Geological mapping and petrological studies were carried out within the placer gold (Au) mineralized zones in the Wonaka Schist Belt in order to establish detailed petrographic and structural features. Thin sections were produced for petrographic and microstructural studies and lineament analysis was coupled with field structural observations for interpretation. The study area comprises of quartz-mica-schist, phyllite, metasandstone, medium to coarse grained porphyritic granite, granitic gneiss, and diorite as the five major rock types with aplite, quartz and quartzo-feldspathic veins representing minor rock occurrences. The structural pattern is dominated by regional scale, NE striking foliation, and N striking brittle lineament. However, the dominant tectonic fabric within the metasediments and the granite gneiss are the steeply dipping, N, NW and NE-trending phyllitic cleavage, schistose foliations (S1) and gneissocity respectively, formed from first phase of deformation (D1). The emplacement of brittle tectonic features, undulose extinction observed in the quartz crystals, inter- and intra-granular microfractures are evidences of the late stage deformation that occur toward the end of the Pan African. Similarities with other mineralized belts in term of structures provide weight to the possibility of the NW-SE, N-S and NE-SW trending lineaments and specifically the NW-SE quartz and quartz ± feldspar ± hematite ± mica ± sulphide veins to host Au within the study area.
Key words: Wonaka schist belt; Structures; Placer gold mineralization; Petrology; Pan-African orogeny; Metasediments
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