scholarly journals Reconstruction of bedform dynamics controlled by supercritical flow in the channel–lobe transition zone of a deep‐water delta (Sant Llorenç del Munt, north‐east Spain, Eocene)

Sedimentology ◽  
2020 ◽  
Author(s):  
George Postma ◽  
Jörg Lang ◽  
David C. Hoyal ◽  
Juan J. Fedele ◽  
Timothy Demko ◽  
...  
Keyword(s):  
Transition Zone ◽  
Deep Water ◽  
Supercritical Flow ◽  
North East

scholarly journals Marine late Saalian to Eemian environments and climatic variability in the Danish shelf area

2000 ◽  
Vol 79 (2-3) ◽  
pp. 335-343 ◽  
Author(s):  
Marit-Solveig Seidenkrantz ◽  
Karen Luise Knudsen ◽  
Peter Kristensen
Keyword(s):  
Climate Variability ◽  
Shallow Water ◽  
Oxygen Isotope ◽  
Deep Water ◽  
Climatic Variability ◽  
Shelf Area ◽  
North East ◽  
The North ◽  
Mis 5E

AbstractThe marine Eemian (marine oxygen-isotope substage 5e: MIS 5e) is represented by shallow-water deposits in southern and western Denmark, while relatively deep-water environments occurred to the north and north-east, where complete interglacial successions seem to be present. We present an overview of the marine Eemian deposits in Denmark, and discuss in more detail indications of climate variability, both for the late Saalian and within the Eemian.

scholarly journals Deep-water channel-lobe transition zone dynamics: Processes and depositional architecture, an example from the Karoo Basin, South Africa

2018 ◽  
Vol 130 (9-10) ◽  
pp. 1723-1746 ◽  
Author(s):  
Hannah L. Brooks ◽  
David M. Hodgson ◽  
Rufus L. Brunt ◽  
Jeff Peakall ◽  
Menno Hofstra ◽  
...  
Keyword(s):  
South Africa ◽  
Transition Zone ◽  
Deep Water ◽  
Water Channel ◽  
Karoo Basin ◽  
Depositional Architecture

Reproductive patterns in two deep-water solitary corals from the north-east Atlantic—Flabellum alabastrumandF. angulare(Cnidaria: Anthozoa: Scleractinia)

2010 ◽  
Vol 91 (3) ◽  
pp. 669-675 ◽  
Author(s):  
Rhian G. Waller ◽  
Paul A. Tyler
Keyword(s):  
Sex Ratio ◽  
Deep Water ◽  
Oocyte Size ◽  
East Atlantic ◽  
Broadcast Spawning ◽  
Reproductive Patterns ◽  
Size Dependent ◽  
North East ◽  
The North ◽  
Rockall Trough

Gametogenesis and reproductive periodicity of the solitary scleractiniansFlabellum alabastrum(from the Rockall Trough) andF. angulare(from the Porcupine Seabight) were investigated. Samples were collected between depths from 1370 to 2190 m forF. alabastrumand 2412 to 2467 m forF. angulare. Both species showed gonochorism with a 1:1 sex-ratio and broadcast spawning of gametes is inferred from the lack of brooded planulae. Oocyte sizes were large in both species (925 μm inF. alabastrumand 1015 μm inF. angulare), suggesting lecithotrophic larval development. Fecundity and periodicity of oocyte development differed between the two species.Flabellum alabastrumproduced a maximum of 2800 oocytes per polyp quasi-continuously, whereas the deeper speciesF. angulareproduced a maximum of 550 oocytes per polyp either seasonally or periodically. Both species showed size-dependent fecundity. The data show a decrease in oocyte size and fecundity with depth, in concordance with other deep-water scleractinian species.

Ophlitaspongia and Ophlitaspongia papilla reinstated, and a new species of Ophlitaspongia described (Porifera: Demospongiae: Microcionidae)

1999 ◽  
Vol 79 (4) ◽  
pp. 609-620 ◽  
Author(s):  
C.M. Howson ◽  
S.J. Chambers
Keyword(s):  
New Species ◽  
North Atlantic ◽  
Deep Water ◽  
The Other ◽  
East Atlantic ◽  
Halichondria Panicea ◽  
North East ◽  
The North ◽  
The North Atlantic ◽  
A New Species

A new species of Ophlitaspongia (Porifera: Microcionidae) from wave-exposed sublittoral rock in the north-east Atlantic is described and compared to the two other species recorded from the genus in the north-east Atlantic. The species known as Ophlitaspongia seriata is considered to be a junior synonym of Halichondria panicea. Consequently, the name O. papilla has been reinstated. The other recorded species O. basifixa, is from deep water. Ophlitaspongia basifixa has characters which differentiate it from Ophlitaspongia sp. nov. The genus Ophlitaspongia has been separated from related genera and reinstated for species in the North Atlantic.

Molecular barcoding of north-east Atlantic deep-water sharks: species identification and application to fisheries management and conservation

2008 ◽  
Vol 59 (3) ◽  
pp. 214 ◽  
Author(s):  
Teresa Moura ◽  
Mónica C. Silva ◽  
Ivone Figueiredo ◽  
Ana Neves ◽  
Pablo Durán Muñoz ◽  
...  
Keyword(s):  
Deep Water ◽  
Objective Assessment ◽  
Dna Barcode ◽  
Coi Gene ◽  
Shark Species ◽  
Identification Problems ◽  
East Atlantic ◽  
Molecular Barcoding ◽  
North East ◽  
The North

Two genera of elasmobranchii, Centrophorus and Centroscymnus, include species that represent the highest landings of deep-water sharks caught by fishing fleets operating in the north-east Atlantic. There are morphology-based identification problems among and within genera, and landings of processed shark products further prevent an objective assessment of these species. The present study is the first attempt to test the suitability of using a DNA barcode approach to discriminate accurately among the four most important commercial deep-water shark species: Centrophorus squamosus, Centrophorus granulosus, Centroscymnus coelolepis and, recently discovered in Portuguese ports, Centroscymnus owstoni. Sequence analyses of the mitochondrial DNA cytochrome c oxidase subunit I (COI) gene revealed low levels of haplotypic and genetic diversities. Higher levels of inter-specific relative to intra-specific divergences allowed discrimination among species, which form reciprocally monophyletic clades. Inclusion of published COI sequences from other species within the same genera revealed haplotype sharing among species, which calls into question the current taxonomy and accuracy of fisheries data available. Amplification of the COI gene coupled with MboI restriction digests was found to be a fast and inexpensive strategy to resolve within genera identification problems. Molecular barcoding constitutes a critical tool for the assessment and implementation of urgent management policies for this group of species.

Effects of deep-sea bottom longlining on the Hatton Bank fish communities and benthic ecosystem, north-east Atlantic

2010 ◽  
Vol 91 (4) ◽  
pp. 939-952 ◽  
Author(s):  
P. Durán Muñoz ◽  
F.J. Murillo ◽  
M. Sayago-Gil ◽  
A. Serrano ◽  
M. Laporta ◽  
...  
Keyword(s):  
Deep Water ◽  
Deep Sea ◽  
Cold Water ◽  
Fish Communities ◽  
East Atlantic ◽  
North East ◽  
Sea Bottom ◽  
Rocky Outcrop ◽  
Area North ◽  
By Catch

The effects of deep-sea bottom longlining on fish communities and the benthic ecosystem, as well as the interactions between fishing and seabirds, were studied based on data collected from a joint collaboration between the Spanish Institute of Oceanography and a longliner, carried out on the Hatton Bank area (north-east Atlantic) in 2008. A total of 38 longline sets were distributed mainly along the rugged bottom of the rocky outcrop at depths ranging from 750 to 1500 m. Deep-water sharks and lotids were predominant in the catches contributing respectively 80.4% and 13.1% in terms of weight. Deep-water sharks were predominant in the discards. By-catch of cold-water corals and small glass sponges occurred along the western flank of the Hatton Bank, while large hexactinellids were found along the eastern flank. Longlines fished the adult fraction of vulnerable deep-water sharks and lotids. High catches per unit effort values for these species were obtained in coral areas. A combination of seabird-scaring streamer lines and other measures of preventing seabird by-catch were used. Only one fulmar was captured and it survived. Data on distribution of marine litter and derelict deep-sea gillnets are also presented.

scholarly journals First tracking of the oceanic spawning migrations of Australasian short-finned eels (Anguilla australis)

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Wayne M. Koster ◽  
Kim Aarestrup ◽  
Kim Birnie-Gauvin ◽  
Ben Church ◽  
David Dawson ◽  
...  
Keyword(s):  
Deep Water ◽  
Marine Mammals ◽  
Euphotic Zone ◽  
Life Time ◽  
Marine Predators ◽  
North East ◽  
The North ◽  
Anguilla Australis ◽  
Mesopelagic Zone ◽  
Diel Vertical Migrations

AbstractAnguillid eel populations have declined dramatically over the last 50 years in many regions of the world, and numerous species are now under threat. A critical life-history phase is migration from freshwater to distant oceans, culminating in a single life-time spawning event. For many anguillids, especially those in the southern hemisphere, mystery still shrouds their oceanic spawning migrations. We investigated the oceanic spawning migrations of the Australasian short-finned eel (Anguilla australis) using pop-up satellite archival tags. Eels were collected from river estuaries (38° S, 142° E) in south-eastern temperate Australia. In 2019, 16 eels were tracked for up to about 5 months, ~ 2620 km from release, and as far north as the tropical Coral Sea (22° S, 155° E) off the north-east coast of Australia. Eels from southern Australia appeared to access deep water off the Australian coast via two main routes: (i) directly east via Bass Strait, or (ii) south-east around Tasmania, which is the shortest route to deep water. Tagged eels exhibited strong diel vertical migrations, alternating between the warm euphotic zone (~ 100–300 m, 15–20 °C) at night and the mesopelagic zone (~ 700–900 m, 6–8 °C) during the day. Marine predators, probably lamnid sharks, tuna, or marine mammals, ended many eel migrations (at least ~ 30%), largely before the eels had left the Australian continental shelf. The long and risky marine migrations of Australasian eels highlight the need for better information on the processes contributing to eel mortality throughout the life cycle, including the impacts of future changes to oceanic currents, predator abundance and direct anthropogenic disturbances.

scholarly journals Stratigraphy and structural development of the Precambrian rocks in the area north-east of Disko Bugt, West Greenland

1967 ◽  
Vol 13 ◽  
pp. 1-28
Author(s):  
A Escher ◽  
M Burri
Keyword(s):  
Transition Zone ◽  
Greenschist Facies ◽  
Amphibolite Facies ◽  
Structural Development ◽  
West Greenland ◽  
Precambrian Rocks ◽  
The Third ◽  
North East ◽  
Area North

The Precambrian rocks in the area north-east of Disko Bugt can be divided into a lower gneiss group and an upper supracrustal group. The lower part of the supracrustal group consists of quartzites, amphibolites and garnet-staurolite schists, while the upper part is mainly semipelitic schist. The gneisses were affected by three successive phases of deformation, while in the supracrustals only the two latest phases of folding can be recognized. Evidence is given in support of the idea that the supracrustals were deposited on a gneiss basement after the first phase of folding, the basement being later reactivated mainly during the third and last deformation. Two main tectonic compLexes can be distinguished in the area mapped: a southern complex characterized by a predominarit ENE direction of the fold axes and a northern complex in which the main fold axes are strongly curved around a central gneiss dorne. The transition zone between the southern and northern complex is marked by the presence of severaL important faults and mylonites. The gneiss dorne is flanked in its northern part by a thick granite sheet. The dorne structure appears to have been forrned by a combination of diapiric movements and the interference between two successive deformations. The gneisses and lower supracrustals recrystallized under amphibolite facies conditions, while greenschist facies conditions prevaiLed during the recrystallisation of the upper supracrustals.

scholarly journals Evaluation of indigenous land races of deep-water paddy of North East India for nutraceutical value

2021 ◽  
pp. 125-127
Author(s):  
KANDARPA KALITA
Keyword(s):  
Deep Water ◽  
Weather Condition ◽  
Red Rice ◽  
Ethnic Communities ◽  
African Countries ◽  
Land Races ◽  
North East India ◽  
North East ◽  
The North

Deep water paddy is a nature’s marvel for many ethnic communities living in flood prone river basins of some Asian and African countries. In recent times there is resurgence in interest on local land races in view of alarming depletion of agro-biodiversity and the urgency to preserve them. In Assam, the north eastern state of India, deep water paddy is being cultivated since time immemorial by several ethnic communities living in the Brahmaputra river basin. Although not properly enumerated, it is known that more than 70 land races of Bao Dhanexists. Moreover, recent works have revealed that contrary to general perception deep water paddy are rich in nutritional and nutraceutical values with 9% to 13% protein. Further interest on deep water paddy got a boost with the report that land races with red kernel (red rice) are rich in dietary antioxidant anthocyanin and study showed that they have impressive anti-oxidative activity in vitro. Deep water paddy or floating paddy popularly referred to as Bao dhan in Assam, represent a unique crop capable of withstanding diverse stress and man’s ingenuity to co-exist with hostile nature and weather condition. Owing to their antioxidant capacity and the associated health benefits, anthocyanins have gained increased attention in recent years, hence the study was initiated.

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