The Tumentu Concession (PL 2/316) is located in the Western Region of Ghana, approximately 221km from Accra, 21km Southwest of the Tarkwa mine-site, and 22 km south of the Prestea mine-site. The concession is 8.74km2 in size, and is positioned immediately along strike between the Prestea Gold Mine and the Salman-Anwia project area being explored by Adamus Resources, where a total resource of 1.6 million ounces has recently been reported. Road access into the general area is South-West from Tarkwa, a distance of approximately 25km, or via Nkroful and Salman from the South for approximately 30km.
Artisanal mining, soil sampling, mapping and trench sampling, geological mapping and magnetic surveys have been undertaken and indicate anomalous gold levels within the concession.
On completion of a successful IPO and satisfaction of the terms of an option agreement, Noble will hold the existing rights over the joint venture agreement with Obotan Minerals Company Limited (Ghana) to earn a 78% interest in the Tumentu Concession by spending US$170,000 on the Concession by October 2008. Obotan would retain a 10% interest in the joint venture up to a decision to mine, which at that time will be negotiated within the parameters of the joint venture agreement. The Republic of Ghana retains a maximum of 10% interest in the Project from this time.
Geology
The Tumentu area straddles the contact zone between dominantly basaltic/andesitic volcanic flows, and metamorphosed volcanoclastic sediments. It is located 1,000m to the west of an interpreted major north-south trending transfer zone, marking the boundary of Tarkwaian lithologies.
Two broad lithological units can be identified within the Concession, based on the compilation of magnetic data and field mapping by previous explorers. Regionally, meta-volcanic and sedimentary rocks of Birimian age occur within the Concession. Locally, the western part of the Concession is characterised by high hills, and is predominantly composed of marine clastic sedimentary rocks. These rocks express a low magnetic response, and contrast sharply with the andesitic rocks in the eastern portion of the area. Along the northwest margin of the Concession, argillaceous sedimentary rocks, predominately phyllites and carbonaceous phyllites, are also mapped.
Fine-grained and clastic tuffaceous rocks occur often as float, and locally, the tuffs are sheared, micaceous and contain disseminated Fe-stained euhedral pseudomorphs of possibly arsenopyrite and/or pyrite. The stratigraphy generally strikes north-south, with variable dips between 35-88º towards either the east or west. The variable dip directions suggest that the rocks are folded.
Quartz occurs predominantly as float, with variably dipping quartz veins less than 2m wide, and veinlets (mm scale), identified often concordant to the foliation in the host rocks. Quartz-tourmaline veins and stockworks of tourmaline have been observed within andesite and Tarkwaian quartzite, respectively. Graphite, mica, and euhedral to anhedral disseminated Fe sulphides observed in the host rocks are interpreted to be hydrothermal alteration products, potentially related to structurally controlled gold mineralisation. Four old and active alluvial and elluvial gold workings have been located within the Tumentu licence. The workings consist of circular pits, and are believed to have been worked by both Indigenous People and Europeans.
Previous ground magnetic surveys have identified a number of elliptical-shaped high-magnetic bodies along the contact zone between the phyllitic and marine clastic rocks. It is interpreted that these features are intrusive rocks within a structurally complex zone, and may represent a pathway for fluid migration and potential mineralisation.