Summary:
The Syama Project is found on the northern margin of the Achaean-Proterozoic Leo Shield which forms the southern half of the West African Craton. The project area straddles the boundary between the Kadiana–Madinani terrane and the Kadiolo terrane. The Kadiana-Madinani terrane is dominated by greywackes and a narrow belt of interbedded basalt and argillite. The Kadiolo terrane comprises polymictic conglomerate and sandstone that were sourced from the Kadiana-Madinani terrane and deposited in a late- to syntectonic basin.
Prospects are centred on the NNE striking, west dipping, Syama-Bananso Fault Zone and Birimian volcano-sedimentary units of the Syama Formation. The major commodity being sought is gold.
The Tabakoroni deposit is hosted in upright tightly folded greenstone rocks of the Syama Formation, comprising interbedded basalt and sediment units, and an overlying complex sequence of deep marine and turbiditic sediments. The sequence overlying the basalts contains interbedded carbonaceous units (silts and shales) that are preferentially deformed, and which form the Tabakoroni Main Shear Zone (TMSZ) that lies along the approximate contact of the greenstone-sediment sequence. Gold mineralisation occurs within the TMSZ associated with quartz vein stockworks and stylolitic quartz reefs.
The Tabakoroni Porphyry Zone is located on a NNE trending splay of the NNW oriented Main Tabakoroni Shear Zone. Host rocks are comprised of interbedded greywacke and shale with small intrusions of quartz feldspar phyric dacite porphyry. Ductile shearing affects all units and is particularly focussed within the shale units. Mineralisation occurs as quartz-pyrite veins and sulphidic shears within shale units. Visible gold is commonly seen in vein quartz. The gold mineralisation at the ‘Porphyry Zone” is somewhat erratic with more coherent zones striking NNE and dipping shallowly and steeply west.
The Tabakoroni mineralisation is mostly steeply dipping, between 80 to 90°, with an average width of 4m to 15m. Some mineralisation is located parallel to, and adjacent to the main Tabakoroni mineralisation. These shallower dipping zones are located predominantly in a competent basalt zone, ranging in dip between 40° and 80°, with an average width of 2m to 10m.
Dimensions
The Porphyry Zone Mineral Resource area extends over a strike length of 700 metres (from 1,164,600 mN to 1,165,300 mN) and includes the 175 metre vertical interval from 345 mRL to 170 mRL. The overall plan width of the mineralised lodes varies between a few metres to 20 metres in thickness and is 600 metres wide (from 810,265 mE to 810,865 mE).
The Syama area extends for approximately 1,500 metres in strike and the west dipping gold mineralised zone is between 100-200 metres in horizontal width, narrowing at its southern and northern limits. The Mineral Resource is limited in depth by drilling, which extends from surface to a maximum depth of approximately 800 metres vertically.
The Syama North Mineral Resource area extends over a strike length of 6,000 metres (from 1,196,925mN to 1,202,800mN), and includes the 310m vertical interval from 455mRL to 145mRL The overall plan width of the mineralised lodes varies between 10 metres to 100 metres in horizontal thickness.
The mineral resource at Cashew comprises three individual domains they all dip at about 30 degrees to the west (local grid) from surface and extend 200 metres down dip. The three domains extend for approximately 350 metres along strike and the gold mineralised zone width varies between 1.5 and 20 metres, with an average thickness of 7 metres.
Three domains have been identified at Paysans. The three domains all dip at about 30 degrees to the west (local grid) and extend for 300 metres down dip. The mineralised zone width varies between 1.5 and 10 metres with an average thickness of 3 metres. They strike north-south (local grid) for approximately 1,700 metres. The deposit has been divided into three areas by two faults which run east-west (local grid).
There are three mineralised domains at Tellem. The three domains are narrow sub vertical zone of stockwork veins modelled to be between a few metres to 1.5 metres in thickness. The strike length is approximately 4.3 kilometres and covers a vertal extent of 270 metres.