Geology for Global Development


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New mining frontiers: Digging into the unknown

New mining frontiers: Digging into the unknown

While climate change occupies the headlines as our biggest long-term concern for sustainability,  there may well be further anthropogenic challenges that arise in the next century as we disrupt the delicate interplay of natural ecological and geological cycles to satisfy the need for resources of our ever-growing population. The mining industry makes for a pertinent example: it sits on the verge of new key locations for digging – from the deep ocean to deep space – the consequences of which may not be fully explored.

The shift to a low-carbon economy is likely to entail an increase in demand for a wide variety of minerals. A 2017 report from the World Bank highlights the growth in demand for Lithium, Platinum and Lead, for new battery technology and rare earth element demand for solar and wind technology is also likely to increase.

As demand for these metals and resources rises, the cost and difficulty of extracting them rises too. Millennia of mining have exhausted the easy-to-access deposits for most metals, and the ratio of exploration sites that turn into actual mines is in the order of 1 in 1000. Combined with a decline in the overall quality of ore that is mined, it’s not hard to see why mining industry strategists are looking to previously unusable locations for their new mining ventures.

Geologists have known for a long time that the sea floor contains extensive mineral deposits of a wide variety of types; from ferro-manganese nodules to ores linked to submarine volcanism, economic minerals are spread across the global ocean floor. Until recently, the economics of dredging these sea beds for minerals have not been favourable, and technology has been too rudimentary to make an effective industry out of this approach. Now, however, prices and demand for these minerals are high enough that seafloor mining is beginning to take place in a few locations around the world.

Extraction like this could, of course, have major consequences. Biodiversity in the deep ocean is, even today, poorly understood, so strip mining these systems before we explore them fully could cause untold damage. At a small scale, this kind of mining might only have more limited, local impacts, but for the first time in the history of human society we have the capability to affect biological systems and geological cycles at a global scale, to a degree that might have significant and deleterious effects.

For example, mining waste on land can lead to contamination of local water supplies with acidic runoff. Deep sea mining could similarly lead to acidification of sea water, which could have far reaching consequences. Marine creatures living in the ocean are often very finely tuned to the chemistry of the water they’re bathed in; even small changes in acidity have been linked to increased coral bleaching and death. The risk of heavy metal pollution has also been pointed out from sand and mud kicked up by mining activity as it disturbs the sea bed; these toxic metals could cause problems both the sea life and to humans, as the fishery stocks would become increasingly exposed to heavy metals. The global extent of ocean currents mean that these effects wouldn’t be limited to the vicinity of the mining, as chemicals would be mixed into the whole ocean over time.

Unlike mining on the surface, the spread of this kind of pollution could be truly global; ocean currents could eventually spread the pollutants, and the mining itself would hardly be limited to a specific locality. Humans are poorly positioned to deal with this kind of crisis; a negative impact on the ocean – a global resource, not owned by any individual nation state – is a classic ‘tragedy of the commons’, much like carbon dioxide accumulation in the atmosphere. Given the lack of ownership of the oceans, individual states or mining companies lack strong incentives to regulate the exploitation of such sea-floor resources. Moreover, the globalised nature of the extractive industry means this could be a truly significant impact; the combined revenue of the top 40 surface mining companies is approximately half a trillion dollars, dwarfing all but the largest national economies, affording such corporations major financial clout to explore and develop mining on the sea floor.

At the dawn of the fossil fuel era in the Industrial revolution, the risks of burning coal, and later oil and gas, were poorly understood in comparison to today. Some authors suggest that since we are now much more aware of environmental issues, we are better placed to assess the future risks and rewards of deep sea mining than the earlier resources for which we mined and drilled.

It is perhaps worth pointing out, though, that with the range out impacts still poorly constrained even as dredging begins, it is incumbent upon geologists to explore and quantify the potential risks; academic research must keep pace with the growth of industry.

Even if deep sea mining does not have major, long-lasting impacts, there is one other mining frontier for which the risks are nearly totally unconstrained: asteroids.

It may sound like science fiction, but serious consideration is being given to mineral resources on near Earth asteroids. Given their potential value (some estimates – of the asteroid Psyche suggest mineral resources worth a quintillion dollars – an amount of money that’s basically inconceivable), it’s not surprising that enterprising drillers are looking up, as well as to the sea floor. Again, though, research into the potential geological hazards needs to be undertaken well before such ventures are carried out.

Our ever increasing environmental footprint has the potential to spread to new and poorly studied horizons, and we should endeavour not to make the same mistakes as we did with fossil fuels.

Robert Emberson is a science writer, currently based in Vancouver, Canada. He can be contacted via Twitter (@RobertEmberson) or via his website (

**This article expresses the personal opinion of the author. These opinions may not reflect official policy positions of Geology for Global Development.**

Circular economy of metals and responsible mining

Circular economy of metals and responsible mining

In today’s post, Bárbara Zambelli, considers how we can transition business models towards a more sustainable way of living, manufacturing and consuming.

As I mentioned before in my post about Urban Geology and Underground Urbanisation, according to the UN report, the current world population of 7.6 billion is expected to reach 8.6 billion in 2030 and 9.8 billion in 2050. In addition, the percentage of the world’s population living in urban areas is growing steadily. In this scenario, it is possible to state that population growth and urbanisation are strongly correlated to mineral and metal consumption. In developed countries, the demand for metals is expected to remain strong to keep up with modern technologies and, in developing countries, due to rapid industrialisation and urbanisation.

Minerals and metals are required as materials for infrastructure and constructions (e.g. aggregates, cement, iron, steel, aluminium, copper, alloys), implements for agriculture (e.g. phosphorus and limestone) and essential components of “green” technologies such as solar panels and wind energy (lithium, cobalt, cadmium, REE). The increased consumption we face nowadays requires a great amount of metals which cannot be supplied by natural resources. We already consume more than we can replace and our finite resources are being depleted.

In this context, circular economy represents a way of conceptualizing and operationalizing the transition of business models towards a more sustainable way of living, manufacturing and consuming.

What is circular economy?

Generally, it can be understood as a “cyclical closed-loop system”.

The United Nations Environmental Programme defines circular economy as “one which balances economic development with environmental and resource protection, with the aims to ‘design out’ waste, return nutrients and recycle durables, using renewable energy to power the economy”.

A really interesting paper discusses the concepts and applications of circular economy in Global context, its tensions and limitations.

The authors proposed the redefinition for circular economy as “an economic model wherein planning, resourcing, procurement, production and  reprocessing are designed and managed, as both process and output, to maximize ecosystem functioning and human well-being”.

Circular economy opposes the model of linear economy, in which natural resources are turned into waste via production. It assumes unlimited supply of natural resources and unlimited capacity of the environment to absorb waste. On the other hand, circular economy is conceived as having no net effect on the environment, furthermore, it ensures little generation of waste during the production process. The circular economy relies on the idea of recycling products, using waste as resources, helping to tackle unsustainable patterns of production and consumption.

China is the pioneer in the implementation and development of circular economy strategy at national level. With almost 1.4 billion people (around 19% of the world figure), it is of vital interest worldwide that China adopts economic and sustainable business practices. Moreover, other parts of the world are adopting the concept of circular economy to keep resources in economic use for as long as possible. To give some examples, there is the UK initiative Ellen MacArthur Foundation, founded in 2010. In 2014, the European Commision launched  their own programme named Towards a Circular Economy: a zero waste programme for Europe. In Brazil also there are projects like this, developed into the Federal University of Santa Catarina to promote the circular economy.

However circular economy may seems to solve our problems regarding raw materials and metals supply, that are some important points to highlight. It is crucial to take into account the metal cycles and flows in the system of each metal to understand the environmental impacts associated to each phase of the cycle, since raw material extraction to the end of life. Another important feature is that circular economy relies on metallurgy, technology and understanding of product design (mineralogy). The recovery rate of each metal depends on the combination of those three factors. In addition, there are some companies recycling atoms for some metals, although these processes are energy-intensive and recover the metals part-only.

Despite the idea of designing products that last much longer appears useful, longevity is not always efficient ecologically. The issue of flux should be central and procrastinating the cycle through exotic chemistry may not be an appropriate strategy.

Finally, even though circular economy has an amazing potential for reducing the need of raw materials, stop mining primary resources is nearly impossible. In this manner, we should promote responsible mining when circular economy is not applicable.

Climate migration needs to be predicted and planned now. Geoengineering can slow down sea level rise but could also lead to international conflicts. CO2 as a natural resource. All in Jesse Zondervan’s Mar 8 – Apr 4 2018

Climate migration needs to be predicted and planned now. Geoengineering can slow down sea level rise but could also lead to international conflicts. CO2 as a natural resource. All in Jesse Zondervan’s Mar 8  – Apr 4 2018

Each month, Jesse Zondervan picks his favourite posts from geoscience and development blogs/news which cover the geology for global development interest. Here’s a round-up of Jesse’s selections for the last month:

Imagine 140 million people across sub-Saharan Africa, south Asia and Latin America migrating in response to climate change effect, by 2050. This is what a recent World Bank report claims, by projecting current internal migration patterns due to effects, like coastal land loss and crop failure, into the future using climate models.

Climate migration will tend to be mostly internal to countries and can foster inequality as well as economic loss. Since it’s inevitable, we will need to plan for it.

We cannot prevent climate migration, but geoengineering will be a very powerful way to combat unnecessary increases in damage from climate change. With this power comes responsibility through. What will happen if one country decides to spray aerosols to decrease temperature, and inadvertently changes things for the worse for another region?

So yes, we need laws on geoengineering to prevent battles over well-meant geoengineering failures. Interestingly, I found a lot of research articles with new geoengineering proposals, so it’s really coming soon, and we need to think about regulation now.

Geoengineering can be costly. Pumping carbon dioxide from the atmosphere may prevent crop failures due to elevated temperatures, but it is still expensive. But what if we could use CO2 as a natural resource? A team of US and Canadian scientists say it will be possible to use captured CO2 for feedstock, biofuels, pharmaceuticals, or renewable fuels.

This month you will find an article under the section ‘career’, which you should have a look at if you’re doing or thinking of doing a PhD and you want to consider working outside academia. You will find a lot of articles under the usual headings too, so go ahead!


Once we can capture CO2 emissions, here’s what we could do with it at ScienceDaily by Sarah Fecht at State of the Planet

Preventing hurricanes using air bubbles at ScienceDaily

Geoengineering polar glaciers to slow sea-level rise at ScienceDaily

Mekong River dams could disrupt lives, environment at ScienceDaily

Climate Migration

Wave of Climate Migration Looms, but It “Doesn’t Have to Be a Crisis” by Andrea Thompson at Scientific American

Addressing Climate Migration Within Borders Helps Countries Plan, Mitigate Effects by Alex de Sherbinin at State of the Planet

Having an impact as a development economist outside of a research university: Interview with Alix Zwane by David McKenzie at Development Impact


Structuring collaboration between municipalities and academics: testing a model for transdisciplinary sustainability projects at Lund University

To Sustain Peace, UN Should Embrace Complexity and Be UN-Heroic by Peter Coleman at State of the Planet

Climate Change Adaptation

The Rise of Cities in the Battle Against Climate Change by Allison Bridges at State of the Planet

A City’s Challenge of Dealing with Sea Level Rise at AGU’s Eos

The absence of ants: Entomologist confirms first Saharan farming 10,000 years ago at ScienceDaily

Turning cities into sponges: how Chinese ancient wisdom is taking on climate change by Brigid Delaney at The Guardian

Risk of sea-level rise: high stakes for East Asia & Pacific region countries by Susmita Dasgupta at East Asia & Pacific on the Rise

National Flood Insurance Is Underwater Because of Outdated Science by Jen Schwartz at Scientific American

Disaster Risk

Mobile phones and AI vie to update early disaster warning systems by Nick Fildes at The Financial Times

7 years after tsunami, Japanese live uneasily with seawalls by Megumi Lim at Japan Today

Volcanic risk

GeoTalk: How will large Icelandic eruptions affect us and our environment? By Olivia Trani at EGU’s GeoLog

Earthquake risk

The Wicked Problem of Earthquake Hazard in Developing Countries at AGU’s Eos

External Opportunities

Summer 2018 Internship Opportunities at the Earth Institute

Check back next month for more picks!

Follow Jesse Zondervan @JesseZondervan. Follow us @Geo_Dev& Facebook.

Weighing up the pros and cons of artificial coral reefs

Weighing up the pros and cons of artificial coral reefs

The world’s oceans cover 71% of the Earth’s surface and contain 97% of Earth’s water. They play a key role in the climate cycle and, though perhaps not always visibly, are suffering significantly under our changing climate. An place where we can see the alarming effects of rising temperatures and increasingly acidic waters is coral reefs, which experienced the longest, most widespread, and possibly the most damaging coral bleaching event on record between 2014 and 2017. In today’s post, Heather Britton compares natural vs. artificial coral reefs in the context of protecting life below the water (UN sustainability goal 14).

Reefs around the world are dying – approximately half of the world’s coral reefs have disappeared over the past 30 years, and many are showing signs of following in their stead – be it due to increased water temperature, sea level change or an influx of sediment in previously nutrient-poor conditions. Many of the factors contributing to the bleaching and eventual death of these ecosystems stem from the impact of people, such as global warming and the development of resorts in the vicinity of fragile reef environments.

The disappearance of coral reefs would lead to a catastrophic loss of biodiversity – coral reefs are thought to be the most biodiverse ecosystems on the planet, displaying a greater variety of life than even rainforests, and it is clear that we need to act now if these environments are to be saved – for many reefs it is already too late.

One popular response to the loss of natural coral reefs has been to construct artificial reefs, replacing those that have died and providing a habitat for organisms that may otherwise become extinct. These structures take a plethora of forms, from sunken ships to cinder block stacks, but as long as they are made of a hard substrate and are able to offer protection and a place for sheltering organisms to spawn there is potential for a reef to develop in as little as two-three years.

In many ways, this is an elegant solution. Not only do artificial reefs help to combat the loss of biodiversity associated with the decline of their natural counterparts, but they attract divers and other tourists to the sites where they are placed, bringing in tourism and strengthening the economy in the area. This benefit is particularly valuable to lower income countries, some of which boast extensive coral reef ecosystems. In addition, reefs are known to concentrate fish populations and therefore are popular with the fishing industry worldwide – the first recorded artificial reefs were developed by fishermen in Japan in the 18th century, who sunk makeshift shelters to increase their haul. Reefs form from man-made substrates relatively easily, and they are certainly preferable to a lack of reefs altogether – but can artificial reefs really ever match their natural cousins?

Diver installing ocean-chemistry monitoring equipment at Florida Keys. Credit: Ilsa B. Kuffner (U.S. Geological Survey). Distributed via U.S. Geological Survey. 

Artificial reefs are created extensively off the coast of Florida, as much for the economic benefit that the tourism brings (both through fishing and diving) as increasing ocean biodiversity. The region is encountering problems, however, one of which is local people choosing to develop their own personal reefs using suboptimal materials. For example, tyres, when strapped together, attract aquatic organisms as they provide a place to spawn and the shelter of a natural reef, but the toxicity of the rubber can negatively impact the environment in ways that a ship or concrete blocks will not. Ships that are sunk professionally for the purpose of artificial reef formation are extensively prepared before they are placed underwater, whereas amateurs rarely take the time to prepare their seeding structures properly. This has led some countries, such as Australia, to develop laws against the formation of artificial reefs without a permit.

Artificial reefs are also celebrated because they attract divers away from the surviving natural reefs, meaning that each individual reef is less damaged by people. It is also possible, however, that the number of tourists in total might increase in response to the increased number of dive-sites, having the opposite effect and causing dive sites in the region to become more popular.

Arguably, the most important question to be asked when discussing natural vs artificial reef structures is: do artificial reefs have biodiversity equivalent to that of natural reefs? The answer is unclear, but it certainly seems that the biodiversity of each kind of reef is different. Artificial reefs, at first glance, seem to attract more fish to them than natural reefs. This suggests that that artificial reefs may be encouraging fish to reproduce more than the naturally occurring reefs scattered throughout the oceans. However, many of the marine animals attracted to feed and shelter around artificial reefs do not breed there, and simply visit from other regions of the ocean. Artificial reefs therefore may only be acting to concentrate the fish in a single area, making them more susceptible to fishing and generally increasing the effect of fishing pressure on marine populations. This is commonly referred to as the ‘aggregation vs production’ debate. If the fish are more numerous at artificial reefs because they are breeding there, then the reef is likely acting to increase the population of that particular fish species and artificial reefs are helping to sustain the biodiversity of the oceans. If they are simply concentrating fish that typically spend their time swimming between reefs, however, fish numbers are likely to be negatively, not positively affected.

Dead corals turned to rubble, off the coast of the US Virgin Islands. Credit: Curt Storlazzi (U.S. Geological Survey). Distributed via U.S. Geological Survey.

A study on the Caribbean island of Bonaire provides some insight into the differences in diversity between natural and artificial reefs. Equal diversity was found at partnered artificial and natural reefs, but the composition of this diversity was starkly different. Whilst the sergeant major and bluehead wrasse fish were most commonly seen on the artificial reef, the natural was more commonly frequented by bicoloured damselfish and brown chromis. Similar trends were visible within the benthic community of organisms, suggesting that although artificial reefs may preserve the diversity that we see within the oceans today, some organisms appear to populate natural reefs to a far greater extent than their artificial counterparts, and these species may still be lost.

For this reason it is of the utmost importance that every effort is made to protect the natural coral reefs of today, thereby working to achieve UN sustainability goal 14 (Life below the Water). Artificial reefs are helping to preserve the biodiversity of the oceans and save countless organisms from extinction, but it is important to remember that what causes the corals of natural reefs to die will also impact the corals which begin to grow on artificial reefs. In order to prevent the loss of these ecosystems we need get to the root of the problem and combat the things that are harming coral reefs – global warming, human physical destruction of reef environments and the pollution of our oceans.