Sentences with phrase «seabed sediment»

Waters within a 20 - kilometer zone are still off - limits, and high levels of contamination have been found in seabed sediment and fish tested in the area.

A comprehensive new study looking at layered seabed sediment up and down the Northwest Coast has raised the odds of a great 8.0 - magnitude earthquake occurring by 2060 to nearly 4 in 10, according to the news site of the journal Nature.

[Update, Aug. 4, 2015 James Hansen has posted a detailed response to my comment on the Atmospheric Chemistry and Physics Discussion site questioning his paper's interpretations of beached boulders and seabed sediment formations as evidence of Eemian «superstorms.»]

More zoobenthos means more carbon being taken from the air and sequestered in seabed sediments.

The 78 - author paper, published Sunday in Nature Geoscience, used a variety of indirect indicators of temperature, from tree rings to pollen grains, to build on other work charting temperature shifts since the end of the last ice age — including the recent Marcott et al paper, explored here, which used seabed sediments to chart 11,000 years of temperatures.

Methane hydrate in ocean seabed sediments is a potential source of methane (CH4) to the atmosphere, where CH4 has potential to act as a powerful greenhouse gas.

Any methane released from under retreating ice sheets is more likely to find its way into the atmosphere than methane released from deep - sea methane hydrates, because the methane - consuming seabed sediments and the overlying sea water are absent in Antarctica.

Buried deep in seabed sediments off east Africa, scientists have uncovered a 24 - million - year record of vegetation trends in the region where humans evolved.

Not exact matches

Approximately 90 % of excavated seabed would be returned to the ocean floor along with tailings, creating a sediment plume approximately 1000 square kilometres in size.

Sander Houben of Utrecht University in the Netherlands and colleagues studied fossilised dinoflagellates — a type of plankton — in sediment cores from the Antarctic seabed to find out how these changes affected marine life.

Confirmation arrived in February this year, when an international team extracted 34 sediment cores from three sites on the seabed, revealing a fossilised coral reef that reaches 110 metres into the sea floor.

The mat had previously covered the seabed like a coating of plastic wrap, leaving the underlying sediments largely anoxic and off limits to animals.

Will it form sediment that gets buried beneath the seabed and eventually turns into plastic «oil» or «coal»?

In addition to a marine biologist's typical tools — water samplers to measure salinity and temperature, plankton nets — the team's toolbox will hold cameras, coring systems to collect seafloor sediment, and hydroacoustic equipment to map the topography of the now - exposed seabed.

This boundary can make or break a territorial claim over seabed resources but is often masked by thick sediment layers or other confounding features.

The study is the first to give a global overview of all current plans to mine the seabed, in both national and international waters, and looks at the potential impacts including physical destruction of seabed habitats, creation of large underwater plumes of sediment and the effects of chemical, noise and light pollution arising from mining operations.

An analysis of sediment from 17 seabed sites — from European estuaries to the Great Barrier Reef in Australia and the deep Atlantic Ocean — found that the bathyal region of the Rockall Trough has more species than any other area so far measured.

in the sediments below the seabed as well as by chemical transformation of organic matter at greater burial depths.

When the zoobenthos die, their bodies are eventually buried in the sediment of the seabed, sequestering carbon in the process.

Photo b shows an Antarctic shelf playing host to multiple zoobenthos, while photo d shows the skeletons of dead zoobenthos collecting on the seabed, a precursor to their carbon being buried in the sediment.

Re # 92 The carbonate compensation depth (the depth below which calcium carbonate dissolves) is shallow in polar waters, so calcium carbonate sediments are virtually absent on the arctic seabed.

The authors used two types of data from cores in sediments at the seabed — so - called «proxy data».

Large amounts of methane are produced in anaerobic conditions by bacterial activity in the sediments below the seabed as well as by chemical transformation of organic matter at greater burial depths.

''... worked with two sediment cores they extracted from the seabed of the eastern Norwegian Sea, developing a 1000 - year proxy temperature record «based on measurements of δ18O in Neogloboquadrina pachyderma, a planktonic foraminifer that calcifies at relatively shallow depths within the Atlantic waters of the eastern Norwegian Sea during late summer,» which they compared with the temporal histories of various proxies of concomitant solar activity... This work revealed, as the seven scientists describe it, that «the lowest isotope values (highest temperatures) of the last millennium are seen ~ 1100 - 1300 A.D., during the Medieval Climate Anomaly, and again after ~ 1950 A.D.» In between these two warm intervals, of course, were the colder temperatures of the Little Ice Age, when oscillatory thermal minima occurred at the times of the Dalton, Maunder, Sporer and Wolf solar minima, such that the δ18O proxy record of near - surface water temperature was found to be «robustly and near - synchronously correlated with various proxies of solar variability spanning the last millennium,» with decade - to century - scale temperature variability of 1 to 2 °C magnitude.»

Analysis of carbon isotopes in seabed samples from 14 offshore sites indicated that about 13 % of the carbon released by permafrost erosion ends up sequestered in nearshore sediments.

The basalts on land are relatively shallow, but those at sea are covered not only by water, but hundreds or thousands of feet of sediment, and appear to extend far below the seabed.

For example, Best (2006) speculated that increased organic sediments sent down rivers due to deforestation, factory farming, etc., once buried in the seabed, will be converted to methane by bacteria, perhaps seriously adding to greenhouse gas emissions.