Geology of Leases
The Central Rand Group of sediments host all the mineralised reefs located on the West Rand Goldfield. Sedimentary deposition across the stable granite-gniess basement commenced around 3 billion years ago. In stratigraphic terms the Witwatersrand sequence is divided into two divisions, the lower dominantly marine, slate rich West Rand Group and the upper dominantly aluvial sandstone rich Central Rand Group. Combined, these units make up a sedimentary package up to 7km thick.
Sedimentary deposition ended approximately 2,700 million years ago when widespread faulting resulted in extensive lavas of the Ventersdorp supergroup covering the Witwatersrand Basin. Reef groups located on the West Rand in order of oldest to youngest are the Main, South, Johnstone, Livingstone, Bird, Kimberley, Elsburg and Ventersdorp Contact Reefs.
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The Bird Reef Group
The Bird Reef Group consists of up to five individual reefs; the Upper Monarch Zone 4 (Alpha), the Upper Monarch Zone 2 (Beta), the Monarch, the Footwall Monarch (middle) and the White Reefs. The Bird Reef Group is comprised of coarse quartz conglomerate horizons measuring up to 1.5m thick and containing numerous sulphides, gold and the uranium mineral uranite. Ore body geometry of the Bird Reef Group is classified as continuous through the West Rand Goldfield. The Bird Reef Group dips generally 30-40 degrees to the south, and strikes in a general east-west orientation.
The Kimberley Reef Group
The Kimberley Reef Group extends across the majority of the Company's Project Area. The Company believes the Kimberly Reef Group holds the potential for shallow mineralisation and possible underground mining. The Kimberley Reef Group consists of two dominant individual reef horizons; the Boulder (Lindum) and the Battery (Horsham) reefs. For many years these reefs provided the main source of gold on the West Rand Goldfield. The Kimberley Reef Group was known to have good continuity, with reef thicknesses varying from as little as half a metre to as much as 15 metres. The Kimberley Reef Group generally dips 30-40 degrees to the south and strikes in a general east- west orientation.
The Main and South Reef Groups
The gold bearing Main and South Reefs are the most extensively mined reefs on the Company's Project Area. These reef groups have a width ranging from a few centimetres up to a few metres and were mined to depths in excess of 2,000m in some sections of the Project Area. The Main and South Reef Groups were the first reefs in the Witwatersrand to be mined and were historically of a higher grade.
The Johnstone and Livingstone Reef Groups
The Johnstone and Livingstone Reef Groups are found in the western part of the Project Area (East Champ D'Or, Luipaardsvlei, West Rand Consolidated ("West Rand Cons") and West Wits). These reefs were mined for gold with thickness ranging from a few centimetres up to a few metres. The reef groups are separated by a distance from the younger Bird Reef Group and older South Reef Group of between 40m to 150m.
The Elsburg Reef Group
The Elsburg Reef Group is located on the DRD and Rand Lease, is stratigraphically younger than the Kimberley Reef Group and was not extensively explored or mined as it was regarded as uneconomic.
The Elsburg Reef Group is currently being successfully mined by other mining companies on the Witwatersrand for gold with minor uranium. The Company has identified this reef as a potential target, warranting further attention.
The Ventersdorp Contact Reef Group
Ventersdorp Contact Reef Group (VCR) is found on the unconformable boundary between the sediments of the Central Rand Group and the basalts of the Ventersdorp supergroup. The gold bearing VCR received minor exploration attention by the previous owners with moderate success. Original exploration drilling results are unavailable, however the Company believes this reef warrants investigation.