Latest news with #JacksonSchool
Yahoo
04-07-2025
- Science
- Yahoo
Could signs of Mars life be hidden in its thick layers of clay?
When you buy through links on our articles, Future and its syndication partners may earn a commission. The thick, mineral-rich layers of clay found on Mars suggest that the Red Planet harbored potentially life-hosting environments for long stretches in the ancient past, a new study suggests. Clays need liquid water to form. These layers are hundreds of feet thick and are thought to have formed roughly 3.7 billion years ago, under warmer and wetter conditions than currently prevail on Mars. "These areas have a lot of water but not a lot of topographic uplift, so they're very stable," study co-author Rhianna Moore, who conducted the research as a postdoctoral fellow at the University of Texas' Jackson School of Geosciences, said in a statement. "If you have stable terrain, you're not messing up your potentially habitable environments," Moore added. "Favorable conditions might be able to be sustained for longer periods of time." On our home planet, such deposits form under specific landscape and climatic conditions. "On Earth, the places where we tend to see the thickest clay mineral sequences are in humid environments, and those with minimal physical erosion that can strip away newly created weathering products," said co-author Tim Goudge, an assistant professor at the Jackson School's Department of Earth and Planetary Sciences. However, it remains unclear how Mars' local and global topography, along with its past climate activity, influenced surface weathering and the formation of clay layers. Using data and images from NASA's Mars Reconnaissance Orbiter — the second-longest-operating spacecraft around Mars, after the agency's 2001 Mars Odyssey — Moore, Goudge, and their colleagues studied 150 clay deposits, looking at their shapes and locations, and how close they are to other features like ancient lakes or rivers. They found that the clays are mostly located in low areas near ancient lakes, but not close to valleys where water once flowed strongly. This mix of gentle chemical changes and less intense physical erosion helped the clays stay preserved over time. "[Clay mineral-bearing stratigraphies] tend to occur in areas where chemical weathering was favoured over physical erosion, farther from valley network activity and nearer standing bodies of water," the team wrote in the new study, which was published in the journal Nature Astronomy on June 16. The findings suggest that intense chemical weathering on Mars may have disrupted the usual balance between weathering and climate. RELATED STORIES — NASA's Curiosity Mars rover discovers evidence of ripples from an ancient Red Planet lake (images) — Ocean's worth of water may be buried within Mars — We finally know where to look for life on Mars On Earth, where tectonic activity constantly exposes fresh rock to the atmosphere, carbonate minerals like limestone form when rock reacts with water and carbon dioxide (CO2). This process helps remove CO2 from the air, storing it in solid form and helping regulate the climate over long periods. On Mars, tectonic activity is non-existent, leading to a lack of carbonate minerals and minimal removal of CO2 from the planet's thin atmosphere. As a result, CO2 released by Martian volcanoes long ago likely stayed in the atmosphere longer, making the planet warmer and wetter in the past — conditions the team believes may have encouraged the clay's formation. The researchers also speculate that the clay could have absorbed water and trapped chemical byproducts like cations, preventing them from spreading and reacting with the surrounding rock to form carbonates that remain trapped and unable to leech into the surrounding environment. "[The clay is] probably one of many factors that's contributing to this weird lack of predicted carbonates on Mars," said Moore.
Yahoo
13-06-2025
- Science
- Yahoo
Researchers make concerning discovery after investigating bays: 'They're a threat to everything'
Microplastics are slipping out of Texas bays and into the Gulf of Mexico, where they can do even more damage to the environment — and possibly to us. Researchers at the University of Texas at Austin recently found that microplastics in Texas bays, particularly Matagorda Bay, are not accumulating in sediments as expected. Instead, they are being transported into the Gulf of Mexico. The study, published in Environmental Science & Technology, analyzed 122 sediment samples from Matagorda Bay, East Matagorda Bay, and San Antonio Bay. Findings showed relatively low concentrations of microplastics in the samples — only tens to hundreds of particles per kilogram of sediment, which is hundreds to thousands of times less than similar bayside environments around the world. This data was entirely unexpected, according to the researchers — especially with a plastic pellet factory directly on Matagorda Bay. The researchers attribute the findings to shallow depths in the respective bays, along with windy conditions and frequent hurricanes, which prevent microplastics from settling. And if these microplastics don't settle, they get swept into the Gulf — which sends these tiny particles of plastic on an even more destructive journey. As the researchers outlined in the study, once in the Gulf of Mexico, these microplastics absorb environmental chemicals and accumulate in marine life. This can pose risks to the broader ecosystem and human health, as these microplastics enter the food and water supply. "It's good that the bay is not a microplastic dump or hotspot," study co-author Cornel Olariu, a research associate professor in the Jackson School's Department of Earth and Planetary Sciences, said in a statement. "But the bad thing is they move around much easier than we thought … and they're a threat to everything up to us." According to the Stanford Report, about 10 to 40 million metric tons of microplastics are released into the environment each year. Microplastics never disappear from the environment, contaminating waterways, soil, air — everything. While scientists are still learning exactly how microplastics impact animals, people, and the planet, it's clear that these pervasive plastic particles cause long-term damage. A 2020 study found that humans inhale approximately 16.2 bits of microplastics every hour. That's the equivalent of a credit card per week. Harvard Medicine highlights that microplastic exposure is linked to a wide range of human health impacts, including reproductive issues, cancers, inflammation, lung and liver problems, hormone disruptions, and changes to the gut microbiome. Understanding how and where microplastics travel is key to effectively tackling their environmental impact. This particular study marks the first time researchers have examined the prevalence of microplastics in Texas bay sediments, providing crucial baseline data for further research. Do you worry about air pollution in and around your home? Yes — always Yes — often Yes — sometimes No — never Click your choice to see results and speak your mind. As a next step in the research, the authors are developing models to trace the pathways of Texas bay microplastics, hoping to see where they collect if not in the bays. In the meantime, there are global efforts to reduce plastic usage to help combat microplastic prevalence. But with the prevalence of plastic in our lives and our environment, completely avoiding microplastics is not only unlikely — it's impossible. Still, there are simple ways to reduce your exposure. Opt for clothing made from natural fibers, skip plastic food packaging when you can, and bring reusable bags instead of relying on single-use plastics. Since microplastics are also in the air we breathe, regular vacuuming and using a HEPA air purifier can help limit indoor exposure. Join our free newsletter for good news and useful tips, and don't miss this cool list of easy ways to help yourself while helping the planet.
Forbes
27-04-2025
- Science
- Forbes
How Earth's Mantle Played A Role In Shaping Human Evolution
A sculptor's rendering of the hominid Australopithecus afarensis that lived 3.2 million years ago in ... More Africa. An international team of researchers investigated how Earth's mantle activity created an uplift between what is now the Arabian Peninsula and Anatolia about 35 to 20 million years ago. The resulting land bridge enabled the early ancestors of animals such as giraffes, elephants, rhinoceroses, cheetahs, and even humans, to leave Africa, ending a 75-million-year-long isolation of the continent. "This study has relevance to the question of 'How did our planet change, in general? What are the connections between life and tectonics?'" says Thorsten Becker, a study co-author and professor at the Jackson School's Department of Earth and Planetary Sciences and Institute for Geophysics, University of Texas. The full story begins 70 to 60 million years ago, when a slab of rock sliding into Earth's mantle melted, creating a plume that reached the surface some 30 million years later. The mantle plume pushing upwards, coupled with the collision of tectonic plates between Africa and Asia, created an uplift that contributed to closing the ancient Tethys Sea, splitting it into what is now the Mediterranean and Arabian Seas, and created a landmass that bridged Asia and Africa for the first time. In a similar way Iceland is today above sea level because it sits atop a mantle plume and between two tectonic plates. The study's lead author Eivind Straume analyzed the wide-ranging consequences of this geologic activity while he was a postdoctoral fellow at the Jackson School. He says the appearance of the land bridge and evolution of early hominids go hand in hand. "The shallow seaway closed several million years before it otherwise likely would have due to these specific processes—mantle convection and corresponding changes in dynamic topography," explains Straume, who is now a postdoctoral fellow at the Norwegian Research Center and The Bjerknes Center for Climate Research. "Without the plume, you could argue that the continental collision would have been different." Without the mantle plume, Africa and Asia may have remained isolated for much longer, and the animals that made their way into and out of Africa, including our ancestors, could have been much different. Several million years before the land bridge had completely closed, the primate ancestors of humans came to Africa from Asia. While those primates ended up going extinct in Asia, their lineages diversified in Africa. Then when the land bridge fully emerged, these primates re-colonized Asia and Europe. This uplift also had significant impacts on ocean circulation and Earth's climate. Without the Tethys Sea and oceanic currents redistributing energy to the north, the Indian Ocean got warmer and eastern Africa became more arid. Researchers believe this event was a final trigger in making the Sahara a desert, maybe even driving early hominids out of Africa as they followed the rain some 10 to 7 million years ago. The warmer ocean also enhanced evaporation and monsoon activity making southeast Asia wetter. This paper brings together existing research spanning plate tectonics, mantle convection, topography and paleogeography, evolutionary anthropology, mammal evolution, climate evolution, and ocean circulation, among other topics, to tell a cohesive story of the wide-ranging effects of these mantle dynamics. The study, "Collision, mantle convection and Tethyan closure in the Eastern Mediterranean," was published in the journal Nature Reviews Earth & Environment. Additional material and interviews provided by University of Texas at Austin.
