Articles tagged with Sediment
New research reveals that salmon stocks varied greatly on centuries-long time cycles, with fluctuations lasting up to 200 years. The study found that natural variations in salmon abundance were as large as those due to human harvests, and that some regions showed different changes over time.
A recent University of Pennsylvania study published in Geology has challenged the long-held assumption that mountains play a significant role in regulating the Earth's climate. The research found that mountains contribute only a small amount of sediment to the world's oceans, and instead, gently sloping land areas are major contributors.
GEOLOGY articles reveal high-resolution images of Mercury's surface, further study of giant gypsum crystals in Naica Cave, and the provenance of North Atlantic ice-rafted debris. The publication also covers various geophysical studies, including the impact of the Galápagos hotspot on the East Pacific Rise.
A detailed analysis of Bonaire sediments suggests a 3,300-year-old tsunami changed the coastal ecosystem and sedimentation patterns. The study reveals overwash deposits consistent with a tsunami event, highlighting the long-term ecological significance of this single catastrophic event.
Rivers erode at an estimated 80 billion metric tons yearly, with 20 billion ending up in ocean water via rivers. Researcher Panos Diplas studies river mechanics to improve erosion process understanding and develop measures to control scour around bridge foundations.
Researchers at University of Massachusetts Amherst used biomarkers from human feces to establish the first human presence, arrival of grazing animals, and population dynamics in a landscape. The method provides a strong human signal with excellent chronological control, offering valuable insights into past environmental changes.
Scientists have found metabolically active bacteria in the brine of an Antarctic lake sealed under ice for over 2,800 years. The discovery provides new boundary conditions on life's limits and suggests that chemical reactions between the brine and underlying sediment generate energy for microbes.
A 450 million-year-old study reveals that an ancient hurricane belt existed in North America, affecting areas now known as New York State and the eastern seaboard. The research team mapped the position of the Ordovician Equator and adjacent tropical zones using fossil distribution and sediments.
A team of University of Pennsylvania geologists observed how sediment was deposited in the Mississippi Delta during the 2011 flood. They found that diverting water into the Atchafalaya River Basin built up sediment in wetland areas, whereas the Mississippi River plume had a more focused and less sediment-rich effect.
The Geological Society of America's Geosphere journal has added four special issues exploring the Sierra Nevada, Colorado River system, Laurentia, and the deep sea. New research reveals that Basin and Range volcanism was triggered by extensional tectonics, while Cenozoic erosion in southwestern North America was linked to surface uplif...
A new radiocarbon dating method enables precise calibration of past ages, improving climate change understanding. The method uses seasonal layered deposits in lake sediments to date older objects up to 52.8 kyr BP.
Researchers extracted cores from Japan's Lake Suigetsu, containing organic material that provides a direct record of atmospheric carbon, extending the radiocarbon dating record by over 40,000 years. This discovery enables scientists to pinpoint more accurately the timing of events such as Neanderthal extinction and modern human migration.
A new series of radiocarbon measurements from Japan's Lake Suigetsu provides a more precise and accurate dating method, especially for older objects. The record stretches back 52,800 years, offering improved resolution and confidence in radiocarbon dating.
Eberli's research on carbonate sediments and rocks has led to a revolutionary new model of platform development, revealing the internal architecture of Great Bahama Bank. The CSL Center for Carbonate Research he directs has made significant breakthroughs in understanding sedimentologic processes, aiding the petroleum industry.
A new study reveals that summers on the Norwegian archipelago of Svalbard are warmer than any other time in the last 1,800 years, with temperatures exceeding even the warmest periods during the Medieval Warm Period. This finding casts doubt on skeptics who argue that current warming is also natural.
A new study in Nature Geoscience reveals that the high-elevation flat surfaces of Norway's landscape are geologically young due to extensive glacial erosion. The research contradicts previous views and suggests a complete re-interpretation of Scandinavia's tectonic history.
A British team will penetrate and sample an ancient buried lake beneath three kilometers of ice in Antarctica. The team aims to reveal secrets about the Earth's past climate and discover life forms that may exist in subglacial Lake Ellsworth.
Scientists discovered two closely timed extinctions, one triggered by massive volcanic eruptions and another by an asteroid impact. The eruptions, which occurred 300,000 to 200,000 years before the asteroid hit, warmed the planet and killed marine life.
Researchers reconstruct 9,000-year record of delta's growth and find evidence of human impact on the entire Black Sea basin. The team finds that human deforestation and agriculture led to increased nutrient availability in the sea.
A team of researchers recovered sediment cores from the Pacific Ocean, revealing fluctuations in the carbonate compensation depth over millions of years. The findings suggest that climate development and carbon cycle interactions were more complex than previously thought.
A study by University of Rhode Island oceanographers and colleagues found drastically lower values for total biomass in marine sediments, reducing the estimated mass of all life on Earth by about one-third. The researchers collected sediment cores from open-ocean areas to obtain more accurate data.
A recent study by a German-US science team estimates that there is about 4 billion tons of carbon stored in subseafloor microbes, reducing the total amount of carbon stored in living organisms by about one third. This new finding challenges previous estimates based on drill cores taken in nutrient-rich areas.
A statewide analysis of Minnesota's freshwater bodies reveals widespread presence of personal care product antimicrobial ingredients triclosan and triclocarban. These chemicals persist for decades and contaminate human blood, urine, and breast milk.
A University of Michigan study found that tiny, freeloading clams form strong commensal relationships with larger hosts in soft-bottom habitats, allowing them to access previously unavailable habitats and thrive. This adaptation is associated with the evolution of megadiverse marine biodiversity.
A new study has discovered that Middle Reef, part of Australia's Great Barrier Reef, has grown more rapidly than other reefs in areas with lower levels of sediment stress. The reef thrives in water with high levels of sediment, which had previously been believed to be detrimental to growth.
Researchers found striking similarities between large Martian polygons and deep-sea polygons on Earth, suggesting a common origin. The team believes the Martian polygons were formed in a thick, wet, and weak layer of fine-grained sediments similar to those on Earth, supporting the idea of ancient oceans on Mars.
Researchers used tree ring data from the US Pacific Northwest and oxygen isotope analysis of lake sediments to clarify ancient climate regimes. The study suggests that drought patterns in the American West may have varied across different regions, with some areas experiencing wetter winters than expected.
A new Geosphere study uses virtual fieldwork to analyze terrain data from the 2010 Haiti earthquake, revealing evidence of active faulting and ancient surface rupture. The research also explores the provenance of sandstones in the Colton Formation and the interactions between the Seattle and Saddle Mountain faults.
Researchers have extracted a sediment core from Lake El'gygytgyn in Siberia, revealing temperatures previously thought impossible for the Arctic Circle. The findings suggest a correlation between warm periods in the Arctic and large melting events in Antarctica, indicating previously unknown interactions between the Polar Regions.
A new study reveals intense warm intervals in the Arctic over the past 2.8 million years, corresponding closely with times when parts of Antarctica were ice-free and also warm. The findings suggest strong inter-hemispheric climate connectivity and imply that the polar regions are more vulnerable to change than previously thought.
Scientists discovered that summer temperatures along the Antarctic coast were 20 degrees Fahrenheit warmer during the middle Miocene epoch, supporting substantial vegetation including stunted trees. This warming coincided with increased carbon dioxide levels and associated climate change.
Researchers have discovered that Mars' interior contains more water than previously thought, with implications for the planet's geological history. Additionally, a study of ancient stromatolites suggests that reef-building may have occurred earlier than previously believed, challenging current models of ecosystem development.
The study found that microbial eukaryote communities shifted from diverse nematode-dominated communities to an almost exclusively fungal community post-spill. Fungal taxa found post-spill are suspected to utilize hydrocarbons and thrive in hostile, polluted conditions.
Researchers found that about 12-5 million years ago climate was decoupled from atmospheric carbon dioxide concentrations. The climate of modern times more readily responds to changing carbon dioxide levels.
Researchers analyzed sedimentary and geochemical records from Rantin Lake to reconstruct past water-level changes and understand the timing and magnitude of prehistoric climate events. The study found that rapid climate change events occurred during the Holocene, with a notable 'megadrought' in the early period.
Researchers are analyzing lake cores for pollen, charcoal, and organisms to understand past biotic changes over 500,000 years. They aim to improve models predicting how life will adapt to today's environmental pressures and inform state planning on climate change.
Researchers used gravity and seismic geophysical methods to study the San Juan volcanic field in Colorado, revealing new constraints on its development. In Alaska, subducting plate geology was studied during three great earthquake ruptures, providing insights into tsunamis and future earthquake hazards.
New research from Aachen University suggests the Possidi peninsula in northern Greece is at risk of significant tsunami waves due to its proximity to earthquake-prone areas. The study also highlights the need for updated tsunami hazard calculations, particularly in densely populated and tourist regions.
A small marine worm can survive on poisonous carbon monoxide and hydrogen sulphide thanks to symbiotic bacteria that use these compounds to produce food for the worm. The worm has lost its entire digestive system over millions of years of evolution, relying solely on its symbionts for nutrition.
A team of scientists developed a new method to calculate the pace of life in deep sediments, using amino acid signatures to determine microorganism activity. They found that metabolism occurs at a much slower rate in the deep seabed compared to other ecosystems.
Researchers explore the geology of Mars, including widespread weathered glass, global aqueous history, and volcanic activity. Studies also examine the impact of human activities on river discharge, crustal anatexis, and electrical conductivity in the Yellowstone hotspot.
A University of Delaware oceanographer found trace amounts of radioactive iodine in the Delaware River, providing a new way to study substance travel through rivers to the ocean. The contaminant enters waterways via wastewater treatment systems and has a half-life of eight days.
A new study reveals that the Earth's early atmosphere periodically transitioned between a hydrocarbon-rich state and a haze-free environment due to microbial activity. This 'see-sawing' phenomenon had a profound impact on the climate system, with evidence suggesting a significant role in regulating atmospheric oxygen levels.
A new study reveals that the Indian monsoon has undergone significant changes over the last few millennia, from a steady humid monsoon to extended periods of drought. The research provides insights into the impact of the monsoon on past cultures and could help model future monsoons.
Researchers used a microbial lipid proxy to identify ancient droughts and alkaline soils on the Tibetan Plateau, associated with significant uplift nine million years ago. The study suggests that abrupt uplifts can cause enhanced aridity in central Asia.
Researchers have made significant discoveries about the New Madrid Seismic Zone, including its kinematics and potential for stepover structures. Additionally, studies on landslide prediction, gas domes in soft sediments, and regional moisture balance control offer new perspectives on geological phenomena.
The study reveals four distinct age distributions in basin sediments, tracing stages of basin formation and reflecting long-term secular variation. These findings shed light on the dynamic interplay of orogenic, erosional, and sediment-transport systems that shaped the region's geology.
A new study published in GSA BULLETIN suggests that linear dunes may have formed through erosion rather than deposition. The research found evidence of erosional origin similar to yardangs in China's Qaidam Basin, which could provide insights into the formation of linear dunes on other planets, such as Saturn's moon Titan.
Researchers examine evidence for a non-synchronous global event during the end-Permian mass extinction, and study how weak faults form through chemical reactions. They also propose a revised model of geomorphic response to climate change based on observations in Israel.
A study of Enol lake sediments reveals significant environmental changes throughout the last 13,500 years, including climatic differences amongst previously thought 'stable' periods. The research highlights human impact on the environment, particularly pasture and deforestation.
Researchers investigate giant submarine landslides using subsurface data to understand their form and origin. The study also sheds light on the tectonic history of the Eastern Cordillera and provides new insights into the formation of mountains along the Atlantic margin of northeastern Brazil.
A natural substance extracted from Moringa oleifera seeds can purify water by binding to sediment and killing microbes. The process uses functionalized sand, providing a simple, locally sustainable way to produce storable drinking water.
A team of four British engineers has successfully paved the way to explore an ancient lake buried beneath 3 km of Antarctic ice. The Lake Ellsworth Programme aims to yield new knowledge about the evolution of life on Earth and other planets, while extracting vital clues about the Earth's past climate.
The article discusses the discovery of missing mid-Cenozoic sediments in the Lomonosov Ridge drilling, the variation in the Intertropical Convergence Zone's (ITCZ) position with global climate changes, and the decoupling of taxonomic and ecological severities of major mass extinctions. The ITCZ's position was more southward than today ...
A comprehensive study of 36 lakes in the USA, Canada, Greenland, and Svalbard reveals that biologically active nitrogen from human sources can be traced back to the end of the 19th century. The rate of change has accelerated over the past 60 years, coinciding with the commercialization of artificial fertilizer production.
Researchers discovered plant bedding with insecticidal properties at a 77,000-year-old South African rock shelter. The bedding, made from sedges and rushes, was used to repel mosquitoes and other insects.
A new study projects a bleak future for San Francisco Bay's tidal marshes under high-end sea-level rise scenarios, with up to 93% of the bay's tidal marshes potentially lost. However, the study also highlights the importance of restoration efforts and sediment management in preserving these vital ecosystems.
Researchers from Princeton University reject the prevailing theory that a single large meteorite caused the mass extinction event at the end of the Cretaceous period. Instead, they link the extinction to massive volcanic eruptions in western India known as the Deccan Traps, which were 3 times larger than France.
Researchers found that organic carbon resides in the Ganges-Brahmaputra system for 500-17,000 years, making it a significant source of terrestrial biospheric carbon to the ocean. The relatively long carbon residence time poses big implications for the global carbon cycle.
Researchers are testing a new device that can measure contaminants with unprecedented precision, accuracy and sensitivity at Superfund sites. The device will evaluate the health effects of five specific compounds on two species of marine organisms.