Technology Idea of the Week

Digging Deeper - The Deep Sea Gold Rush

Okay so this post was meant to go out two weeks ago but I have been defeated by blogger! So this is the tech idea for a couple of weeks ago and I will do another post this week with a new energy idea.

Hydrothermal vents located at ridges on the deep ocean floor were discovered in 1977 and our understanding of them is still fairly limited. They are home to a completely unique ecosystems: the microbes at the base of the food chain make energy by oxidising hydrogen sulphide which is produced by the vents (Lutz et al, Nature, 1994). This is fundamentally different to the production of energy by photosynthesis using carbon dioxide which sustains the vast majority of life. The vents sustain a variety of life including many organisms which cannot be found anywhere else on earth including giant tube worms (Riftia pachyptila) and the yeti crab (Kiwa hirsuta) - NewScientist, June 2011.

Riftia pachyptila - 2m long tube worms on the East Pacific Rise
Image Courtesy of NOAA Blogs

Kiwa hirsuta - the hairy legged yeti crab! Costa Rica.
Image Courtesy of MarineBiologene Blog

Shortly after the initial discovery of the vents, researchers began to investigate the mineral deposits located around them. There are significant concentrations of gold, silver, copper, zinc and manganese: all highly profitable minerals which many mining companies would be keen to exploit. 

There are many concerns from the scientific community about the effects on the endemic speices if exploration goes ahead. Many different articles have been published since the discovery of the mineral deposits about this issue. Halfur and Fujita, Science, 2011 argue that the disturbances to the ocean floor could release plumes of toxic chemicals that would damage the vent ecosystem and could have a widespread effect on ocean geochemistry. An editorial in Nature, 2011 also raises the issue about the direct impact on endemic species due to destruction of habitat and disturbance from mining operations. This is of particular concern because we know very little about the ecosystem and therefore cannot predict the impact we may have on it. Finally, there is huge concern about effecting the ecosystem because it has been suggested that these vents could be the location of the earliest life on Earth (Sousa et al, Royal Society, 2013). The environmental conditions around the vents could act as a proxy for the environment of the early earth therefore organisms around the vents could help us investigate the origins of life. If mining has a detrimental impact on these ecosystems it could damage biodiversity and scientific research. 

Bluewater Metals and Nautilus Minerals are two mining companies that are leading the way in mineral exploration in the Pacific Ocean. In 2011, Nautilus Minerals was granted a 20 year lease by the Papua New Guinea government to mine the Solwara 1 region in the Manus Basin (Dover, Nature, 2011). They are currently still investigating the area and predict that commercial production of minerals could begin as early as 2016 (BBC, 2013). The UN has just began to put together a framework for managing mineral extraction and licensing mining companies. This is managed by the UN International Seabed Authority. This map shows the Clarion-Clipperton Zone in the eastern Pacific which is currently being managed by the UNISA. There is estimated to be a total of 27 billion tonnes of mineral nodules (BBC, 2013). It is a little hard to see - here is the link to the full size image http://www.isa.org.jm/files/images/maps/CCZ-Sep2012-Official.jpg

The regions of the Clarion-Clipperton Zone
UNISA 2013

The key take away messages from the map are that the green striped areas represent the protected zones and the other colours all represent the licensed areas of different mining companies. It shows just how complicated the licensing in international waters and how close the environmental zones are to exploration areas. Very careful management is needed to preserve the ecosystem, maintain biodiversity and help continue scientific research into the origins of life. Mining of hydrothermal vents seems inevitable and I am more than a little concerned about its impacts on these extraordinary environments.

An interesting campagin group if you want to investigate further - Out of Our Depth