A European team of researchers has demonstrated that sediment is transported to the deep sea via canyons in the seabed. The sediment accumulates in the head of the submarine canyons. At the end of the canyons, mud avalanches disperse into the deep sea. Scientists from the Netherlands Institute for Sea Research (NIOZ) presented their findings at an international congress held from 7 to 10 April 2002.
With bottom landers, onboard the ship R.V. Pelagia, the researchers explored the Nazaré Canyon off the Portuguese coast. This is one of the largest submarine canyons in the world. The Canyon starts at the beach. At a distance of 150 kilometres from the coast it opens out into a deep-sea area, 5 km deep. Locally the canyon cuts more than one kilometre deep into the continental slope. In the floor of the canyon the researchers measured unusually high biochemical activity. The sediment is enriched in organic material, which can serve as food for the rich floor life in the canyon and the deep-sea area. However, the sediment is possibly mixed with chemical pollutants originating from human activity. In addition to this the water in the canyon was noticeably turbid. This indicates an elevated transport of sediment particles. The sediment accumulates rapidly in the canyon. As a result of this the floor becomes unstable. The researchers demonstrated that the accumulated sediment runs off the slope as submarine mud avalanches into the deep-sea area. This happens at intervals of several decades to several centuries. With the rapid growth of the world population, the use of the continental margin (the transition area between the mainland and the open ocean) is quickly increasing. As a result of this marine ecosystems are being subjected to greater pressure. Ecosystems close to the mainland are comparatively well studied. However, the edges of the continental shelf and the continental slope have for a long time received comparatively little attention.
Michel Philippens | alphagalileo
Predicting unpredictability: Information theory offers new way to read ice cores
07.12.2016 | Santa Fe Institute
Sea ice hit record lows in November
07.12.2016 | University of Colorado at Boulder
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine