Articles tagged with Sediment
Scientists analyzed ancient ocean sediments to reconstruct past CO2 levels, finding that elevated CO2 led to the early Eocene epoch's extreme warmth and subsequent cooling. The study provides insights into understanding ancient climate and predicting future climate change.
A study found that crayfish increase macroinvertebrate density in polluted streams. The presence of crayfish also reduces sediment settling, creating a more favorable habitat for these organisms. This research highlights the potential benefits of invasive species like crayfish in alleviating problems in impaired streams.
A study suggests that gas hydrates in sediments slowed down an ice stream in the Barents Sea during the last ice age. The sticky spots under the ice act like hook and loop fasteners, creating friction and lubrication that can stop or slow the flow of the ice stream.
Scientists discover sediment cores from Lomonosov Ridge, revealing a window into Arctic Ocean climate history. The cores show that the central Arctic was ice-free during summer, with sea surface temperatures reaching 4-9 degrees Celsius.
Rising river waters deliver a feast of carbon to hungry microbes, triggering increased activity that could naturally boost emissions. The study suggests a link between the mixing of surface water and groundwater, leading to a decline in dissolved organic carbon and an increase in inorganic carbon.
Researchers study coastal uplift and erosion in Northern California, discovering rivers cut down hillslopes, triggering landslides that balance uplift. Landslides also deliver resistant rocks to rivers, delaying erosion, with implications for landscape evolution and hazards like landslides.
A study of loess accumulation in the northeastern Iranian Golestan Province and south Tajikistan reveals widespread dust storms and a semi-arid climate during the early Pleistocene. The findings suggest that an arid environment developed in mid-latitude Asia, consistent with other regions experiencing aridification during this period.
Drumlin hills, shaped like upturned boats, are formed when sediment is streamlined 'islands' that are often bisected to form megaridges. The research suggests that drumlins and megaridges are part of a single family of landforms formed by erosion, with the data indicating they occur on hard rock.
New research reveals that human-driven carbon release rate is 10 times faster than any event since the age of dinosaurs. The study uses sediment cores and numerical simulations to extract rates of change, showing a maximum sustained carbon release rate of about one-tenth the current rate.
Researchers estimate human carbon release rate is about 10 times faster than any event in the past 66 million years, with potentially catastrophic consequences for future climate changes. The study also suggests that the effects of massive fossil fuel burning will have a much longer tail than previously thought.
Researchers reconstructed a 2,000-year record of precipitation changes in the eastern Pacific using sediments from Galapagos lakes, revealing long-term shifts in El Niño patterns. The study provides new insights into tropical climate dynamics and will help model future changes.
Researchers used Landsat satellite data to detect shipwrecks in sediment-laden coastal waters, finding plumes extending up to 4 kilometers downstream from shallow wreck sites. This new method could aid in locating uncharted shipwrecks, preserving historical and ecological significance.
A recent study by University of Massachusetts Amherst researchers suggests that the destruction of oyster reefs in New York Harbor led to a significant increase in storm-induced overwash deposition. The authors found that before European settlement, oyster beds absorbed wave energy, providing coastal protection.
Researchers investigate the formation of a tiny volcanic island near Nishinoshima volcano, Ogasawara Islands, Japan. The island's unique lava flows and internal pathways provide valuable insights into the geological processes that shape our planet.
A new device, IS2B, developed by Arizona State University researchers accurately measures chemical contamination in water and sediment. The tool assesses the bioavailability of hazardous chemicals, which is essential for understanding health risks from pollution.
Researchers are racing to understand and mitigate the degradation of major river deltas worldwide, primarily caused by human activities such as damming, groundwater extraction, and agriculture. The study highlights that more than two-thirds of the world's 33 major deltas are sinking at an alarming rate.
The interaction of water and magma can dramatically increase the explosivity of a volcanic eruption, producing billowing clouds that deposit tephra as fine-grained ash within 10 km of the vent area. The study of the 2008 Okmok eruption in Alaska provides insights into water-magma interactions and their impact on eruption parameters.
Researchers propose a new conceptual model for monogenetic eruptions, suggesting seismic crises occur before eruption and magmatic intrusions play a key role. This framework could improve forecasting of these events in populated areas, reducing economic and societal impact.
Researchers evaluated the performance of Riegl Z620i and LPM-800HA terrestrial laser scanners on characterizing natural surfaces. They established a procedure to test componential uncertainty budgets and demonstrated the relationship between reference network uncertainty and imaged surface repeatability.
Research from the University of Southampton found that man-made sounds can alter the behavior of seabed creatures, impacting nutrient recycling and carbon storage. Exposure to certain sounds can cause species to reduce irrigation and sediment turnover, leading to reduced oxygen levels and potentially affecting seabed productivity.
Researchers have identified a previously unknown massive volcanic eruption in the Caribbean Sea, which occurred 2.4 million years ago on Guadeloupe. The VEI-6 eruption is the largest documented event in the region since its discovery.
A new study reveals that human activities are the main cause of hypoxia in freshwaters worldwide, with 71 lakes showing significant changes since the mid-19th century. Aquatic rehabilitation programs have failed to restore lake ecosystems to their original well-oxygenated state.
A 140-meter long sediment core from the Caribbean Sea has uncovered evidence of a massive 2.4 million-year-old volcanic eruption, which was likely larger than any recorded event in the region. The discovery provides valuable insights into past volcanic activity and its potential impact on future eruptions.
A new study by Duke University researchers found that coastal marshes can adapt to rising sea levels through increased plant productivity and soil generation, reducing the extent of marsh loss. The 'CO2 fertilization effect' allows marshes to trap more sediment and create organic soil, which helps them keep pace with sea-level rise.
A team of scientists has discovered that strong medieval earthquakes in Nepal triggered massive debris flows that reshaped the landscape over a distance of more than 60 kilometers. The study used 14C radiocarbon dating to determine the timing of sediment deposits and found that they coincide with documented large earthquakes in the reg...
A new study shows that Greenland's glaciers are retreating twice as fast as in the past 9,500 years, highlighting their acute temperature sensitivity. The sediment cores from a glacier-fed lake provide the first continuous observation of glacier change in southeastern Greenland.
Studies by Dartmouth researchers found that mixing of sediments and microorganisms significantly impact methylmercury production, contradicting earlier assumptions about sediments as the primary source.
The study reveals that microbes in shallow layers of seasonal wetlands use digestible plant material for energy, releasing arsenic into underlying groundwater. However, under normal conditions, these microbes do not pose a significant threat to groundwater arsenic concentrations.
Researchers have discovered that climate-induced glaciation during ice ages can wear down mountains at a rate comparable to plate tectonics' ability to build them. Over a million-year period, erosion accelerated sharply due to global climate cooling, outpacing mountain building by 50-80 percent.
Erosion caused by glaciation during ice ages can wear down mountains faster than plate tectonics can build them, according to a new study. The research, conducted over more than a decade, revealed that erosion rates accelerated sharply about 1 million years ago when global climate cooling triggered stronger and more persistent ice ages.
Researchers measure mountain range material flow and find glacial erosion accelerates faster than tectonics can rebuild mountains. Climate fluctuations play a pivotal role in shaping Earth's landforms, with erosion rates outpacing tectonic inputs by up to 80%.
A groundbreaking international study has revealed that mountain ranges actively evolve with the Earth's climate, responding to changes in temperature and ice cover. The research found that erosion accelerated sharply during global cooling periods, wearing down mountains faster than plate tectonics can build them.
The diversity and number of foraminifera in Bellingham Bay and Bremerton areas have deteriorated significantly, despite a reduction in chemical pollutants. Researchers are investigating alternative environmental factors, including high acidity caused by decomposition of organic matter and industrial contaminants.
San Francisco State University researchers developed a new method to analyze river rocks, revealing the impact of climate on sediment size. The study found that larger sediment sizes are produced on steeper, colder mountains, controlling canyon formation.
A new study warns that wildfires may double soil erosion in some western US states by 2050, degrading water quality and affecting aquatic life. The increase in wildfires due to climate change is projected to cause at least a 100% increase in erosion in a quarter of western watersheds.
Researchers at the University of Washington found bubble plumes off the coast of Washington and Oregon, suggesting that warmer ocean temperatures are releasing frozen methane. This process could contribute to climate change by amplifying environmental changes already impacting local biology and fisheries.
Mangrove forests around the Indo-Pacific region are at risk of submersion due to sea-level rise. However, some areas such as east Africa and north-western Australia may be able to persist despite rising seas.
A new study has found that changes in the polar regions can significantly affect the ocean and climate on the opposite side of the world, far quicker than previously thought. The research linked ocean currents to climate conditions during the last ice age, revealing a tight connection between the two.
Researchers analyzed Yellow River sediment to reconstruct global climate and topography history. They found that the Loess Plateau acts as a sink for Yellow River material eroded from the Tibetan plateau, contradicting previous expectations.
Scientists have identified microbes that produce methylmercury, a highly toxic form of mercury, in environments such as coastal sediments, marshes, and rice paddies. The discovery builds on previous work and highlights the risk of increased methylmercury production due to climate change.
A new paper published in Science reveals that Mars had a more massive atmosphere billions of years ago and a wet climate, with long-lived lakes filling Gale Crater. The discovery contradicts existing climate models and sheds light on the planet's ancient past, similar to the resolution of Earth's continental drift puzzle.
New study on Karoo Basin finds no support for climate aridification, floral collapse, and tetrapod turnover as part of the extinction event. Multidisciplinary data indicate that terrestrial response occurred earlier than previously thought.
Researchers found that too-pure recycled water can pick up arsenic as it seeps underground, causing temporary spikes in levels. The water's lack of calcium and magnesium ions allows arsenic to be repelled from clay particles, entering the water instead.
A historic storm triggered widespread flooding in Colorado's Front Range, causing massive landslides and rapid debris flows that transported hundreds of years' worth of accumulated sediment. Researchers used high-resolution topographic maps to measure the effects of extreme weather on erosion rates.
Large earthquakes cause catastrophic landslides that can persist up to 20-fold after the earthquake, then gradually decrease over time. The magnitude of this response is linked to the size of the earthquake, with shaking-induced damage near Earth's surface and active healing processes playing a key role.
A three-year study reveals that contaminated sediments from Fukushima are resuspended by typhoons and transported to the Pacific Ocean. The research team tracked radiocesium levels in sediment samples along the continental shelf and slope, finding high concentrations of clay material characteristic of near-shore sediments.
Researchers used computed microtomography to investigate a well-preserved fossil arthropod from the famous Chengjiang Lagerstätte in China. The study revealed anatomical details previously hidden in the rock matrix, allowing for the identification of the species as Xandarella spectaculum.
Engineered nanoparticles from common products like paint and sunscreen can harm aquatic organisms when they settle in sediments. The review calls for further research into nanoparticle fate and toxicity in these ecosystems.
A new digital seafloor geologic map created using artificial intelligence reveals that deep ocean basins are more complex than previously thought. The map shows diatom accumulations on the seafloor are nearly entirely decoupled from diatom blooms in surface waters, highlighting a key link in the carbon cycle.
The study provides the first complete account of the Gorkha earthquake's physical process, revealing a contained rupture at depth. The findings suggest that while the earthquake did not cause widespread destruction, it increased stress on an adjacent portion of the fault, potentially leading to future earthquakes.
Researchers from MIT and WHOI have developed a simple way to predict a river delta's shape, influenced by its river's sediment flux and ocean waves' strength. The new metric can help engineers determine how engineered structures like dams and levees may affect the coastline of a river delta.
Researchers discovered novel enzymes in microorganisms called archaea that break down organic matter into carbon dioxide, with implications for climate change. The study found that an increase in ocean temperature accelerates this process, releasing more carbon dioxide and methane into the atmosphere.
A new study reveals that the Campi Flegrei caldera's caprock resembles ancient Roman concrete, with intertwining fibrous minerals contributing to its high strength. The findings help explain how the caldera has endured significant deformation without erupting.
A research team led by Professor Ronnie N. Glud will investigate how life exists at extreme depths and its impact on the global carbon cycle. The team will use underwater robots to collect samples and measure microbial activity in three deep-sea trenches.
AGU researchers explore the impact of the Sabah earthquake on sediment production and river systems in Malaysia, while also discussing improved predictions for Arctic sea ice extent. The findings highlight the urgent need to better understand and predict these natural phenomena.
Researchers found suspended sediment harms fish gills, reducing oxygen intake and triggering diseases. This study highlights the need for coastal developments to consider sediment's impact on reef ecosystems.
The concentrations of Dechlorane Plus were found to decrease with increasing distance from the plant, with anti-DP being the predominant isomer. The results suggest that DP production activities release DP to the environment around the plant.
Researchers from the Geological Society of America discovered intricate microbe-sediment systems in ancient rocks, suggesting thermophilic life forms existed at least 3.3 billion years ago. The findings indicate that these early life forms were deeply rooted in time and flourished in hydrothermal environments.
Researchers have found four enormous craters on the lake bed, measuring 80-160 meters in diameter and up to 60 meters deep. The craters are filled with a suspension of water and sediment, indicating that they are linked to karst systems and possibly triggered by earthquakes.
A team of scientists proposes using nuclear weapons fallout to mark the beginning of a new geological age, the Anthropocene. The proposal is based on the significant geochemical signatures left by human activities in sediments accumulating across the planet.