Undersea minerals - new prospecting in SI waters

Solomon Islands is part of the next great mining rush - taking place under the sea.

A Canadian-listed company called Nautilus Minerals (NMO) has acquired exploration and prospecting rights to an area of the SI EEZ roughly southwest of New Georgia. These areas form part of what the company calls its "Solwara" projects, spanning seafloor areas in the PNG, Tongan and SI EEZs. The Solwara project has a number of different fields (Solwara 1- 8) and aims to exploit seafloor sediments called SMS deposits, which are rich in gold, silver, copper and zinc.

The "Solwara" project areas (click to enlarge)

Seafloor massive sulphide (SMS) deposits are a class of minerals deposits at the centre of a new mining industry focusing on the seafloor. They are formed during a process called hydrothermal circulation, in which seawater enters deep cracks in the earth's crust below the seafloor. The water is superheated and returns to the ocean via undewater volcanic vents called black smokers. The water carries with it considerable deposits of minerals which are
then deposited on the ocean floor. These deposits are found anywhere from a few metres to more than a kilometer under the sea surface.

And they exist in SI EEZ waters.

According to Nautilus sources, they have been granted more than 10 thousand square kilometers of tenements by the SI govenrment. Whether these tenements have exploration, prospecting or mining rights attached is not immediately clear:

As of November 14, 2007 Nautilus had been granted 14 tenements covering 10,641 km2 in the Exclusive Economic Zone of the Solomon Islands, continuing the Company's tenement holding in the highly prospective Woodlark Basin to the east of PNG. The licences granted in the Solomon Islands are an extension of our highly prospective Woodlark Basin tenements to the east of PNG. All of the Solomon Island licences are 100% owned by Nautilus

The tenements stretch for a considerable distance south and southwest from the Western Province islands of Ranonnga, Rendova and New Georgia.

Given a national mining scene that is heating up all over the place and significant economic pressures forecast, this development is sure to attract the attention of a lot of people - economic planners and the Western provincial government especially. Also with, some of the tenements abutting the shoreline of Rendova, customary landowners may begin taking a new interest in reef and coastal rights.

Malaita diamond explorations

With the disappearance of SI forests, the search for alternative resources for exploitation is speeding up.

Most recent has been the focus on diamond exploration on Malaita. This week, Cabinet was briefed on the possibilities of microdiamond presence on Malaita by Prof. Ken Collerson of the University of Queensland.

According to Solomon Times Online, earlier this week he

"...told Government he was optimistic about the presence of diamond and other minerals because of his earlier finding about the presence of micro diamond in rocks obtained from Malaita."

Prof Collerson first raised this possibility in a 2000 Science article on the discovery of garnet minerals amongst surface rocks in the northern part of Malaita. While the geological significance of this discovery lay in the transport of very deep rocks (normally 400-670km under ground) to the surface very rapidly (ie in only 2-3 days), for Malaitans the significance was a potential mining industry.

Some 8 years later, the time for further exploration may have come. The current Minister for Mines and Energy, Edward Huniehu, has called for urgent aerial survey of the island.

In his statements to the media, Huniehu also quoted Collerson as indicating that:

...[he] believes Malaita has the geological potential to be a Greenfield exploration target for diamond, nickel, platinum group metal and gold.

Any such mineral discoveries on Malaita would help the government overcome two pressing development challenges:

• the need for export earnings as logs run out (currently projected for 2010)
  
• the need for large resource projects on Malaita to reduce interisland migration pressures and urban drift

Huniehu also announced the imminent engagement of an exploration group.

He said a Brisbane-based company, Geodiscovery Group, Prof Collerson and a co-consultant will work closely on the survey which should begin in August and would last six weeks.