Societe d’exploration Miniere du Haut Katanga (SEMHKAT)
Mwana has a 100% interest in 33 exploration licences covering about 4,721 km² in the Katanga copper belt region of southeastern DRC (figure 1).
Geology and history:
Kibolwe: The Kibolwe prospect, 160 kilometres north-west of Lubumbashi, is a significant secondary enriched sediment-hosted stratiform copper deposit hosted by Mines sub-group rocks. The dominant copper oxide mineral is malachite with minor amounts of cuprite and tenorite, which occur within weathered dolomitic shale. Copper sulphides of chalcopyrite have been altered to copper oxides in the oxidized zones of the deposit but remain feebly disseminated in fresh dolomitic shale. Figure 2 shows the current mapped geology of the Kibolwe surrounds area.
RC and core drilling programs carried out from 2004 to 2010 have outlined a near-surface, flat-lying mineralised zone up to 40 metres thick extending over a strike of 2,200 metres. A diamond core drilling program carried out in 2010 on the Eastern, Southern and Western extensions of Kibolwe (5 685.90 m) yielded encouraging results (Fig 3).
Indications are that all of the mineralized material is suitable for open-pit mining. A +400ppm Cu anomaly 1000 by 500m in areal extent to the east of Kibolwe Main has the potential to add to the total resources of the area. Diamond core drilling has been proposed to investigate the Kibolwe East Copper anomaly.
Lunsano: The Lunsano area (Fig 4) forms part of the Kitemena-Kitungulu-Kamungoti (‘KKK’) zones and lies on the far east of the KKK zones. The Lunsano area overlies both the Roan groups and lower Kundelungu rocks, and hosts a Cu-Pb-Zn anomaly. The copper data forms a coherent anomaly whereas Pb and Zn are more diffuse. The 2000 by 2000m copper anomaly has Cu values generally in the 80-150ppm range, and is underlain by the Roan group. A peak soil copper value of 1.38% was checked on ground and found to be located in-situ on laminated dolomitic shale. Detailed geological mapping and both regional and infill soil geochemical surveys are in progress. A 6000m RC drilling program has been planned.
Kitemena-Kitungulu-Kamungoti: The permit overlies Lower Kundelungu tillites, argillites and shales. Soil geochemical surveys conducted in 1998 and 2001 have outlined copper anomalies in the KKK area. The area has potential for Cu-Pb-Zn deposits as evidenced by the Cu-Pb-Zn anomalies picked up in the Kitungulu and Lunsano areas. Detailed geological mapping and regional soil surveys are under way. In addition to extension of regional geochemical surveys, infill geochemical surveys have also been planned as a follow-up to anomalies picked by regional soil surveys especially in Kitemena. A 2000m RC drilling campaign of has been planned to investigate the Cu-Pb-Zn anomaly at Kitungulu.
The +100ppm Cu Kamungoti Copper anomaly is 8000 by 500m in areal extent (Fig 5). The copper mineralization, where exposed in artisanal pits, is hosted within a shear zone at the contact of dolomitic shale and massive dolomite The shear zone hosts malachite mineralization associated with quartz veining and abundant iron and manganese oxides. Detailed mapping, regional soil geochemical surveys as well as a 2000m RC drilling program have been planned for the 2011/12 year.
Mwombe: The Mwombe area lies 13km to the east of Kibolwe Main and overlies units of mineralised Roan, Mines subgroup (Fig 6). The units form a series of anticlinal and synclinal folds verging towards the South. On a local scale breccias zones have been identified which are related to the regional Shinkolobwe SW trending thrust and fault structures which extend into the concession. The area is underlain by Grand Conglomerat, argillaceous shales and brecciated formations which comprise clasts of the Roan formations.
Exploration on the Mwombe North prospect has identified mineralised Mines sub-group strata outcropping over a 600-metre strike length. Assay results from trench and pit sampling programmes have yielded elevated nickel and cobalt values (up to 2% Ni and 0.38% Co over 1 metre) as well as gold, platinum and palladium (up to 1.1g/t Au, 0.1g/t Pt and 0.1g/t Pd). A 1,898m core drilling and 256m RC drilling program completed in 2008 intersected several encouraging mineralized units.
Mwombe South hosts a +150ppm copper anomaly which follows the trend of the cut-off between the Roan and the lower Kundelungu (Fig 6). Detailed mapping, pitting and trenching and RC drilling have been planned to investigate the Mwombe South anomaly.
Kawesitu North: Kawesitu North is situated 10km NNE of Kibolwe Main, and is underlain by formations related to the Roan Group and Lower Kundelungu.. According to Gecamines mapping the Kawesitu hosts five blocks (‘ecaile’) of Roan stratigraphy with Mines subgroup rocks (CMN, SD, RSF and D Strat). Gecamines mapped 10.2km strike length of Roan stratigraphy in and around the northern portion of the Kawesitu license area, of 5.5km prospective stratigraphy extends into the Kawesitu license. The blocks range from 0.5-1.2km in strike length. Numerous EW trending faults which may relate to mineralization events occur within the area. A geochemical sampling campaign was undertaken in 2007 on Kawesitu (N&S) on a 500X200m grid. This exercise yielded a 3000 by 500m anomaly of +200pppm Cu on Kawesitu North (Fig 6). The Swampo deposit is on the same structural trend. RC drilling has been proposed.
Mukema: The early-stage Mukema prospect has breccia-hosted copper-silver mineralisation developed within Kundelungu sediments. The breccia contains malachite, chalcopyrite and chalcocite along a 700-metre strike length. In places the mineralised breccia is 40 metres wide and coincides with a 4-kilometre long thrust fault zone highlighted from the aeromagnetic and radiometric data. Pit sampling of the breccia has yielded copper and silver peak values of up to 32.2% copper, 60g/t gold and 439 g/t silver.
Maniamuna Concessions (Kasai):Regional geochemical soil sampling programmes have been designed to follow up observed anomalies at Kafakumba, a sediment hosted copper target, and Lulua, a magmatic nickel copper-sulphide target in the south of the Maniamuna concession area. Geophysical surveys have been proposed for the 2011-12 financial year.
Current status and prospects:
Exploration work for the year 2011-12 will focus on Lunsano and the KKK zones. Detailed geological mapping, soil geochemical surveys and RC drilling have been planned. Mapping and soil geochemical surveys commenced towards end of June 2011.