Vieira R.P.,University of Aveiro |
Vieira R.P.,UK National Oceanography Center |
Raposo I.P.,New University of Lisbon |
Sobral P.,New University of Lisbon |
And 3 more authors.
Journal of Sea Research | Year: 2014
Studies concerning marine litter have received great attention over the last several years by the scientific community mainly due to their ecological and economic impacts in marine ecosystems, from coastal waters to the deep ocean seafloor. The distribution, type and abundance of marine litter in Ormonde and Gettysburg, the two seamounts of Gorringe Bank, were analyzed from photo and video imagery obtained during ROV-based surveys carried out at 60-3015m depths during the E/V Nautilus cruise NA017. Located approximately 125nm southwest of Portugal, Gorringe Bank lays at the crossroad between the Atlantic and the Mediterranean and is therefore characterized by an intense maritime traffic and fishing activities. The high frequency of lost or discarded fishing gear, such as cables, longlines and nets, observed on Gorringe Bank suggests an origin mostly from fishing activities, with a clear turnover in the type of litter (mostly metal, glass and to a much lesser extent, plastic) with increasing depth. Litter was more abundant at the summit of Gorringe Bank (ca. 4items·km-1), decreasing to less than 1item·km-1 at the flanks and to ca. 2items·km-1 at greater depths. Nevertheless, litter abundance appeared to be lower than in continental margin areas. The results presented herein are a contribution to support further actions for the conservation of vulnerable habitats on Gorringe Bank so that they can continue contributing to fishery productivity in the surrounding region. © 2014 Elsevier B.V. Source
Talas E.,Dokuz Eylul University |
Duman M.,Dokuz Eylul University |
Kucuksezgin F.,Dokuz Eylul University |
Brennan M.L.,University of Rhode Island |
Raineault N.A.,Ocean Exploration Trust
Marine Pollution Bulletin | Year: 2015
Investigations carried out on surface sediments collected from the Anaximander mud volcanoes in the Eastern Mediterranean Sea to determine sedimentary and geochemical properties. The sediment grain size distribution and geochemical contents were determined by grain size analysis, organic carbon, carbonate contents and element analysis. The results of element contents were compared to background levels of Earth's crust. The factors that affect element distribution in sediments were calculated by the nine push core samples taken from the surface of mud volcanoes by the E/V Nautilus. The grain size of the samples varies from sand to sandy silt. Enrichment and Contamination factor analysis showed that these analyses can also be used to evaluate of deep sea environmental and source parameters. It is concluded that the biological and cold seep effects are the main drivers of surface sediment characteristics from the Anaximander mud volcanoes. © 2015 Elsevier Ltd. Source
Kelly J.T.,University of Rhode Island |
Carey S.,University of Rhode Island |
Pistolesi M.,University of Pisa |
Rosi M.,University of Pisa |
And 3 more authors.
Bulletin of Volcanology | Year: 2014
On October 17, 1891, a submarine eruption started at Foerstner volcano located within the Pantelleria Rift of the Strait of Sicily (Italy). Activity occurred for a period of 1 week from an eruptive vent located 4 km northwest of the island of Pantelleria at a water depth of 250 m. The eruption produced lava balloons that discharged gas at the surface and eventually sank to the seafloor. Remotely operated vehicle (ROV) video footage and high-resolution multi-beam mapping of the Foerstner vent site were used to create a geologic map of the AD 1891 deposits and conduct the first detailed study of the source area associated with this unusual type of submarine volcanism. The main Foerstner vent consists of two overlapping circular mounds with a total volume of 6.3 × 105 m3 and relief of 60 m. It is dominantly constructed of clastic scoriaceous deposits with some interbedded pillow lavas. Petrographic and geochemical analyses of Foerstner samples by X-ray fluorescence and inductively coupled plasma mass spectrometry reveal that the majority of the deposits are vesicular, hypocrystalline basanite scoria that display porphyritic, hyaloophitic, and vitrophyric textures. An intact lava balloon recovered from the seafloor consists of a large interior gas cavity surrounded by a thin lava shell comprising two distinct layers: a thin, oxidized, quenched crust surrounding the exterior of the balloon and a dark gray, tachylite layer lying beneath it. Ostwald ripening is proposed to be the dominant bubble growth mechanism of four representative Foerstner scoria samples as inferred by vesicle size distributions. Characterization of the diversity of deposit facies observed at Foerstner in conjunction with quantitative rock texture analysis indicates that submarine Strombolian-like activity is the most likely mechanism for the formation of lava balloons. The deposit facies observed at the main Foerstner vent are very similar to those produced by other known submarine Strombolian eruptions (short pillow flow lobes, large scoriaceous clasts, spatter-like vent facies). Balloons were likely formed from the rapid cooling of extremely vesicular magma fragments as a result of a gas-rich frothy magma source. The exterior of these fragments hyperquenched forming a vesicular glassy shell that acted as an insulating layer preventing magmatic gas in its interior from escaping and thus allowing flotation as densities reached less than 1,000 kg/m3. We believe that lava balloons are a common eruptive product, as the conditions required to generate these products are likely to be present in a variety of submarine volcanic environments. Additionally, the facies relationships observed at Foerstner may be used as a paleoenvironmental indicator for modern and ancient basaltic shallow submarine eruptions because of the relatively narrow depth range over which they likely occur (200-400 m). © 2014 Springer-Verlag Berlin Heidelberg. Source
A purple squid with eyes so googly it could easily be mistaken for a character in the movie "Finding Nemo" was recently spotted by scientists off the coast of Southern California. The so-called stubby squid (Rossia pacifica) is a species of bobtail squid native to the northern Pacific Ocean. These adorable sea creatures can be found in waters from Japan to Southern California, and typically dwell along the ocean floor, at depths of around 984 feet (300 meters), though they have been spotted as deep as 4,260 feet (1,300 m), according to the Monterey Bay Aquarium Research Institute (MBARI). The stubby squid's giant eyes, that "look painted on," delighted the scientists aboard the Exploration Vessel (E/V) Nautilus. In a live stream of the Nautlius' undersea explorations, one researcher said the googly-eyed squid looks "like some little kid dropped their toy." [Photos: See the World's Cutest Sea Creatures] "On that watch it happened to be a lot of geology folks or ecology folks, so a lot of the commentary was of course more like 'What is this thing, it's so cute!' and sometimes we have less of that when we see rocks," Samantha Wishnak, a science communication fellow aboard the E/V Nautilus, told Live Science. The scientists on watch during the squid sighting also initially misidentified the stubby squid as a cuttlefish, which the squid is closely related to. Wishnak said the E/V Nautilus team was able to rule out cuttlefish, as the species is not found in the eastern Pacific Ocean. With a few other ideas for what the species might be, the researchers on board collaborated with scientists ashore and at the University of California, Santa Barbara, and MBARI, to identify the stubby squid. Stubby squids are nocturnal hunters, so Wishnak said it was exciting to see the animal in its "somewhat natural behavior" rather than hidden in the sea floor. "They actually have this pretty awesome superpower, they can turn on a little sticky mucus jacket over their body and sort of collect bits of sand or pebbles or whatever they're burrowing into and make a really nice camouflage jacket," Wishnak said. "When they go to ambush something and prey on something, they're able to sort of turn off that mucus jacket." Other stubby squid sightings by divers have resulted in the same "deer in the headlights" kind of reaction, Wishnak said. The animals are used to being in darker waters, camouflaged from view. "I think what we encountered was a squid who was not expecting to see us in any way," Wishnak said. The E/V Nautilus is currently on a four-month expedition to explore the eastern Pacific Ocean. Next, the ship will move from the coast of Southern California to the San Francisco Bay. The vessel's mission is to explore the oceans and seek out the unknown, and is operated by the Ocean Exploration Trust, a nonprofit organization founded by oceanographer Robert Ballard. Recent discoveries on this expedition have included a mysterious purple sea orb and a sighting of the world's largest bony fish, the Mola mola. Copyright 2016 LiveScience, a Purch company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.
News Article | August 22, 2016
A team of scientists and technicians scanning the rocky ocean floor off Southern California couldn't contain their excitement when they spotted a bright-purple, googly-eyed stubby squid. They let out a collective "whoa" on video posted on the Exploration Vessel Nautilus' Facebook page as a camera on a remote-operated vehicle came across the iridescent cephalopod with giant round eyes. Then the jokes started. "He has weird eyes!" said one enthusiastic observer. "Get close! Get close!" urges another. One suggested it resembled a child's dropped toy, and another said the creature's eyes appeared to be painted on. "It looks so fake," says one member of the Nautilus' team. The creature looks like a cross between a squid and an octopus but is closely related to a cuttlefish, according to the Nautilus Live website. The find could be more than just bemusing. "In addition to the googly-eyed cuteness, there is one thing biologically interesting about this observation," said cephalopod expert Michael Vecchione of the Smithsonian Institution. The creature could be a new species, he wrote in an email to the expedition. It was spotted at nearly 3,000 feet deep, which is unusual, but not unheard of. But, on top of that, the stubby squid didn't have chromatophores, cells that allow it to change color, as members of its species do, Vecchione said. The question can't be answered because this particular stubby squid remains deep in the ocean, out of scientists' reach. The Nautilus team is part of a four-month Ocean Exploration Trust expedition to map underwater fault zones from Canada to California and understand ecosystems around them. The team spends hours scanning the barren ocean-scape, "then to come across something adorable like that — it's a real treat," Exploration Vessel Nautilus spokeswoman Susan Poulton said. Content Item Type: NewsSummary: A team of scientists and technicians scanning the rocky ocean floor off Southern California couldn't contain their excitement when they spotted a bright-purple, googly-eyed stubby squid. Featured Image: Contributed Author: By Alina Hartounian, Associated PressTopics: BiologyMeta Keywords: Exploration Vessel Nautilus, stubby squid, googly-eyed stubby squid, Nautilus Live website, particular stubby squid, Vessel Nautilus spokeswoman, expert Michael Vecchione, rocky ocean floor, four-month Ocean Exploration, underwater fault zones, Nautilus team, iridescent cephalopod, giant round eyes, weird eyes, Facebook page, remote-operated vehicle, Southern California, enthusiastic observer, googly-eyed cuteness, barren ocean-scape, Trust expedition, Susan Poulton, Smithsonian Institution, new species, real treat, creature, scientists, cuttlefish, excitement, octopus, technicians, jokes, member, observation, child, cross, ecosystems, camera, thing, feet, email, Canada, toy, chromatophores, colorExclusive: