Tritton copper deposit, Girilambone NSW. A geophysical discovery

Abstract

The Tritton massive sulphide copper deposit was discovered using systematic moving loop surface TEM surveys. The use of this technique was based on previous experience around the Girilambone copper mine. The deposit consists of an upper and lower lens, both of which are highly conducting. The lower lens was discovered through the use of downhole EM techniques. The upper lens lies at a depth in excess of 160 m below the surface and the lower lens is at a depth of greater than 400 m. Both these lenses have EM time constants of about 10 ms. Apart from having a minor associated magnetic anomaly the Tritton deposit has not been detected from the surface by any other geological, geochemical or geophysical technique. Approximately one kilometre north of Tritton is the uneconomic sulphide deposit, Budgerygar. This has similar geometry to the Tritton deposit but lies at the shallower depth of 60 m. The Budgerygar deposit is readily detectable by a variety of geochemical and geophysical techniques. The Tritton and Budgerygar deposits are an interesting test site for the development of new exploration technology, due to the similarity in their form but difference in depth and hence detectability. A number of geophysical techniques have been tested over the Tritton deposit since its discovery.