Latest news with #geochemist
CNN
12-08-2025
- Science
- CNN
Scientists say they cruised the ocean in a deep-sea submersible and came across an undiscovered ecosystem
FacebookTweetLink Marine researchers exploring extreme depths say they have discovered an astonishing deep-sea ecosystem of chemosynthetic life that's fueled by gases escaping from fractures in the ocean bed. The expedition revealed methane-producing microbes and marine invertebrates that make their home in unforgiving conditions where the sun's rays don't reach, according to a new study. Geochemist Mengran Du had 30 minutes left in her submersible mission when she decided to explore one last stretch of the trenches that lie between Russia and Alaska, about 5,800 to 9,500 meters (19,000 to 30,000 feet) below the ocean's surface in what's called the hadal zone. She said she began to notice 'amazing creatures,' including various species of clam and tube worm that had never been recorded so deep below the surface. What Du stumbled upon was a roughly 2,500-kilometer (1,550-mile) stretch of what her team says is the deepest known ecosystem of organisms that use the chemical compound methane instead of sunlight to survive. Du is a co-lead author of a study describing the findings that was published July 30 in the journal Nature. The hadal zone is primarily comprised of oceanic trenches and troughs — some of the deepest and least explored environments on Earth. At these depths, 'life needs tricks to survive and thrive there,' explained Du, a professor and researcher at the Institute of Deep-sea Science and Engineering at the Chinese Academy of Sciences. One of those tricks lies in bacteria that have evolved to live inside the clams and tube worms, according to the National Oceanic Atmospheric Administration. The bacteria convert methane and hydrogen sulfide from cold seeps — cracks in the seafloor that leak these compounds as fluids — into energy and food that the host animal can use, allowing organisms to live in zero-sunlight conditions. The discovery suggests that these communities might also exist in other hadal trenches, Du said, opening opportunities for further research into just how deep these animals can survive. After analyzing sediment samples collected from the expedition, Du and her team said they detected high concentrations of methane. The find was surprising, since deep-sea sediments normally contain very low concentrations of the compound. The scientists hypothesized that microbes living in the ecosystem convert organic matter in the sediments into carbon dioxide, and carbon dioxide into methane — something the researchers didn't know microbes could do. The bacteria living inside clam and tube worm species then use this methane for chemosynthesis to survive, Du said. There was another revelation, too. Scientists previously thought chemosynthetic communities relied on organic matter — such as from dead organisms and drifting particles from living species — that fell from the ocean's surface to the floor. But this discovery, Du said, reveals that these methane-producing microbes are also creating a local source of organic molecules that larger organisms such as clams can use for food and energy. Methane, as a carbon-containing compound, is part of the carbon cycle. So, this discovery also indicates that the hadal trenches play a more important role in that cycle than previously thought, Du explained. Scientists have long understood that methane is stored as compressed fluid deep in the subduction zone, where tectonic plates meet below the ocean floor, which ultimately releases through 'cold seeps' at the bottom of hadal trenches. Now that Du's team has discovered chemosynthesis at such depths, they hypothesize that the hadal trenches act not only as reservoirs, but also as recycling centers for methane. This suggests, Du said, that 'a large amount of the carbon stays in the sediments and (is) recycled by the microorganisms.' Indeed, scientists have recently estimated that hadal zone sediments could sequester as much as 70 times more organic carbon than the surrounding seafloor. These so-called carbon sinks are crucial for our planet given that methane and carbon dioxide are two major greenhouse gases driving global warming in the atmosphere. Chemosynthetic communities themselves are not new to science. Previous research has hinted that it was possible for them to thrive at such great depths, said Johanna Weston, a deep ocean ecologist at Woods Hole Oceanographic Institute in Massachusetts who was not involved with the new study. She was impressed, however, with the extent of the recent discovery, she told CNN. In an age of widespread biodiversity loss, the finding highlights the importance of new technology that can withstand high pressure in deep-sea environments to document undiscovered organisms, said Weston, who is part of a team actively exploring the deep-sea offshore from Argentina. Even though the hadal trenches are remote, they aren't completely isolated, she added. Weston and her colleagues discovered a newfound species in 2020 in the Mariana Trench named Eurythenes plasticus for the microplastic fibers detected in its gut. And near Puerto Rico, Weston newly identified an isopod that exclusively eats sargassum, a type of abundant seaweed in the Atlantic Ocean that can sink to the ocean floor in just 40 hours. 'The deep ocean is very connected to what's happening on the surface,' she said. Research on deep-sea ecosystems is only a few decades old, and the technology for new discoveries is improving. But Du added that it's important for different countries and scientific disciplines to collaborate on future efforts. The Global Hadal Exploration Program, which is co-led by UNESCO and the Chinese Academy of Sciences, aims to do just that by creating a network of deep-sea scientists from multiple countries. Du hopes she and her team can learn more about hadal trench ecosystems by studying how these species have adapted to such extreme depths. 'Even though we see the hadal trench as a very extreme environment, the most inhospitable environment … (chemosynthetic organisms) can live happily there,' Du said. Sign up for CNN's Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more.
Daily Mail
25-06-2025
- Science
- Daily Mail
Africa is tearing in HALF: Scientists detect deep Earth pulses beneath Ethiopia - in ominous sign that the entire continent could rupture
We know that all of the world's continents are constantly moving. But one of them has already begun a dramatic transformation. Scientists say a massive crack has started ripping through Africa, from the north east to the south. The experts uncovered evidence of rhythmic surges of molten rock rising from deep within the Earth's surface, beneath Ethiopia. These pulses are gradually tearing the continent apart and forming a new ocean – although it's happening so slowly it's basically imperceptible. 'The split will eventually go all the way down Africa,' lead author Dr Emma Watts, a geochemist at Swansea University, told MailOnline. 'It has already begun and is happening now but at a slow rate – 5-16 mm per year – in the north of the rift. 'Regarding timescales, this process of Africa being torn apart will take several million years before it is completed.' Dr Watts and colleagues point to the Gulf of Aden, a relatively narrow body of water separating Africa in the south and Yemen in the north. Like a small tear in a piece of clothing, the gradual separation event could start at the Gulf of Aden and gradually spread downwards. As it does so, it would split through the middle of enormous bodies of water in East Africa, such as Lake Malawi and Lake Turkana. By the time the split is complete, several million years from now, Africa would be made up of two landmasses. There would be the larger landmass in the west featuring most of the 54 modern-day African countries, such as Egypt, Algeria, Nigeria, Ghana and Nambia. Meanwhile, the smaller landmass to the east will include Somalia, Kenya, Tanzania, Mozambique and a large portion of Ethiopia. 'The smaller part that breaks away towards the east will be approximately 1 million square miles in area,' Dr Watts told MailOnline. 'And the remaining larger landmass will be just over 10 million square miles.' The layers of Earth Crust: To a depth of up to 43 miles (70km), this is the outermost layer of the Earth, covering both ocean and land areas. Mantle: Going down to 1,795 miles (2,890km) with the lower mantle, this is the planet's thickest layer and made of silicate rocks richer in iron and magnesium than the crust overhead. Outer core: Running to a depth of 3,200 miles (5,150km), this region is made of liquid iron and nickel with trace lighter elements. Inner core: Going down to a depth of 3,958 miles (6,370km) at the very centre of Earth, this region is thought to be made of solid iron and nickel. For the study, the team collected more than 130 volcanic rock samples from across the Afar region. In this region, three tectonic plates converge (the Main Ethiopian Rift, the Red Sea Rift and the Gulf of Aden Rift), making it a hotbed of volcanic activity. The experts used these samples, plus existing data and advanced statistical modelling, to investigate the structure of the Earth's crust and the mantle below it. The mantle, the planet's thickest layer, is predominantly a solid rock but behaves like a viscous fluid. 'We found that the mantle beneath Afar is not uniform or stationary – it pulses,' said Dr Watts. 'These ascending pulses of partially molten mantle are channelled by the rifting plates above.' Over millions of years, as tectonic plates are pulled apart at rift zones like Afar, they stretch and thin – almost like soft plasticine – until they rupture, marking the birth of a new ocean. Geologists have long suspected that a hot upwelling of mantle, but until now, little was known about the structure of this upwelling, or how it behaves beneath rifting plates. The team say the pulses appear to behave differently depending on the thickness of the plate, and how fast it's pulling apart. The findings, published in Nature Geoscience, show that the mantle plume beneath the Afar region is not static, but dynamic and responsive to the tectonic plate above it. 'We have found that the evolution of deep mantle upwellings is intimately tied to the motion of the plates above,' said co-author Dr Derek Keir, associate professor in earth science at the University of Southampton and the University of Florence. 'This has profound implications for how we interpret surface volcanism, earthquake activity, and the process of continental breakup. 'The work shows that deep mantle upwellings can flow beneath the base of tectonic plates and help to focus volcanic activity to where the tectonic plate is thinnest. 'Follow on research includes understanding how and at what rate mantle flow occurs beneath plates.' The Earth is moving under our feet: Tectonic plates move through the mantle and produce Earthquakes as they scrape against each other Tectonic plates are composed of Earth's crust and the uppermost portion of the mantle. Below is the asthenosphere: the warm, viscous conveyor belt of rock on which tectonic plates ride. Earthquakes typically occur at the boundaries of tectonic plates, where one plate dips below another, thrusts another upward, or where plate edges scrape alongside each other. Earthquakes rarely occur in the middle of plates, but they can happen when ancient faults or rifts far below the surface reactivate.
Yahoo
06-05-2025
- Science
- Yahoo
How the US can mine its own critical minerals − without digging new holes
Every time you use your phone, open your computer or listen to your favorite music on AirPods, you are relying on critical minerals. These materials are the tiny building blocks powering modern life. From lithium, cobalt, nickel and graphite in batteries to gallium in telecommunication systems that enable constant connectivity, critical minerals act as the essential vitamins of modern technology: small in volume but vital to function. Yet the U.S. depends heavily on imports for most critical materials. In 2024 the U.S. imported 80% of rare earth elements it used, 100% of gallium and natural graphite, and 48% to 76% of lithium, nickel and cobalt, to name a few. Rising global demand, high import dependency and growing geopolitical tensions have made critical mineral supply an increasing national security concern − and one of the most urgent supply chain challenges of our time. That raises a question: Could the U.S. mine and process more critical minerals at home? As a geochemist who leads Georgia Tech's Center for Critical Mineral Solutions and an engineer focused on energy innovation, we have been exploring the options and barriers for U.S. critical mineral production. What's stopping critical minerals from being produced domestically? Let's take a look at rare earth elements. These elements are essential to modern technology, electric vehicles, energy systems and military applications. For example, neodymium is critical for making the strong magnets used in computer hard discs, lasers and wind turbines. Gadolinium is vital for MRI machines, while samarium and cerium play key roles in nuclear reactors and energy systems such as solar and wind power. Despite their name, rare earth elements are actually not rare. Their concentrations in the Earth's crust are comparable to more commonly mined metals such as zinc and copper. However, rare earth elements do not often occur in easily accessible, economically viable mineral forms or high-grade deposits. As a result, identifying resources with sufficiently high concentration and large volume is crucial for enabling their economic production. CC BY-SA MP Materials' Mountain Pass Rare Earth Mine and Processing Facility is in California near the Nevada border. Tmy350/Wikimedia Commons The U.S. currently has only two domestic rare earth mining locations: Georgia and California. In southeast Georgia, rare earths are being produced as a byproduct of heavy mineral sand mining, but the produced rare earth concentrates are shipped out of state and then abroad for refining into the materials used in renewable energy technologies and permanent magnets. The other location is in Mountain Pass, California, where hard rock mining extracts a rare earth carbonate mineral called bastnaesite. Yet again, much of the material is sent abroad for refining. As a result, the entire supply chain − from mining to final use in products − stretches across continents. Meeting the U.S. demand for rare earth elements and other critical minerals from operations within the United States will require more than just opening new mines. It will require developing and scaling up new technologies, as well as building processing operations. Historically, processing has largely taken place overseas because of the environmental impacts, energy demand and regulatory constraints. The potential, but long road, to new mines Investment in exploration activity for critical minerals is rapidly increasing across the U.S. In 2017 the U.S. Geological Survey launched the Earth Mapping Resources Initiative − known as Earth MRI − to identify potential sources of critical minerals within the country. Some areas that appear promising for rare earth elements have lots of chemical weathering, in which rocks containing rare earth elements are broken down by reacting with water and air. Exploration is underway at several of these sites, including in locations in Wyoming and Montana. A map shows focus areas for 23 mineral systems that could have critical mineral resources. USGS Identifying a resource, however, is not the same as producing it. Traditional mining can take a decade or two from exploration to production and up to 29 years in the U.S., the second-longest timeline in the world. Although this timeline could be changing under the current administration, companies might still face major uncertainties related to permitting, infrastructure development and, in some places, community opposition. Managing environmental impacts, such as air and water pollution and high water consumption and energy use, can further increase cost and extend project timelines. Given that the exploration projects mentioned above are still in early stage, the U.S. needs additional, parallel efforts that can bring resources to the market at an accelerated pace. Mining the materials we have already mined One of the fastest ways to increase U.S. rare earth production may not require digging new holes in the ground − but rather returning to old ones. The Atlantic coast region stands out on the Earth MRI map as a particularly promising area. What's even better is that this region has already established extensive mining activities and mature infrastructure, which allows for much faster speed to market. Georgia has mineral sand deposits that are rich in titanium, zirconium, and rare earth elements. Titanium and zirconium − both used in aerospace, energy and medical applications − are already mined in Florida and Georgia. In southeast Georgia, rare earth elements found with these heavy mineral sands are already being recovered as rare earth concentrates. Kaolin, a white clay used in paper, paint and porcelain, has been mined in Georgia for over a century, and it can also contain rare earth elements. Georgia generates more than 8 million tons of kaolin annually, making it the leading U.S. producer and a large exporter. This also comes with millions of tons of mining and processing residues, or what's known as tailings. Recent research studies suggest that there is significant potential for extracting rare earth elements in the tailings. The tailings are already mined and sitting on the surface. There is no need to drill or blast. That means existing infrastructure, faster timelines and lower costs and than new mining operations. Technological innovations, such as bioleaching, ligand-based extraction and separation and electrochemical separation, are now making mining these legacy wastes possible. New processing facilities could be built near existing kaolin or heavy mineral sand operations or former mine sites, bringing materials to market in a few years rather than decades. The future of waste mining This approach is part of a broader strategy known as 'waste mining,' 'urban mining' or 'mining the anthropogenic cycle.' It involves the recovery of critical minerals from existing waste streams such as mine tailings, coal ash and industrial byproducts. It is also part of building a circular economy, where materials are reused and recycled rather than discarded. The U.S. has the potential to catalyze new domestic supply chains for materials essential to national security and technology. Waste mining and recycling are critical pieces to ensure the long-term sustainability of these supply chains. The authors do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.
