Regional geological setting
The geology underlying the Djimbala Project forms part of the Yanfollila Greenstone Belt. It consists of felsic to mafic volcanic rocks, sedimentary rocks deformed along fundamental deep seated faults, essential elements to form gold deposits in Mali. The weathering profile is reported to be between 80 and 100m deep which provides great potential for low cost open pit mining. The permit lies within a gold area where a number of projects are currently being developed. These projects include:
- Komana where the current gold resource declared by Gold Fields is 750,000 ounces of gold at a grade of 2.5g/t. This project is immediately to the northwest of the Djimbala Project.
- The Kordiera (2.52Moz Au resource) and Kalana (1.14 Moz Au resource) gold mines some 50 km south of Djimbala.
Prospects in the immediate vicinity of the permit include:
- Kabaya South, Gonka and Sanioumale West. Initial drilling by Gold Fields discovered high grade gold mineralization in the oxide zone on these projects. Drill results on Saniomale West (north of Komana) include 15m @ 10.1 g/t from 13m and 26m @ 3.87g/t from 24m.
- Solana, where an 8km by 3km gold in soil anomaly was outlined. This structure continues into the Djimbala permit.
- Faliko and Fougan where Gold Fields reported "encouraging results
Map showing the outline of the Djimbala Permit, locality of the Komana East gold deposit, prospects in the immediate vicinity and preliminary exploration targets
Farabantourou and Segala Ouest
These permits are situated in the Kenieba inlier, which are well-known for hosting world-class gold mines. The Kéniéba Inlier, a north-northwest trending granite-greenstone belt occurs along the Mali-Senegal border. The Kéniéba Inlier is comprised of Birimian volcano-sedimentary formations regionally metamorphosed to greenschist facies and intruded by large granitoid-gneiss complexes. In the Kéniéba region most of the gold deposits are contained within secondary structures and splay faults associated with the Senegal-Mali Fault Zone (SMFZ), often where southeast to northwest sutures cross-cut the dominant structural fabric. The gold deposits are hosted by penetrative shears and not by a single structural feature. This implies that the whole region has great potential for the discovery of additional gold deposits (Hyde, 2001).
The Loula (11.5 Moz gold resource), Sadiola (9.2Moz gold resource) and Yatela (3.5Moz gold resource) are all hosted by metasediments and volcanic rocks of the Kenieba Inlier and are within or on splays of the Senegal - Mali fault zone, the single most important structure for controlling gold mineralization in the Kenieba inlier. Also associated with this structure is Randgold’s new mine - Gounkoto - that has a resource of 5.76Moz at a gold grade of 5.28g/t.