Latest Sedimentology Stories
Scientists at TU Delft have successfully matched a layer of sediment from the dunes near Heemskerk to a severe storm flood that occurred in either 1775 or 1776. This type of information helps us gain more insight into past storm floods and predict future surges more accurately. The scientists’ findings have been published in the online edition of the scientific magazine Geology, and will be on the cover of the paper edition of November. Historic knowledge Our historic knowledge about...
Something's up with the weather in Namibia, say geoscientists Kyle Nichols of Skidmore College in Saratoga Springs, N.Y., and Paul Bierman of the University of Vermont in Burlington, Vt. Nichols and Bierman should know. They're just back from the western mountains and coastal plain of this sparsely populated African country. Usually, western Namibia is a dusty place where the stream beds are sand and the "lakes" are nothing more than flats of dried mud. Not now. This year, rivers...
Although the dune ecosystem is unusual, fragile and is protected by the "habitats" directive of the network Natura 2000, its conservation is very vulnerable to the proliferation of car parks, nearby buildings and inadequate boardwalks installed for protection or beach access.Researchers at the University of Seville (UoS) have published a study in the Journal of Coastal Research of human impact on the natural dunes at two sites in the Gulf of Cádiz, specifically in the protected...
The massive subduction zone earthquake in Japan caused a significant level of soil "liquefaction" that has surprised researchers with its widespread severity, a new analysis shows.The findings also raise questions about whether existing building codes and engineering technologies are adequately accounting for this phenomenon in other vulnerable locations, which in the U.S. include Portland, Ore., parts of the Willamette Valley and other areas of Oregon, Washington and California.A preliminary...
HOUSTON, April 11, 2011 /PRNewswire/ -- Texas Rare Earth Resources Corp (OTCQB: TRER) announced today it has begun a stream sediment sampling program at its Round Top Mountain rare earth-beryllium-uranium project in Hudspeth County, Texas which also includes niobium, tantalum and gallium. The objective is to determine if the geochemical signatures from the stream sediments can be used to identify areas of higher grade in the massive rhyolite. To date, a total of fourteen first order...
The sand along the south-western coastal rim of Norway has drifted for more than 9000 calendar years. This was triggered by sea-level changes and human activities, new research has found.Researchers in countries such as Denmark, the Netherlands and Poland study sand drift, but most of them are focusing on sand dunes along the coastline, not on the plains further inland."Sand dunes are dynamic. For all we know, they may have been formed last year. But sand plaines are much older and in periods...
Drier conditions projected to result from climate change in the Southwest will likely reduce perennial vegetation cover and result in increased dust storm activity in the future, according to a new study by scientists with the U.S. Geological Survey and the University of California, Los Angeles. The research team examined climate, vegetation and soil measurements collected over a 20-year period in Arches and Canyonlands National Parks in southeastern Utah. Long-term data indicated that...
A group of researchers have studied the history of drought in the Pacific Northwest during the last 6,000 years, a time that spans the mid-Holocene geological epoch to the present. The goal of the research was to improve the understanding of drought history because the instrumental record of drought only goes back a few hundred years and at relatively few locations.Their work extended the drought history of the Pacific Northwest back much longer than the tree ring record, which provides...
Much of the Mississippi River's sediment load doesn't come from field runoff, according to work by scientists at the U.S. Department of Agriculture (USDA). Instead, the scientists with USDA's Agricultural Research Service (ARS) have confirmed that stream bank collapse and failure can be chief contributors to high sediment levels in the silty streams and rivers that flow into the Mississippi. ARS is USDA's chief intramural scientific research agency.The U.S. Environmental Protection Agency...
Research published today reveals the previously unidentified role that fish play in the production of sediments in the world's oceans, and specifically of the carbonate sediments that contain critical records of changes in ocean chemistry and climate shifts in the geological past.The discovery, made by a team of scientists from the UK and US, helps explain the origins of a key component of marine sediments "“ the fine-grained carbonates, the origins of which are often problematic to...
Latest Sedimentology Reference Libraries
A river delta is a landform that is created at the mouth of a river, where the river flows into an ocean, estuary, lake, sea, or reservoir. These deltas are built from the deposition of the sediment that is carried by the river as the flow exit’s the mouth of the river. Over a long period of time, this deposition constructs the distinctive geographic pattern of a river delta. The creation of a delta is made up of three core forms: the bottomset, topset, and foreset/frontset. Bottomset...
In geology, a conglomerate is a rock consisting of other stones that have been cemented together. Conglomerates are sedimentary rocks consisting of subangular clasts and are thus differentiated from breccias, which consist of angular clasts. Both conglomerates and breccias are characterized by clasts larger than sand (>2 mm). There are two varieties of conglomerate, defined by texture: paraconglomerates and orthoconglomerates. Paraconglomerates are one of two varieties of conglomerate...
