DEEP-SEA MINING
Companies and countries are considering the potential of metal resources on the seafloor. Each jurisdiction has different regulations for its territorial waters. For example, to explore and mine for minerals in Australian waters, which is the offshore area beyond coastal waters starting three nautical miles from shore, companies must obtain an Offshore Mineral Licence. State or Territory permits are also generally required.
Some benefits of exploring copper and other minerals in the deep-sea environment are that the mineralisation is of favourable grade. In addition, resource definition is relatively easy, namely that it is essentially a 2D layer on the seabed.
The main minerals targeted in deep-sea mining today are manganese, copper and nickel. There are three main sources of these deep-sea minerals:
Polymetallic or manganese nodules — located in abyssal plains. These contain Ni, Cu, Co and Mn.
Cobalt-rich ferromanganese crusts (CRC) — formed at the flanks of seamounts. These contain up to 0.6 per cent Co + Mn, Cu, Ni +/- trace amounts of Li, Th, Te, Yt, Bi, REE, Nb and W.
Seafloor massive sulphides (SMS) — found near active and inactive hydrothermal vents. These contain Cu, Zn, Ag and Au. These are mined on the surface of the Earth as volcanic-hosted massive sulphide deposits.
Figure 26 shows the wide distribution of mineral resources in the deep sea demonstrating variation in resource size, distribution, and composition. One area of interest is nodule mining with sites covering 38 million km2 for manganese; 1.7 million km2 for cobalt-rich crusts; and 3.2 million km2 for seafloor massive sulphides.
Figure 26 - A distribution of select mineral resources in the deep sea. Note that the white areas around countries are Exclusive Economic Zones (EEZs), except for the white area around Antarctica, which is governed by an international commission
Many prospective mineral deposits are found on the vast seafloor abyssal plains in international waters. An area of particular interest is the Clarion-Clipperton Zone (CCZ) in the Pacific Ocean. This area already hosts exploration contracts for 17 deep-sea mining contractors, with their combined exploration areas covering approximately 1 million km2.
What Undersea Activity Can Be Undertaken Internationally?
The International Seabed Authority (ISA) was established under the United Nations Convention on the Law of the Sea 1982 (UNCLOS). It is an autonomous international organisation with the mandate to administer the mineral resources located on the seabed and subsoil beyond the limits of national jurisdictions.
The ISA has been awarding exploration contracts for seabed minerals since 2001 and is now developing a Mining Code. Its mandate is to ensure the effective protection of the marine environment from harmful effects that may arise from mining activities. The ISA has jurisdiction covering 54 per cent of the world’s ocean seabed.
No deep-sea mining operations have commenced anywhere in the world, although exploratory mining to test equipment has occurred at a small scale. Current exploration activities in the seabed area aim to gather information on the location and quality of minerals and collect the necessary environmental information. To date, ISA has approved 30 contracts for exploration involving 22 countries and covering more than 1.3 million km2. Twelve of these contracts are sponsored by developing countries.
In 2021, Nauru notified the ISA of plans to commence mining in international waters. This triggered a provision in UNCLOS known as the ‘two-year rule’, which requires that the ISA must consider and provisionally approve applications to mine, regardless of whether a final set of regulations has been agreed on. At the end of the two-year period, no final rule was in place and the ISA is now working with a view to adopt regulations by 2025.
After several years of discussions, the ISA is working to finalise regulations to control whether and how countries can pursue deep-sea mining in international waters. The ISA Mining Code will provide a regulatory framework for the exploitation of seabed mineral resources in international waters. It will reinforce the provisions of UNCLOS, especially those concerning the protection of the marine environment and marine biodiversity and life at sea.
While the ISA has until 2025 to establish a code for international waters, countries could still proceed with deep-sea mining projects in their own domestically controlled waters. Norway, for example, is planning to develop minerals within its exclusive economic zone and extended continental shelf.
While operational deep-sea mining is at an early stage of development, sea-bed minerals have long been considered as offering viable resource potential. As an example, in the 1970s feasibility testing work was done on polymetallic nodules as a metals resource. This work focused on the CCZ and was undertaken by companies including Kennecott Copper Corp, Ocean Management Inc and Deepsea Ventures Inc. This testing indicated technical feasibility of recovering these minerals from polymetallic nodules. Companies have been actively investigating the feasibility of deep-sea mining for at least 15 years.
Recovering Minerals From The Deep Sea
While technology is at an early stage of development, minerals could be extracted from the Deep Sea by a collector vehicle with a pickup mechanism that removes nodules with the upper layer of sediment as the vehicle manoeuvres on the abyssal seabed. This unit could have in-situ processing (sediment separation and sizing) and an onboard processor (dewatering and conditioning), meaning that polymetallic nodules could be separated from the sediment within the body of the collector vehicle. The nodules would then be transported to a surface operation vessel, and most of the sediment discharged in the vicinity of the collector. An example is shown in Figure 27.
Figure 27 - A schematic of a deep-sea mining operation
Key Challenges and Developments in Deep-sea Mining
There is some concern and awareness of the need to balance demand for minerals. There is some concern and awareness of the need to balance demand for minerals with activity that aligns with the UN SDGs. Terrestrial mining requires a small fraction of the areas compared to that needed at the seabed for economic recovery of ore resources. However, knowledge and research of potential impacts of deep-sea biodiversity and ecosystems is limited. Experts predict that many deep-sea species are unknown to science. Further research into the environmental impacts of deep-sea mining is required, and processes for rigorous environmental impact assessments need to be developed.
As an example, although modelling has been undertaken, no in-situ data is yet available to develop a physical understanding and quantification of the nature of sediment plumes near a collector vehicle.
Deep-sea mining requires a substantial upfront investment with the risk of unknown performance at the scale of the necessary technology. To date no extraction of metals from nodules has been undertaken at scale.
To address these challenges there are collaborative research efforts underway to better understand the deep-sea environment and potential impact of deep-sea mining, such as the Deep-sea Environmental and Social Impact Assessment (ESIA) program for Nauru Ocean Resources Inc. (NORI).
Companies such as The Metals Company are currently working on Environmental Impact Statements (EIS) to support feasibility studies that include assessments of the technical performance of prototype collection systems.
ISA is establishing a ‘DeepData’ database from contractors’ work for environmental baselines available for researchers and scientific stakeholders.
Areas of future research would likely be focused on extraction technologies and could include:
Use of filtration technology to extract valuable minerals, rather than whole rock extraction to the surface
Use of electrolysis to extract valuable minerals, rather than whole rock extraction to the surface
Use of drilling technologies and/or in-situ/in-place recovery to extract valuable minerals from solutions
Communication technologies to get data from the seafloor back to land.
There are also significant benefits from utilising the advances designed for deep-sea technology to benefit further exploration on land, especially in remote and difficult locations. Examples of technologies with land benefits include:
Sensors deployed on autonomous underwater drones (AUV) could be adapted for terrestrial purposes
Software and algorithms for mapping and locating polymetallic nodules efficiently
Adaptive management system prototypes for seabed mining providing real- time insights into the underwater environment and increased transparency of activity impacts.,
Further research into the environmental impacts of deep-sea mining is required, and processes for rigorous environmental impact assessments need to be developed.
OFF-EARTH MINING
The concept of off-Earth or space mining has been developing since 2007 with the establishment of Shackleton Energy Company. This US-based company was the first space mining company and focused on the Moon’s resource potential. Further companies have been founded to develop technologies to enable off-Earth mining, such as Deep Space Industries, Karman+, TransAstra, Astroforge and the Asteroid Mining Company. The interest in space resources was predominantly driven out of the US, with President Obama giving US citizens the right to own parts of celestial bodies.
The current motivation for off-Earth mining is the potential for an abundance of valuable minerals and the benefits of development of new technologies and processes to enable these missions, including spin-off technologies and capabilities that can be used in terrestrial operations.
Driving these is the overarching motivation of off-Earth colonisation and the recognition that local materials could be used to sustain off-Earth endeavours. In-situ resource utilisation (ISRU) or space resources utilisation (SRU) are examples where indigenous resources are converted into the various products needed for a space mission, reducing the amount of material that must be brought from Earth.
The current motivation for off-Earth mining is the potential for an abundance of valuable minerals.
The creation of a market for commodities in space is yet to happen and it is expected that water will be the first commodity. Organisations like the Luxembourg Space Agency (LSA) have forecast the opportunities for space resources utilisation, future markets and value chains (as shown in Figure 28), noting the time frame for these opportunities to be developed.
Figure 28 - The expected focus for off-Earth market development (Luxembourg Space Agency)
Off-Earth Resource Targets
According to NASA off-Earth mineral resource targets include:
Asteroids: There are more than 3 million minor planets that are rocky, airless remnants left over from the early formation of the solar system. However, these are no longer of interest because mining them in near-Earth orbit is currently technically and financially not feasible; moving them nearer Earth is risky; and the establishment of NASA’s Artemis campaign means there is now very little interest in asteroid mining, as NASA’s focus is the Moon and Mars.
Moon: Regolith, water, ice, and elements Hydrogen, Nitrogen, Oxygen, Rare Earth Elements, Yttrium, Lanthanum, Samarium, Helium are present on the Moon. To date, only very small concentrations of copper have been found.
Mars: Rock types include igneous basalt, sedimentary sandstone, mudstone, evaporite etc., and Mars has a solid core similar to Earth’s. Surface rocks look very similar to those in the Pilbara in Western Australia. Copper has been detected in samples.
As well as mineral potential in rocks on Mars, there is interest in the potential impact-related mineral resources on the planet. This could be similar to mineralisation that is understood to have occurred syngenetic to asteroid impact on Earth, for example the Sudbury Igneous Complex in Canada.
Tools developed for off-Earth exploration also have the potential to sharpen a terrestrial exploration tool kit.
Off-Earth Exploration Technology Development
Rovers: In the late 1990s-2000s, rovers became central to Mars exploration. Pathfinder’s Sojourner was the first, followed by the twin rovers Spirit and Opportunity. The missions transformed the understanding of Martian geology and climate history, with Opportunity discovering evidence of ancient liquid water flows on the Martian surface. The rover’s ability to traverse and analyse the Martian terrain provided information necessary for detailed geological studies. The Curiosity rover, part of NASA’s Mars Science Laboratory Mission, landed in 2012. It was equipped with technology to identify ingredients for potential past life and conduct more comprehensive scientific research than previous rovers.
Orbiters: A series of orbiters in the Martian sky have provided critical data about Mars’s atmosphere, climate and geology. NASA’s Mars Reconnaissance Orbiter’s HiRISE camera captured high-resolution images aiding the study of geological features, while the SHARAD instrument probed subsurface layers.
In the 2020s various Mars exploration missions took place including NASA’s Perseverance rover and Ingenuity helicopter. The helicopter became the first aircraft to achieve powered, controlled flight on another planet. Tools developed for off-Earth exploration also have the potential to sharpen a terrestrial exploration tool kit. For example, off-Earth solution must be robust, with adaptable suspension to navigate rocky irregular terrains. They need to mitigate against dust via protective layers on sensitive parts and possibly electrostatic or mechanical dust removal systems; and be thermally regulated, incorporating heaters and insulators to protect against cold and radiative surfaces to dissipate excessive heat.
Off-Earth solutions also require novel power solutions, such as hybrid propulsion systems integrating solar and nuclear power sources to ensure consistent and reliable energy supply.
Equipment that could be used on-Earth include miniaturised tools and sensors including advanced sensors. Laser-induced breakdown spectroscopy (LIBS) was first used by NASA’s Curiosity rover to analyse rocks. Rio Tinto is applying the technology in partnership with Finnish startup company Lumo Analytics. LIBS can deliver data on rock mineralogy and chemistry within 60 minutes of a scan and the tool collects about 2,000 readings a second with data on all elements in a sample. This reduces the amount of human error introduced by geologists in the identification of rocks creating an impartial dataset.
Off-Earth solutions may also bring new data processing capabilities, for example, to remove the effects of different atmospheric conditions. AI and ML for real-time terrain analysis and decision-making is also in development to ensure autonomous navigation and operation capabilities.
A current example of the terrestrial use of technology designed for off-Earth exploration is Eurasian Resources Group (ERG) early-stage exploration in Saudia Arabia based on data acquired by technology from NASA’s Mars Exploration rover mission, Nomad. Nomad incorporates a remote, all-wheel-drive semi-autonomous navigation system, a multi-sensor platform to scan samples and a soil drill that digs as deep as 80cm. ERG achieved a 400 per cent increase in operational efficiency compared with conventional manual exploration methods. Nomad is designed to operate in challenging terrains, like those found in Saudi Arabia.
Off-Earth endeavours also allow a unique perspective on Earth, such as NASA’s Earth Surface Mineral Dust Source Investigation (EMIT) which was launched to the International Space Station in 2022. EMIT is an imaging spectrometer that will produce the data to create comprehensive maps of a broad set of minerals across the Earth’s arid land regions.
Challenges Associated with Off-Earth Mining
Notwithstanding the developments in off-Earth technol- ogies there are numerous challenges associated with off-Earth mining exist. Off-Earth exploration begins with remote sensing observations from orbiting spacecraft capable of detecting the spectral signatures of minerals from space. There is currently minimal geological knowledge and very limited drilling data from Mars beyond 10cm depth. One challenge lies in distinguishing copper-bearing spectral signatures from other minerals with similar properties. Studies have reported spectral features associated with copper minerals in various regions of Mars, including crater floors, volcanic plains and sedimentary deposits. Laser-induced breakdown spectroscopy (LIBS) data from the SuperCam instrument on the Perseverance rover also indicated copper potential. Martian meteorite mineralogy and geochemistry have shown trace amounts of Cu bearing minerals, which is further evidence of potential, but this is not definitively confirmed.
A lack of standards also bring challenge to off-Earth mining. The Outer Space Treaty was developed in 1967, was developed to govern space activities. A total of 17 articles outlines permissible actions in space, however the Treaty lacks consideration of mining space resources. The more recent Artemis Accords, led by NASA, describe a shared vision for principles to create a safe and transparent facilitation of exploration, science, and commercial activities.
Space mining may be inevitable to support colonisation, and therefore, regulations must be established before extraction begins. International collaboration is necessary to develop the most beneficial and acceptable approach for off-Earth mining for humanity’s development. While market viability, economics, and accessibility may seem currently beyond reach, with the recent advent of private companies providing ‘space tourism,’ these aspects may see a shift in the future.
The Outer Space Treaty was developed in 1967, was developed to govern space activities.
The International space treaties remain untested regarding who would own the rights to minerals found in outer space, as most missions have been for scientific purposes.
Regulatory Considerations for Off-Earth Mining
Although several governments are undertaking off-Earth activities including NASA, the European Space Agency (ESA), the Japan Aerospace Exploration Agency (JAXA), the China National Space Administration (CNSA), the India Space Research Organisation (ISRO), the Luxembourg Space Agency (LSA), the Roscosmos State Corporation and others, it is considered more likely that it will be a commercial enterprise that leads off-Earth mining activity.
The International space treaties remain untested regarding who would own the rights to minerals found in outer space, as most missions have been for scientific purposes. For commercial space projects and space mining to be viable, future explorers and investors need to be certain of their rights regarding the extraction, consumption and commercialisation of the materials they discover. To that end, in 2017, Luxembourg became the first European country, and second worldwide, to offer a legal framework for the exploration and use of space resources.
The United Nations Committee on the Peaceful Uses of Outer Space (COPUOS) was established in 1959 to govern exploration and use of space and has established several treaties and principles. COPUOS also monitors the rapid evolution of technology; however, these will only apply to UN member states.
Centres with Off-Earth Mining Focus
A number of Australian research and industry centres have been established that include activity or focus on off-Earth mining or technology development.
Australian Centre for Space Engineering Research (ACSER) at UNSW, currently working with NASA on MARS mining processes;
Andy Thomas Centre for Space Resources (ATCSR) at the University of Adelaide;
The Australian Remote Operations for Space and Earth consortium (AROSE) which was established to bring knowledge and technology transfer between Australia’s traditional industry sectors and the international space sector;
The Innovative Launch, Automation, Novel Materials, Communications, and Hypersonics Hub (iLAuNCH) program, which is building Australia’s space capability through the commercialisation of projects, a fast-track accelerator, and skills development to build the workforce of the future;
Swinburne University Space Technology and Industry Institute reseraching astrophysics, aerospace, aviation, AI and other relevant sectors;
Curtin University’s Space Science and Technology Centre, collaborating with NASA and Lockheed Martin and leading the Murchison Widefield Array project, a low-frequency telescope in Western Australia.
