The current Simberi gold resources, reserves and mining operations are located in Mining Lease (ML) 136, which covers most of the eastern half of Simberi Island; the remainder of the island is covered by Exploration Licence (EL) 609, which also covers Tatau and Big Tabar Islands.
The gold deposits in ML 136 are located in a 4 x 2 km, north-south oriented area of a strong hydrothermal alteration and epithermal gold mineralization in a possible collapsed volcanic caldera geological setting, This altered, mineralized area represents only about 50% of the total hydrothermally altered area on Simberi – mainly in ML 136 but extending into EL 609. An excellent geological, geochemical and geophysical database exists to identify further oxide and sulphide gold drill targets.
Immediate targets are lateral and depth extensions of known resources in ML 136 not closed off by drilling to date. The potential to expand the total sulphide resource, particularly, is significant. Multiple other geochemical and geophysical anomalies in ML 136 and the immediately adjacent parts of EL 609 represent additional drill target areas.
Exploration of the western part of ML 136 and nearby parts of EL 609 has been hampered by partial cover of post-mineralization volcanic ash and by limited access, so that little definitive exploration has been carried out in recent years.
It is considered that there is potential throughout the 15 km2+ Simberi hydrothermal alteration area for high grade gold deposits in structurally competent andesitic volcanic units such as those underlying the volcaniclastic units that host most of the known mineralization.
There may also be potential for gold and copper mineralization in porphyry intrusions beneath the Simberi volcanic stratigraphy, particularly in the centre of the island, where there are a number of geophysical targets.