General Geology

Geology

The TGME Project is situated within the Sabie-Pilgrims Rest Goldfield, approximately 300 km northeast of the Witwatersrand Basin, as shown in Figure 1. Gold mineralisation occurs within sedimentary host rocks of the Transvaal Supergroup. This metallogenic province extends for approximately 140 km in a north-north-easterly direction, over a maximum width of 30 km along the Great Escarpment of Southern Africa.

Epigenetic gold mineralisation in the Sabie-Pilgrims Rest Goldfield occurs as concordant and discordant (sub-vertical) veins (or reefs) in a variety of host rocks within the Transvaal Drakensberg Goldfield, and these veins have been linked to emplacement of the Bushveld Complex the largest igneous intrusion in the world (Figure 1, 2, 3). 

The mineralised zones occur as narrow quartz-carbonate veins (reefs) which generally conform to the shallow regional dip of the strata. Gold mineralisation is accompanied by various sulphides of iron, copper, arsenic and bismuth. The greatest part of mineralised zones which has historically been recovered from concordant, bedding parallel reefs was recovered from the Glynn’s and Theta Reefs. (Figure 2, 3)

Figure 1: Regional Geological Setting May 2019

Figure 2: Stratigraphic Succession of the Sabie-Pilgrims Rest Goldfields (Minxcon 2019)

 

Figure 3:Stratigraphy of Sabie Pilgrims Rest Goldfield

Principal gold mineralisation occurs

  • associated with vertical to subvertical structures hosted by 2.8 Ga Archean Granite and 2.2 Ga lower Proterozoic siliciclastics and dolomites (eg Rietfontein, Figure 2); 

  • within bedding parallel shear zones located within sedimentary host rocks of the 2.2 Ga Transvaal Supergroup (eg Beta, Figure 2); 

  • In association with regional thrusting on the Bevetts Unconformity which separates the Pretoria and Chuniespoort Groups 

  • Gold age ~ 1.98 Ga syn to late Bushveld Igneous Complex 


The regional structural geology is dominated by close space north east fault system (Figure 4). These faults have been the main fluid conduits for the gold mineralization. Often controlling the orientation of gold mineralising and deposition. This faults system remains under explored and is key to new discoveries.      

Figure 4 :Regional Geology Map with tenements and Historical Mine areas.