Recent advances in marine science and deep sea technology have highlighted the potential of mining gold and copper from the ocean floor.

The mineralization being investigated, known as Seafloor Massive Sulphide or SMS deposits, is associated with volcanic activity off the coast of Papua New Guinea (PNG). The mineral potential was confirmed last year when assays of 39 sulphide rich samples collected by hoop dredge over the Suzette field were calculated by Nautilus to average 12.2% copper, 15.5 g/t gold, 4.2% zinc and 256 g/t silver. If an economic gold and copper resource can be established, this project could become the first deep sea base metal mining operation in the world.

This week, the dynamically positioned ship the DP Hunter returned to Rabaul harbor PNG after conducting the world’s first successful commercial exploration for this class of mineral deposit. The program was conducted and managed by Placer Dome Oceania Limited, under the terms of a farm-in agreement with Nautilus. The 45 day cruise used state of the art technology to map and evaluate these deposits in water depths of 1,600 metres. Cornwall UK based drilling contractor SEACORE Ltd., completed 32 holes on the Suzette field where rich massive copper sulphide had been located by a major geophysics program in 2005.

A 200 horse power remote operated vehicle (ROV) capable of operating in water depths of up to 2,500 metres was equipped for this project with cameras (eyes), sonar (ears), manipulators (hands) to emulate many human tasks on the seafloor. (refer Media Photo Gallery www.nautilusminerals.com). The ROV aided in the identification of drill hole locations, acquired 100’s of hours of high resolution seafloor video footage as an aid to both biological and geological mapping of the sea floor and recovered large surface samples of the mineralized area. Marine biologists from James Cook University (Australia), University of Toronto, Canada and the college of William and Mary in Virginia USA, were on board the DP Hunter and documented over 3000 geological and biological observations during the first phase of ROV exploration, which included over 65 dives. Materials collected and observations recorded will form part of an environmental baseline study and the ongoing environmental evaluation of the Suzette field.

The ROV was fitted with a land based rock cutting tool to demonstrate the mineralized rock could be effectively cut and disaggregated by a machine at these depths. This program not only demonstrated the effectiveness of such a tool for a potential mining operation, but provided tonnes of material that was recovered as a bulk sample for future metallurgical testwork.

David Heydon, President and CEO of Nautilus, said: “This cruise represented the world’s first successful commercial evaluation of an SMS deposit and sets the scene for further evaluation of mineral resources on the sea floor in the foot steps of the offshore oil/gas industry.”

Scientists first became interested in seafloor massive sulphide deposits in the 1980’s, when they noticed similarities with the large volcanogenic mineral deposits on land, concluding that these deposits were likely formed on the ancient seafloor. Some of these land deposits, such as Kidd Creek in Canada and Mt. Isa and Broken Hill in Australia were of enormous economic importance, so a team led by Ray Binns from CSIRO, Australia’s national research organization, in collaboration with sea-floor geologist Steve Scott from The University of Toronto, began to study active seafloor vents. In 1991, they discovered large sulphide chimneys containing high-grade base and precious metals off the coast of PNG. Nautilus Minerals was formed to commercialize the decades of scientific knowledge in this field. Based on findings of the original scientific work, Nautilus acquired exploration licenses covering 15,000 sq kilometers of prospective seafloor in the Bismark and Solomon seas in the territorial waters of PNG. Nautilus was the first company in the world to be granted licences to explore for seafloor massive sulphide deposits. Whilst continuing to collaborate with the scientific community, Nautilus has also attracted leading engineering and offshore contractors and deep sea equipment suppliers to advise its board and management on the project.

Nautilus Minerals is the first company commercially exploring the ocean floor for gold and copper seafloor massive sulphide deposits and is positioned to become a world leader in underwater mineral exploration.
Source: Nautilusminerals.com