... Title : The History of Sedimentation and Abyssal Circulation on the ... Subject Categories : PHYSICAL AND DYNAMIC OCEANOGRAPHY GEOLOGY ...

... The remainder of the basin includes a small triangular abyssal plain known as the Oman Abyssal Plain, a long, narrow abyssal plain between the ...

Abyssal marine sediments cover a large proportion of the ocean floor, but linkages between their microbial community structure and redox stratification have remained poorly constrained. This study compares the downcore gradients in microbial community composition to porewater oxygen and nitrate concentration ...

... Accession Number : ADA086952. Title : Bottom Currents and Abyssal Sedimentation Processes South of Iceland. Descriptive Note : Doctoral thesis,. ...

A fundamental approach to erodibility of fine abyssal sediment must take into account the great complexity of forces acting on surface sediment particles exposed to bottom currents. The only general conclusion that can be drawn is that, for a given sedime...

One of the possibilities for the storage of high-level radioactive wastes consists in burying them into abyssal sediments, the sediments being supposed to barrier out radionuclides migration. The objective of the work was to estimate the efficiency of sed...

The mantle origin of abyssal peridotites and their alteration by hydrothermal solutions and seawater have been the object of intensive study in the scientific community in recent years. Abyssal peridotites from the American-Antarctic and southwest Indian ...

A study of more than 100 sediment cores from the Arctic Ocean reveals that turbidity current deposits comprise about 27 percent of the cored sediments in the northeast and southeast parts of the Canada Abyssal Plain. The most common sedimentary structures...

Within the Sohm Abyssal Plain sand and coarse silt are major constituents of bottom deposits. These coarse layers are interstratified with clay. High impedence contrasts at the water-sediment interface and at textural breaks within the sediment section fa...

... foraminifera in early Paleogene sediments of DSDP Hole 27-259, Perth Abyssal Plain off Western Australia, doi: ... ...

... foraminifera in early Paleogene sediments of DSDP Hole 27-259, Perth Abyssal Plain off Western Australia, doi: ... ...

... foraminifera in Lower Cretaceous sediments of DSDP Hole 27-261, Argo Abyssal Plain, northwest of West Australia, ... ...

This study provides for the first time data on the nematode community composition from the Weddell Sea Abyssal Plain. In addition, new data on the nematode communities from the Cape Verde Abyssal Plain and the Porcupine Abyssal Plain are provided. Three stations along an east west transect in ...

The present study represents the first quantitative investigation of deep-sea benthic infauna in Antarctica. Box cores and multicores were used to collect sediment from 12 stations across the slope and abyssal basin of the Weddell Sea and the slope off the South Sandwich Islands, including sites in the South Sandwich Trench (6300 m). The multicore was a ...

Diverse faunal groups inhabit deep-sea sediments over much of Earth's surface, but our understanding of how interannual-scale climate variation alters sediment community components and biogeochemical processes remains limited. The vast majority of deep-sea communities depend on a particulate organic carbon food ...

Diverse faunal groups inhabit deep-sea sediments over much of Earth's surface, but our understanding of how interannual-scale climate variation alters sediment community components and biogeochemical processes remains limited. The vast majority of deep-sea communities depend on a particulate organic carbon food ...

In 1992, two independent reports based on small-subunit rRNA gene (SSU rDNA) cloning revealed the presence of novel Archaea among marine bacterioplankton. Here, we report the presence of further novel Archaea SSU rDNA sequences recovered from the midgut contents of a deep-sea marine holothurian. Phylogenetic analyses show that these abyssal Archaea are a paraphyletic component ...

Recognizing the rapidly decreasing availability of disposal sites on land, in 1993 Congress directed the Department of Defense to assess the technical and scientific feasibility of isolating contaminated dredged material on the abyssal seafloor. The Naval Research Laboratory (NRL...

The geochemistry of a suite of box and 2m gravity cores from the Nares Abyssal Plain has been characterised by means of pore water analyses, XRF determination of major and trace element concentrations, mineralogy and exp 230 Thsub(excess) dating. The inte...

Little is known about the benthic communities of the Arctic Ocean's slope and abyssal plains. Here we report on benthic data collected from box cores along a transect from Alaska to the Barents Abyssal Plain during the Arctic Ocean Section of 1994. We determined: (1) density and biomass of the polychaetes, foraminifera and total ...

... and evolution. It is central to such basic contemporary issues as whether communities are structured by biological interactions ... ...

A study of marine sediments in three major environments of the north Pacific; the continental terrace (shelf and slope), abyssal plain (turbidite), and abyssal hill (pelagic). Laboratory values of the mass physical properties of the sediments (e.g., sound...

Eukaryotic microbial life at abyssal depths remains �uncharted territory� in eukaryotic microbiology. No phylogenetic surveys have focused on the largest benthic environment on this planet, the abyssal plains. Moreover, knowledge of the spatial patterns of deep-sea community structure is scanty, and what little is known originates ...

The Florida Escarpment near 26/sup 0/N was surveyed with Deep-Two, Seabeam, and GLORIA in the area where chemosynthetic communities were discovered via ALVIN in the abyssal Gulf of Mexico. Seabeam bathymetry and GLORIA images indicate that the escarpment is a generally straight cliff with average slopes of about 45/sup 0/ from 2,200 to more than 3,250 m. ...

Spheres from mid-Pacific abyssal clays (0 to 500,000 yrs old), formed from particles that completely

... PHYSICAL LAB. Personal Author(s) : Lonsdale,Peter F. Report Date : 28 JAN 1975. Pagination or Media Count : 22. Abstract ...

The main purpose of the cruise was to obtain samples of sediment and sediment pore waters for geochemical research. The primary objectives were: to sample the sediments in the 10 km x 10 km abyssal plain area centered on 31 deg 17 min N, 25 deg 24 min W (...

Some 20 stable elements were determined by neutron activation analysis in epibenthic organisms and sediments from the Cape Verde abyssal plain. The levels measured in two Plesiopenaeus sp. (shrimp) individuals and one Barathrites sp. (fish) individual are...

A deeply towed instrument package surveyed three sites in the southern part of the Panama Basin where fast bottom currents control abyssal sedimentation. On the central Carnegie Ridge a field of sand dunes at a depth of 2.7 km was remapped to determine th...

The Florida Escarpment near 26/degree/N was surveyed with Deep-Tow, Seabeam, and GLORIA in the area where chemosynthetic communities were discovered via ALVIN in the abyssal Gulf of Mexico. Seabeam bathymetry and GLORIA images indicate that the escarpment is a generally straight cliff with average slopes of about 45/degree/ from 2200 to more than 3250 m. ...

Profiles of dissolved and particulate carbonate in abyssal sediments have been calculated and the associated fluxes determined. The fractions of CaCO3 in accumulating sediments were then evaluated. The calculations considered: effect of depth on solubilit...

The late Quaternary terrigenous sediments of the continental margin and abyssal plains of the western equatorial Atlantic consist predominantly of hemipelagic silty clay rich in organic detritus with interbeds of redeposited silts and sands; deposition wa...

Displaced Antarctic diatoms at the sediment/water interface were studied in deep-sea cores taken from the Argentine Continental Slope and Rise as well as the abyssal floor. The object was to determine, if the distribution of these diatoms in the sediment ...

A first attempt is made to present the full picture of the accumulation of elements in abyssal ferromanganese nodules relative to ocean sediments based on original data and data from the literature obtained mostly in the past 5 to 6 years. Manganese in th...

Oct 1, 2005 ... communities of the deep Gulf of Mexico entitled "The Deepwater Program: ... abyssal plain of the central Gulf of Mexico through ...

Seismic stratigraphic evidence indicates that a major change in abyssal circulation occurred in the latest Eocene-earliest Oligocene of the North Atlantic. Reflector R4 reflects a change from weakly (Eocene) to vigorously circulating bottom water (early Oligocene). Sediment distribution studies indicate a northern source for this bottom water, probably ...

Understanding how pelagic sediment has been eroded, transported, and deposited is critical to evaluating pelagic sediment records for paleoceanography. We use digital seismic reflection data from an Integrated Ocean Drilling Program site survey (AMAT03) to investigate pelagic sedimentation across the eastern-central equatorial Pacific, ...

The finding of a considerable amount of turtle grass at abyssal depths off North Carolina and at bathyal depth off Florida suggests a continuing fall-out of sea grass as a source of organic enrichment for the deep-sea floor. Turtle grass does not grow in ...

Using an instrument package towed close to the sea floor (the MPL Deep Tow device), a 250 square km area of abyssal hills in the vicinity of 14 degrees N, 126 degrees W has been surveyed in detail. In general the sediment surface is smooth with maximum el...

Trench outer slopes are among the most dynamic regions in the world. As lithosphere approaches a subduction zone it first flexes up into an outer rise then down into the trench. The flexure of the lithosphere is most commonly modeled as an elastic process reflecting the age of the lithosphere, however large-scale inelastic deformation coupled to the weakening of the bending plate results in a ...

Eukaryotic microbial life at abyssal depths remains "uncharted territory" in eukaryotic microbiology. No phylogenetic surveys have focused on the largest benthic environment on this planet, the abyssal plains. Moreover, knowledge of the spatial patterns of deep-sea community structure is scanty, and what little is known originates ...

... Connelly. 1984. A multiple corer for taking virtually undisturbed samples from shelf, bathyal and abyssal sediments. Oceanologica Acta ... ...

Spheres from mid-Pacific abyssal clays (0 to 500,000 yrs old), formed from particles that completely melted and subsequently recrystallized as they separated from their meteoroid bodies, or containing relict grains of parent meteoroids that did not experi...

The oldest sediment yet sampled from the abyssal margins of South America, late Jurassic (or possibly very early Cretaceous) shallow-water, coarse-grained, calcareous sandstone containing palynomorphs and mollusk prisms, was recovered from a depth of 4400...

At the High Energy Boundary Layer Experiment (HEBBLE) site (4820 m depth in the western North Atlantic) periods of strong currents and sediment erosion alternate with periods of weak flow and massive deposition. We investigated the impact of this atypical...

Three sediment samples from the Gulf of Mexico abyssal plain were subjected to five representative handling and storage procedures before the pore water was expressed and analyzed for Na(+), K(+), Mg(2+), and Ca(2+). The observed alterations in major cati...

... 11 Abyssal Hills 12 Seamount or Seamount Province 13 Aseismic Oceanic Rise or Ridge (eg, Rio Grande Rise ... &.I 0- mo o o o o o o o o o o o z o o o ...

A study of a 60 x 150 km area at 60 /sup 0/W.24/sup 0/N at the eastern end of the Nares Abyssal Plain indicates that hydrothermal circulation is still active in the 80 m.y. B.P. oceanic crust. The 58 heat flow measurements made at five stations in the area have revealed (1) constant heat flow over the abyssal plain (56 mW m/sup -2/), (2) a cycle heat flow ...

Abyssal hills, which are pervasive landforms on the seafloor of the Earth's oceans, represent a potential tectonic record of the history of mid-ocean ridge spreading. However, the most detailed global maps of the seafloor, derived from the satellite altimetry-based gravity field, cannot be used to deterministically characterize such small-scale (<10 km) morphology. ...

This report presents a comprehensive overview of the deep sea benthic environment of the Gulf of Mexico from the continental slope to the abyssal plain. Interpretations of biological communities are based on the analysis of a series of deep sea macroinfau...

This report presents a comprehensive overview of the deep sea benthic environment of the Gulf of Mexico from the continental slope to the abyssal plain. Interpretations of biological communities are based on the analysis of a series of deep sea macroinfau...

The topics covered in this report include: geologic siting considerations for the disposal of radioactive wastes into submarine geologic formations; geologic assessment of the MPG-1 regions Central North Pacific; site mapping; geotechnical aspects of subsurface seabed disposal; heat transfer, thermal and fluid physics in the deep ocean sediments; mechanical response predictive ...

Studies of deep-sea biodiversity focus almost exclusively on geographic patterns of alpha-diversity. Few include the morphological or ecological properties of species that indicate their actual roles in community assembly. Here, we explore morphological disparity of shell architecture in gastropods from lower bathyal and abyssal environments of the western ...

A wide variety of deep-water depositional environments were examined across 12 sampling stations in the Southern Ocean and northern Weddell Sea, Antarctica in order to provide a depositional context for the benthic biodiversity studies of ANDEEP (Antarctic Benthic Deep-Sea Biodiversity: colonisation history and recent community patterns). Here we present a diverse dataset ...

The Late Jurassic was a time favorable for the deposition of black shale-type sediments in shallow environments as known from circum-North Atlantic basins, North Sea, and Himalayan Tethys regions. Locally these shales have excellent hydrocarbon source potential. The site of the Spiti shales in the Thakkola region of north-central Nepal provides the opportunity to study a ...

The ecological forces that drive community structure of deep-sea benthic communities are poorly understood, yet such communities rival in biological complexity those of coral reefs or rainforests. Using components of the recently concluded DGoMB project, local and regional-scale structure of benthic macrofaunal ...

A compilation of potential hydrocarbon trap types has been assembled for the Louisiana offshore, from coastal plain to abyssal plain. These potential traps are listed according to paleophysiographic provinces: coastal plain, shelf, shelf break, upper slope, middle slope, lower slope, and abyssal plain. Characteristics of each trap type are tabulated. The ...

The quantitative study of the distribution and taxonomic composition of recent living and dead (without plasma) benthic foraminifers revealed three foraminiferal assemblages in the bottom sediments of the Pacific Ocean at depths of 3350 to 4981 m. The assemblage dominated by the epibenthic Lagenammina difflugiformis, Reophax dentaliniformis, and Saccorhiza ramosa occupies the ...

This document summarizes the status of geoscience investigations in the two primary North Atlantic study locations Great Meteor East (GME) in the Madeira Abyssal Plain, and the Southern Nares Abyssal Plain (SNAP), and assesses the characteristics of these locations relative to the guidelines considered desirable and necessary for a potential subseabed ...

Produce 'living' sediments by inoculation of sterile sediments with Antarctic bacteria and diatoms that will support natural microbial communities. ...

Produce 'living' sediments by inoculation of sterile sediments with Antarctic bacteria and diatoms that will support natural microbial communities. ...

... An accurate and useful model will require coupling sediment-transport with hydrodynamic forcing and stratigraphy. The ...

Recognizing the rapidly decreasing availability of disposal sites on land, in 1993 Congress directed the Department of Defense to assess the technical and scientific feasibility of isolating contaminated dredged material on the abyssal seafloor. The Naval Research Laboratory (NRL) conducted and managed the assessment, which was funded during its first year by the Strategic ...

We mapped the occurrence of living and fossil deep-sea corals using R/V Atlantis, DSV Alvin, the autonomous vehicle ABE, and a towed camera system, and we collected these corals and their associated fauna at sites on the New England and Muir seamount chains in the northwest Atlantic. On cruise AT7-35 (May-June 2003; the Medusa Expedition), we used a nested mapping approach to span observational ...

To evaluate paleoceanographic conditions from chemical and physical records in pelagic sediments more accurately, it is imperative to understand how the sediment has been transported, deposited and eroded. To date, few researchers have studied how these processes have affected seafloor topography over time, and the works were limited to near surface data ...

During July-September 1986, about 700,000 km/sup 2/ of continental slope and abyssal plain of the Aleutian basin, Bering Sea, were insonified with GLORIA (Geological Long Range Inclined Asdic) side-scane sonar. A sonar mosaic displays prominent geomorphic features including the massive submarine canyons of the Beringian and the northern Aleutian Ridge slopes and shows ...

Near-surface sediments (0-45 mm depth interval) form the Iceland Basin (59�N, 21�W, 3070-m water depth) and Biscay Abyssal Plain (48�N, 17�W, 4105-m water depth) were sectioned at millimeter-scale resolution to assess alterations in key lipid biomarkers during early diagenesis. Inventories (?g cm-2 in the topmost 45 mm) of biomarkers from presumed ...

... Accession Number : AD0238069. Title : THE GEOMORPHOLOGY OF ABYSSAL PLAINS IN THE NORTHEAST PACIFIC OCEAN. ...

... Title : Effects of Biological Activity by Abyssal Benthic Macroinvertebrates on a Sedimentary Structure in the Venezuela Basin,. ...

... Title : CERTAIN REGIONAL PROPERTIES OF THE ABYSSAL STRUCTURE OF THE EARTH'S CRUST IN THE TERRITORY OF THE USSR IN THE ...

This report is the result of an examination of the feasibility of isolating contaminated dredged material on the abyssal seafloor. The focus is on the technical and environmental factors that constrain the considerations of feasibility. A thorough conceptual design of a dredging to abyssal deposition system is analyzed with regard to each subsystem and to ...

The sedimentary history and seismic structure of a deep-water turbidite basin in the Western North Atlantic Ocean has been investigated to understand further the evolution of abyssal plains. This study integrates analyses of sedimentary and seismic facies in order to examine the temporal and spatial patterns of sedimentation on the northern Hatteras ...

It is hypothesized that in the deep-sea, under psychrophilic, barophilic and oligotrophic conditions, microbial community of Central Indian Basin (CIB) sediments could be chemosynthetic. In the dark, at near ambient temperature, 4 � 2�C, 500 atm pressure, pelagic red clay could fix carbon at rates ranging from 100 to 500 nmol C g(-1) dry wt day(-1). ...

Species diversity, phylogenetic affiliations, and environmental occurrence patterns of thiosulfate-oxidizing marine bacteria were investigated by using new isolates from serially diluted continental slope and deep-sea abyssal plain sediments collected off the coast of New England and strains cultured previously from Galapagos hydrothermal vent samples. The ...

... Title : Flocculation, Optics and Turbulence in the Community Sediment Transport Model System: Application of OASIS Results. ...

... Title : Flocculation, Optics and Turbulence in the Community Sediment Transport Model System: Application of OASIS Results. ...

and used as evidence for their shallow-water origin. The importance of intensified carbon transport caused on the magnitude of carbon 302 #12;TURBIDITE-DRIVEN REDOX CHANGES Figure 1. Pore-water sulfate (open circles conditions in abyssal sediments. Pore-water sulfate and methane concentrations were used as indicators

Lower Miocene microfossils occur in basaltic glass in two dredge hauls from the crestal area of the Mid-Atlantic Ridge near 30 deg. N. From the ridge and adjoining abyssal hills 43 pre-Pleistocene cores were identified, including one Cretaceous and four E...

Respiration in the open ocean Paul A. del Giorgio* & Carlos M. Duarte * De�partment des sciences to biological respiration. Estimates of respiration are available for the top layers, the mesopelagic layer, and the abyssal waters and sediments of various ocean regions. Although the total open ocean respiration

On the basis of bathymetric an seismic data collected recently off the coast of Makran in the Gulf of Oman, it has been suggested that the folding of the sediments at the northern edge of the abyssal plain is taking place at the present time. The folding is thought to be the consequence of ongoing subduction of the Arabian plate beneath the Eurasian ...

Three nodules from a core taken north of Puerto Rico are composed chiefly of an x-ray amorphous, hydrated, iron-manganese oxide, with secondary goethite, and minor detrital silicates incorporated during growth of the nodules. No primary manganese mineral is apparent. The nodules are enriched in iron and depleted in manganese relative to Atlantic Ocean averages. The formation of these nodules ...

A geological and geophysical study of the Samoan Passage in the west equatorial Pacific (168-170 degrees W; 7-10 degrees S) was carried out in 1971, using underway seismic reflection profiles (3.5 kHz and sparker), bottom photographs, bottom current measu...

Seventeen piston cores up to 13 m long were recovered from representative acoustic and lithologic environments of the Hatteras and Nares Abyssal Plains in the western North Atlantic. Compressional-wave velocities (corrected to in situ conditions) and bulk physical properties measured on the cores are used to characterize the acoustic framework of these areas. For correlation ...

drifts along the Pacific continental slope of the Antarctic Peninsula were drilled as part of Leg 178 from the continental shelf of the drift deposits that were drilled during the cruise. Results. Magnetostratigraphy of sediment drifts on the continental rise of west Antarctica (ODP Leg 178, Sites 1095, 1096

... 2 - Community composition of the sandy marine sediments ... ECOSYSTEMS ... and Metabolic Activities of Benthic Near-Shore Microbial Communities ...

Discovery Cruise 185 was concerned primarily with an investigation of the numbers and biomass of benthic organisms at the European Community site at 48 50'N 16 30'W in the North Atlantic Ocean (depth c. 4850m). Studies covered a wide size range of organis...

The late stage of the North East Atlantic (NEA) spring bloom was investigated during June 2005 along a transect section from 45 to 66� N between 15 and 20� W in order to characterize the contribution of siliceous and calcareous phytoplankton groups and describe their distribution in relation to environmental factors. We measured several biogeochemical parameters such as nutrients, surface ...

The late stage of the North East Atlantic (NEA) spring bloom was investigated during June 2005 along a transect section from 45 to 66� N between 15 and 20� W in order to characterize the contribution of siliceous and calcareous phytoplankton groups and describe their distribution in relation to environmental factors. We measured several biogeochemical parameters such as nutrients, surface ...

We reconstructed the ventilation record of deep water at 2100 m depth in the mid-latitude western North Pacific over the past 25 kyr from radiocarbon measurements of coexisting planktic and benthic foraminiferal shells in sediment with a high sedimentation rate. The 14C data on fragile and robust planktic foraminiferal shells were concordant with each ...

This paper uses information contained in other papers in this issue of the AGSO Journal together with the scientific literature to produce a synthesis of the geological development of the outer continental margin of northwest Australia, and the adjacent plateaus and abyssal plains, with special emphasis on the northern Exmouth Plateau and Rowley Terrace. In the Palaeozoic, the ...

It has been estimated from heat flow measurements that at least 40% of the total hydrothermal heat lost from oceanic lithosphere is removed from 0.1-5 Ma abyssal hill terrain on mid-ocean ridge flanks. Despite the large magnitude of estimated hydrothermal heat loss from young abyssal hills, little is known about characteristics of hydrothermal vents and ...

Although heat flow studies suggest that ~70% of the hydrothermal heat loss in the oceans occurs in the abyssal hill terrain on the flanks of mid-ocean ridges, very few off-axis hydrothermal sites have been discovered. In May 2002, sedimentary blowout structures of probable hydrothermal origin were discovered along East Pacific Rise at 9� 27'N on an off-axis ...

Features evident on GLORIA sonographs from the Nares Abyssal Plain suggest a sediment dispersal pattern for turbidity currents that varies temporally and spatially, resulting in randomly distributed turbidite deposits in the distal abyssal plain east of 64/sup 0/W. Regional variations in backscatter intensities across the ...

We present the seafloor morphology and shallow seismic structure of the continental slope south-east of the Balearic promontory and of the adjacent Algero-Balearic abyssal plain from multibeam and chirp sonar data. The main purpose of this research was to identify the sediment pathways from the Balearic promontory to the Algero-Balearic deep basin from the ...

Meiobenthos (excluding foraminifers) from the South Sandwich Trench was studied in sediment samples collected by multiple core (MUC) or multiple grab (MG). Sampling stations were chosen along a depth transect that covered the continental slope and abyssal plain towards the trench (water depths from 747 to 6319 m). Total abundance and biomass of meiobenthos ...

The Ocean Drilling Program (ODP) has completed three expeditions bordering South America and is in the planning stages of a further expedition. The first cruise, Leg 110, drilled at six sites on a transect across the structural boundary between the overthrusting Barbados Ridge Complex and Atlantic abyssal plain (Caribbean/Atlantic Plate Boundary) in order to investigate ...

Three distinct carbonate deposits have been identified on the slope and adjacent sea floor of the Southwestern Florida platform: (1) reef talus, recognized by shape and location, found on the upper slope of the Yucatan Channel and also east of the Marquesas Keys; (2) hemipelagic sediments, with complex sigmoidoblique bed forms, filling the intervening gap between the channel ...

The sediments in the area affected by the runoff from the Columbia River were studied to determine the distribution of sediment types and the presence and amount of radioactivity in the sediments. The study of the dispersal processes and distributional patterns of the sediment and its radioactivity is in the ...

Effective diffusion coefficients for selected radionuclides have been measured in ocean floor sediments to provide data for the assessment of barrier effectiveness in subseabed repositories for nuclear waste. The sediments tested include illite-rich and smectite-rich red clays from the mid plate gyre region of the Pacific Ocean, reducing ...

Effective diffusion coefficients for selected radionuclides have been measured in ocean floor sediments to provide data for the assessment of barrier effectiveness in subseabed repositories for nuclear waste. The sediments tested include illite-rich and smectite-rich red clays from the mid-plate gyre region of the Pacific Ocean, reducing ...

... Accession Number : ADP006836. Title : Relationship Between Sediment Pollution and Macrobenthic Communities in Hiroshima Bay, Japan,. ...

... design, implement, and monitor MNR and ... ENGINEERING, *SEDIMENTS, *CONTAMINATION, *WATER POLLUTION ABATEMENT, COMMUNITIES ...

Most probable number counts of bacteria in sediment samples from the Sediment ... Characterisation of Cyanobacterial Associates of Plant Communities of ...

... frequency of fish disease, sediment toxicity ... edible tissue of fish and shellfish ... COMMUNITIES, CONTAMINATION, DISEASES, DISPOSAL, DREDGED ...

The impact of bioturbation in Lake Baikal sediments, particularly on rhythmic layering and mixing, was assessed by studying the actual vertical distribution of benthic animals in continuous accumulation zones selected by seismic survey (Vydrino Shoulder, Posolskoe Bank, Continent Ridge). To assess the influence of the bioturbation, animals were extracted from short cores and ...

Recent changes of carbonate deposition were traced in a Black Sea sediment core taken in the western abyssal basin. The sediments were dated from a vertical profile of excess 210Pb. The 210Pb geochronology corresponded well to the 137Cs fallout record. A 20-year cyclic variability of carbon deposition has been traced in the dated ...

Small streams differing in sediment composition were compared in logged and forested reaches to determine effects of accumulated fine sediment on stream communities under different trophic conditions. Three stages of forest community succession were studied in the Cascade Mountai...

The report briefly describes the development of sediment criteria, discusses their utility and appropriate regulatory applications, and recommends steps to enhance the acceptance of sediment criteria by the regulatory and regulated communities.

The report briefly describes the development of sediment criteria, discusses their utility and appropriate regulatory applications, and recommends steps to enhance the acceptance of sediment criteria by the regulatory and regulated communities.

In conjunction with magnetostratigraphic results, a rock-magnetic investigation is carried out to clarify paleo-environmental changes in sedimentary sequences of piston core recovered from abyssal basin of Pacific. Study area is surrounded by Marshall islands to the east and Mariana islands to the west. Sampling site is located in abyssal basin between ...

GLORIA side-scan images provide new insight to the morphology and sedimentology of the Gulf of Alaska and show that tectonism strongly influences downslope and abyssal plain sediment transport. Along the Fairweather-Queen Charlotte transform margin south of Cross Sound short, chute-like canyons cross the slope to submarine-fan channels. At least one canyon ...

... Sediment Cores). Sediment and Vegetation Overview by Site Substrates, Biotic Community, and Disturbance Roatan-south, Honduras (wind, ...

Long-range transmission of explosion sounds over the Arctic abyssal plains commonly shows marked frequency dispersion of the bottom-interacting signals that follow the SOFAR signal. Hydrophones at depth and geophones on the ice surface were used as listening devices. The frequency dispersion of each pulse interacting with the flat bottom of the plain can be as strong as that ...

Multichannel and selected single-channel seismic lines of the continental margin sediments of the Colombia basin display compelling evidence for large accumulations of natural gas hydrate. Seismic bottom simulating reflectors (BSRs), interpreted to mark the base of the hydrate stability zone, are pronounced and very widespread along the entire Panama-Colombia lower continental ...