The Wassa deposit: A poly-deformed orogenic gold system in southwest Ghana – Implications for regional exploration

A review of the Birimian Supergroup- and Tarkwaian Group-hosted gold deposits of Ghana

“…at Prestea), to broad stockwork systems where the veins can be as thick as 20 m to 55 m. Generally the quartz vein-hosted gold mineralisation appears to be associated with the regional ductile to brittle D3 deformational event of northwest to southeast compression, as observed at Bepkong, Bogoso, Damang, Obuasi and Wassa. However, earlier quartz vein-hosted gold mineralisation associated with the D1 deformational event which caused folding of the Sefwi Group by north-south compression has been observed at Wassa (Griffis et al, 2002;Obuasi;Bibiani et al, 2002;Allibone et al, 2002b;Tunks et al, 2004;Amponsah et al, 2015a;Fougerouse et al, 2015;Perrouty et al, 2015).…”

“…1; Table 1) where this is an important mineralisation type include Bepkong, Bibiani, Bogosu, Damang, Konongo, Prestea, Wassa and the Yamfo district. This mineralisation type has been estimated to have a total gold inventory of approximately 1,100 t (~32 Moz) in Ghana (Milési et al, 1991;Mumin et al, 1994;Oberthür et al, 1997;Yao et al, 2001;Griffis et al, 2002;Allibone et al, 2002b;Pigois et al, 2003;Tunks et al, 2004;Amponsah et al, 2015aFougerouse et al, 2015Parra-Avila et al, 2015;Perrouty et al, 2015).…”

“…The first subtype of mesothermal quartz vein and quartz veinassociated sulphide type deposits, namely the quartz vein gold deposits, have multiple stage (e.g. three generations at Wassa; Perrouty et al, 2015), extensive, steeply dipping ( Fig. 5B) vein systems.…”

“…The majority of deposits show evidence for the quartzvein associated sulphide ores to have formed during the D2 extensional event and the quartz vein free gold ores to have formed during the Eburnean D3 compressional event (e.g. Allibone et al, 2002b;Tunks et al, 2004;Amponsah et al, 2015a;Fougerouse et al, 2015;Perrouty et al, 2015). However, examples of quartz vein free gold ores associated with the Eoeburnean D1 compressional event are also encountered .…”

Shear-related gold mineralization in Northwest Ghana: The Julie deposit

“…Junner, 1932;Milési et al, 1989;Klemd et al, 1996;Allibone et al, 2002;Feybesse et al, 2006;Perrouty et al, 2012Perrouty et al, , 2015White et al, 2015;Fougerouse et al, in press). Conversely, very little is known of the Birimian mineralization of NW Ghana (Fig.…”