic metabasaltic rocks on the location of gold occurrences are discussed, and we hypothesize that the BV1 layer acted as a mineralization trap or source of gold. Both hypotheses agree with examples from the literature and explain the observed distribution of the mineralized sites.
Plan de classement
Sciences fondamentales / Techniques d'analyse et de recherche [020] ; Géologie et formations superficielles [064]
Description Géographique
GHANA
Localisation
Fonds IRD [F B010062527]
Identifiant IRD
fdi:010062527
Contact