Articles tagged with Sediment
A 250-kilometer-diameter basin in the Falkland Islands exhibits traits of a large impact crater, including decreased gravity strength and increased magnetic field strength. The structure is estimated to be approximately 270-250 million years old, potentially correlating with the largest mass extinction event.
A new Stanford study found that microbes sometimes fail to break down all plant and animal matter, leaving behind buried organic carbon. This preserved carbon can seep into nearby oxygen-rich waterways, where it's consumed by microbes, contributing to greenhouse gas production.
Scientists have discovered DNA from ancient humans in cave sediments lacking skeletal remains. The technique used has identified Neandertal and Denisovan DNA sequences, providing valuable insights into human evolutionary history.
A new technique developed by an international team has enabled the extraction of DNA from hominids preserved in sediments, allowing researchers to determine which species occupied a site and its diet. The method analyzed fragments of mitochondrial DNA from 85 samples of Pleistocene sediments from eight Eurasian caves.
Scientists at Max-Planck Institute develop new method to retrieve hominin DNA from cave sediments, revealing genetic affiliations of ancient humans. The discovery sheds light on human evolution, allowing researchers to uncover the genetic history of extinct species like Neandertals and Denisovans.
A recent landslide in Washington killed 43 people, prompting researchers to investigate the disaster. The study found that the landslide's height and potential energy were primary factors, but also revealed the importance of sediment type, precipitation, and erosion.
Wind-driven expansion of marsh ponds on the Mississippi River Delta is a major factor in land loss, with 17% of loss attributed to pond expansion. The study suggests diverting sediment to marsh ponds can halt expansion and reverse the trend of land loss.
A study found that a gentoo penguin colony in Antarctica was almost completely wiped out after three large volcanic eruptions over the past 7,000 years. The eruptions from Deception Island volcano had a devastating impact on the population, causing ash fall and burying chicks.
Scientists reconstruct past climate records from Tibetan Plateau sediment samples, revealing a greater than 6 million year earlier onset of 100,000 year climate cycles. The findings suggest that Antarctic ice sheet fluctuations in the late Miocene exerted dominant control on these cycles.
A recent study precisely dated the India-Asia continental collision at 59±1 million years ago, based on sedimentary record analysis. The collision resulted in the formation of the Himalayan Mountains and the rise of the Tibetan Plateau, with significant climatic and environmental changes.
Scientists uncover regional warming in Europe causing cooling and increased snowfall in East Asia during the Younger Dryas period, highlighting the complex interplay of teleconnections. The study provides new insights into the climate changes of the northern hemisphere at the end of the last glacial phase.
A study by Colorado State University researchers found that an extreme flooding event in 2013 eroded over 500,000 cubic meters of sediment, equivalent to 115 years of weathering products. The flood also discharged large amounts of organic carbon and wood into reservoirs, affecting water storage capacity.
A recent study by the University of the Basque Country found that not all metals in sediments directly affect human health, but only a fraction can be incorporated into the body. The researchers simulated metal release in the gastrointestinal tract and found that urban waste water contributes to bioaccessible metals.
Researchers found that Chaoborus spp larvae absorb excess methane bubbles to inflate their air sacs, enabling them to reach the surface. This mechanism not only saves energy but also exacerbates greenhouse gas emissions. Improving water quality is crucial in mitigating this effect.
Researchers found that rivers in regions with high erosion rates transport more sediment, which adjusts the channel geometry to moderate flows. This challenges the threshold channel model, which predicts a specific grain size range for gravel-bedded rivers.
The Nile Delta, a vital breadbasket for Egypt, is at risk of serious water scarcity due to human activities and the upcoming completion of Ethiopia's Grand Ethiopian Renaissance Dam. The delta's soil-rich areas are being eroded by Mediterranean coastal currents and experiencing compaction, leading to subsidence and sea-level rise.
Researchers analyzed Lake Towuti sediment using visible-near infrared spectroscopy and found distinct variations in clay mineralogy over the past 40,000 years. This technique can help reconstruct ancient Martian climate history.
Researchers found that a 80,000-year ice age caused by volcanic eruptions led to the loss of 95% of marine species during the Permian-Triassic boundary. The study challenges previous theories attributing mass extinctions to warming temperatures.
Coral ecosystems in West Maui's northern reefs have declined by 20% due to sediment runoff, compromising corals' ability to photosynthesize. Researchers found that cooperation among landowners results in more cost-efficient and ecologically effective outcomes than individual actions.
Research by Jeroen Ingels reveals that meiofauna, small organisms living in sediment, contribute to food production, nutrient cycling, and waste breakdown. These tiny creatures help regulate the Earth's system, impacting marine ecosystems and human life.
Research reveals large-scale thaw-induced slope disturbances and mobilization of primary glacial sediments, leading to cascading effects on fluvial, lacustrine, and coastal systems. The study's findings have major implications for predicting northern landscape change and downstream impacts.
Brown University researchers demonstrate the efficacy of using herbaceous plant specimens from the late 19th century to track changes in heavy metal concentrations over time. Despite challenges, including mercury contamination, they show significant reductions in lead concentrations and highlight broader trends in heavy metal accumulat...
A new USDA grant aims to determine if stream-bank legacy sediments are significant sources of nutrients to surface waters. The study will focus on understanding the fate of legacy sediments, their microbial community composition and nutrient transformation processes in aquatic ecosystems.
Researchers at Uppsala and Umeå University found that the molecular composition of sediment organic matter controls methylmercury formation. Organic compounds from phytoplankton are linked to high mercury methylation rates, while carbon compounds from the watershed do not have this effect.
A recent study published in PNAS reveals that Mars' primitive atmosphere had a low CO2 level, making it inhospitable for the formation of liquid water lakes. This finding contradicts previous assumptions and suggests that the planet's climate may have been colder than previously thought.
A new technique uses remote sensing to assess coastal salt marshes' potential to survive environmental challenges. The UVVR ratio is a good surrogate for labor-intensive field studies, tracking the main destructive processes in marshes.
Scientists have uncovered a continuous record of the Green Sahara period's rainfall patterns, revealing that the region was 10 times wetter than today. This discovery provides critical climate context for understanding human migration and lifestyle changes during this period.
The study estimates that about 3,000 tons of PHCZs lie in the sediment under lakes Michigan, Superior, and Huron, with Category 2 PHCZs likely from man-made sources. Most PHCZs, however, are believed to result from natural processes.
Physicist Tyrone Daulton reviews Younger Dryas sediments for nanodiamonds and finds none, contradicting the impact hypothesis. He attributes this to misidentification of similar carbon structures, such as graphene and graphane.
For the first time, boron has been identified on the surface of Mars, indicating potential for long-term habitable groundwater in the ancient past. The discovery was made using NASA's Curiosity rover's Chemistry and Camera instrument.
Scientists propose a novel plate tectonic scenario for the genesis of major Mesozoic oil fields. The model suggests that rapid continental movement and changes in latitude could have led to the emplacement of organic carbon at equatorial latitudes, eventually sealing it with sediments deposited at sub-tropical latitudes.
Researchers reconstructed the African dust plume over the last 23,000 years and observed a dramatic reduction in dust beginning around 11,000 years ago. This weakened plume may have allowed more sunlight to reach the ocean, increasing its temperature by 0.15 degrees Celsius, leading to an increase in monsoon rains over North Africa.
Research reveals that the grounding line of Pine Island Glacier retreated from a prominent seafloor ridge by 1945, with final ungrounding occurring in 1970. The team's findings suggest that ice-sheet retreat continued even when climate forcing weakened.
The Alps are steadily uplifting at a rate of 1-2 millimeters per year, with the majority of this movement attributed to the loss of the Last Glacial Maximum (LGM) ice cap. Researchers have found that 90% of today's uplift is due to the thawing of ice, rather than tectonic activity or erosion.
Researchers analyzed sediments from a Tanzanian peat bog to reconstruct the region's ecosystem over 1,200 years. The study found that forest biodiversity remains relatively stable despite human activity, but climate change poses a threat to its future.
A University of Southampton study reveals that tropical storms are a significant contributor to the decline of river deltas globally. The researchers used archived measurements to detect sediment concentration changes in the Mekong River delta, finding that one-third of the sediment is due to tropical cyclones.
Researchers found evidence of a comet strike in sediment from the Paleocene-Eocene Thermal Maximum (PETM), a rapid warming of the Earth caused by an accumulation of atmospheric carbon dioxide. The discovery provides insight into the sequence of events leading to global warming.
Research predicts an increase in water availability in the Blue Nile Basin of Ethiopia due to climate change, potentially allowing for two crops per year. However, increased sediment transport poses a challenge, highlighting the need for conservation practices and efficient irrigation development.
Researchers studied the distribution and characteristics of natural gas hydrates in fine-grained sediments from Shenhu area, South China Sea. They found that foraminifera shells played a crucial role in increasing porosity and hydrate accumulation.
A study by Ohio State University and The Nature Conservancy reveals that protecting Lake Erie's streams will require substantial conservation efforts, particularly in reducing phosphorus, nitrogen, and sediment runoff. The research uses computer modeling to gauge the impact of various conservation scenarios, highlighting the need for t...
Research in Japanese lakes reveals an increase in lead contamination since 1900, contradicting the global trend of declining lead emissions. The study suggests that industrialization in East Asia is a significant source of trans-boundary lead pollution affecting Japan.
A new technique pioneered by scientists at Plymouth University can unravel historic changes to Antarctic sea ice, as well as demonstrate past alterations to glaciers and ice shelves. The method builds on an existing technique that identified changes to Arctic sea ice, allowing for the recovery and analysis of IP25 lipids from sediments.
Researchers have found fossilized whale skeletons in the Ica Desert of Peru, providing insights into the Miocene whale feeding habits. The discovery also reveals exceptional microstructure preservation, allowing for the study of fossilized baleen bristles at a submillimetric scale.
A new study from Columbia University and MIT found that large-scale groundwater pumping is contaminating aquifers in Southeast Asia with high levels of arsenic, posing a significant risk to human health. The researchers discovered clear patterns of contamination that can help farmers and communities locate lower-risk sites for wells.
A new report by an international team led by a University of Arizona geoscientist shows that Lake Tanganyika's fishery productivity has been declining since the 19th century due to global warming. The lake's algae, which serves as a food source for fish, has also decreased in abundance.
Researchers found that calcareous sediments, not clay-rich sediments, are the most likely candidates for the first breakage of an earthquake. The study suggests that these sediments form a weak point in the rock sequence, leading to shallow earthquakes and tsunamis.
A new study reveals the exact timing of the modern monsoon pattern in the Maldives 12.9 million years ago, linking it to past climate changes and coral reefs. The analysis of sediment cores provides direct physical evidence of environmental conditions that sparked the monsoon system still affecting the Indian subcontinent today.
A new study of fossil fishes from Middle Triassic sediments on Lake Lugano finds that biological communities recovered within a few million years after the great mass extinction event. The research identifies two new species of ancient fish with distinct ecological niches, suggesting that ecosystems were already recovering.
Researchers measured oxygen content in ancient atmosphere trapped in halite (rock salt) and found it to be a key component in determining the origin and evolution of higher life forms. The discovery has applications beyond origins of life, including tracking atmospheric changes and finding economic metal deposits.
Researchers at University of Wollongong have discovered physical evidence of fire use by modern humans at Liang Bua site on Flores Island, narrowing the time gap between hobbit species and modern human arrival. The findings suggest that modern humans likely arrived in Southeast Asia and Australia around 50,000 years ago.
Researchers created a sediment Microbial Fuel Cell (sMFC) system that can remotely investigate the physiology and ecology of electrically active microbes in submerged field sites. The device's cathode depth affected microbial community composition and energy recovery from sediments.
Researchers found that an underwater site off the coast of Greece was actually a natural geological formation, not the ruins of a lost civilization. The site's unique structure was created by mineralization at hydrocarbon seeps, with microbes using methane as fuel to form a type of natural cement.
A recent study found that underwater grass beds at Susquehanna Flats can protect and maintain their own health despite harsh conditions. The beds exhibit a natural ability to reduce damage from extreme events through biophysical feedback processes.
Researchers found that chemical reactions between injected freshwater and fractured shale caused barium to leach directly from the rock. They also discovered a specific depth interval where barite grains were 'bitten' by pyrite, leading to barium mobilization in clay minerals.
TSU researchers developed an ecological method for cleaning lakes from oil, which reduces oil content in water by 35-40 times. The technology uses a flotation method to remove oil from both sediments and water without using chemicals.
A new framework proposes that rapid marsh bank sediment build-up does not equate to increased land loss resilience, according to researchers from LSU and Boston University. The study suggests that natural sediment recycling processes in marsh channels may be overestimated when vertical accretion rates are compared to sea-level rise.
A trio of new age-dating methods developed at Duke University can determine the age of oil and gas wastewater spills and identify their origins based on radium isotope variations. The methods verify that radium's decay products, including thorium and lead isotopes, can be used to detect the age and source of spills.
Scientists analyze sedimentary archives in Alberta Foreland Basin, revealing cyclic changes in sediment source areas consistent with magmatic flare-ups. In another study, researchers uncover pre-Cenozoic geologic history of the central and northern Tibetan Plateau, tying Wilson cycles to constructing the Tethyan orogenic system.
A Penn State geoscientist is joining the NASA Mars rover team to investigate whether environmental conditions on Mars were ever favorable for microbial life. He will analyze Martian rocks and compare them to Earth rocks to search for signs of life, including sulfur and organic matter.
Scientists have uncovered a wetland-like environment beneath the West Antarctic Ice Sheet, where Subglacial Lake Whillans is fed by melting ice and small amounts of seawater. The findings provide unique insights into the biogeochemistry and geophysics of subglacial lake systems, which are essential for understanding global sea-level rise.