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Sample records for hull-mounted kongsberg simrad

  1. Hull-Mounted Acoustic Doppler Current Profiler Data (SADCP) collected aboard the NOAA Ship NANCY FOSTER during cruise NF-10-01 and NF-10-02

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Upper ocean current velocity measurements collected with NOAA Ship NANCY FOSTER's Teledyne RD Instruments 150 kHz hull-mounted acoustic Doppler current profiler...

  2. Acoustical characteristic predictions of a multi-layer system of a submerged vehicle hull mounted sonar simplified to an infinite planar model

    Directory of Open Access Journals (Sweden)

    Sung-Hee Kim

    2012-06-01

    Full Text Available Hull Mounted Sonar (HMS is a long range submerged vehicle's hull-mounted passive sonar system which detects low-frequency noise caused by machineries of enemy ships or submerged vehicles. The HMS needs a sound absorption /insulation multi-layer structure to shut out the self-noise from own machineries and to amplify signals from outside. Therefore, acoustic analysis of the multi-layer system should be performed when the HMS is designed. This paper simplified the HMS multi-layer system to be an infinite planar multi-layer model. Also, main excitations that influence the HMS were classified into mechanical, plane wave and turbulent flow excitation, and the investigations for each excitation were performed for various models. Stiffened multi-layer analysis for mechanical excitation and general multi-layer analysis for turbulent flow excitation were developed. The infinite planar multi-layer analysis was expected to be more useful for preliminary design stage of HMS system than the infinite cylindrical model because of short analysis time and easiness of parameter study.

  3. The distribution of silver specimens from the Kongsberg Silver Mines, Norway, 17th and 18th centuries

    NARCIS (Netherlands)

    Berg, B.I.; Nordrum, F.S.

    2004-01-01

    Specimens of native silver from the Kongsberg mines in Norway are world famous and have been distributed through sales and gifts during the whole period of mining from 1623 to 1958. Names of customers, the number of sold specimens and their silver content are documented in accounts which are

  4. Internationalization in the offshore sector and the use of strategic alliances. Kongsberg Offshore AS - A case study; Internasjonalisering i offshorebransjen og bruk av strategiske allianser. Kongsberg Offshore AS - et casestudium

    Energy Technology Data Exchange (ETDEWEB)

    Enger, Ole Peder; Andreassen, Yngve

    2000-06-01

    The structure of the Norwegian offshore sector is characterized by many small technology companies and only a few big ones. At the same time, operators prefer to deal with as few contractors as possible. Thus, the small technology companies must operate as subcontractors or cooperate as joint venture companies in order to win supply contracts. This report studies Kongsberg Offshore AS, or KOS, which is a daughter company of Food Machinery Corporation (FMC). KOS is a leading supplier of ''turnkey'' systems for sub see production and measuring systems and has had great success in its internationalization.

  5. The Kongsberg silver deposits, Norway: Ag-Hg-Sb mineralization and constraints for the formation of the deposits

    Science.gov (United States)

    Kotková, Jana; Kullerud, Kåre; Šrein, Vladimír; Drábek, Milan; Škoda, Radek

    2018-04-01

    The Kongsberg silver district has been investigated by microscopy and electron microprobe analysis, focusing primarily on the Ag-Hg-Sb mineralization within the context of the updated mineral paragenesis. The earliest mineralization stage is represented by sulfides, including acanthite, and sulfosalts. Native silver formed initially through breakdown of early Ag-bearing phases and later through influx of additional Ag-bearing fluids and silver remobilization. The first two generations of native silver were separated in time by the formation of Ni-Co-Fe sulfarsenides and the monoarsenide niccolite along rims of silver crystals. The presence of As-free sulfosalts and the absence of di- and tri-arsenides suggest a lower arsenic/sulfur activity ratio for the Kongsberg deposits compared to other five-element deposits. Native silver shows binary Ag-Hg and Ag-Sb solid solutions, in contrast to the ternary Ag-Hg-Sb compositions typical for other deposits of similar type. Antimonial silver together with allargentum, dyscrasite, and pyrargyrite was documented exclusively from the northern area of the district. Elsewhere, the only Sb-bearing minerals are polybasite and tetrahedrite/freibergite. Hg-rich silver (up to 21 wt% Hg) has been documented only in the central-western area. Myrmekite of freibergite and chalcopyrite reflects exsolution from an original Ag-poor tetrahedrite upon cooling, while myrmekite of pyrite and silver, forming through breakdown of low-temperature phases (argentopyrite or lenaite) upon heating, characterizes the Kongsberg silver district. Based on the stabilities of minerals and mineral assemblages, the formation of the silver mineralization can be constrained to temperatures between 180 and 250 °C.

  6. NOAA TIFF Image - 1 m Backscatter Mosaic of Abrir La Sierra Bank, PR (2007) collected using a Kongsberg EM 1002 (95 kHz) multibeam echosounder (NCEI Accession 0131853)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 1 meter resolution backscatter mosaic of the Abrir La Sierra Bank off the coast of western Puerto Rico, collected using a Kongsberg EM 1002...

  7. John Ellis, Jens Vigen and Mick Storr on handmade knits made for CERN by high-school teachers Inga Hanne Dokka (Kongsberg videregående skole) and Jolanta Nylund (Akademiet Drammen)

    CERN Multimedia

    Pantelia, Anna

    2014-01-01

    Mick Storr wearing a pull-over made by high-school teacher Jolanta Nylund, Akademiet, Drammen. John Ellis and Jens Vigen in jumpers knitted by high-school teacher Inga Hanne Dokka Kongsberg videregående skole.

  8. Section Transport Data calculated from Hull-Mounted Acoustic Doppler Current Profiler Velocities collected aboard the R/V GARUPPA during SUMMER 2010 SADCP Survey

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Volume transports were calculated through Virigin Passage and into and out of Vieques Sound (US Caribbean) between July 30,2010 and August 1, 2010 using a 300 kHz RD...

  9. Simrad em3002d Backscatter imagery of Penguin Bank, Molokai, Hawaii, USA

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Backscatter imagery extracted from gridded bathymetry of Penguin Bank, Molokai, Hawaii, USA. These data provide almost complete coverage between 0 and 100 meters....

  10. Hull-Mounted (shipboard) Acoustic Doppler Current Profiler (ADCP) data collected during shipboard surveys during 2010 and 2011 in Vieques Sound, Virgin Passage and surrounding regions (NODC Accession 0088063)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Teledyne RD Instruments Ocean Surveyor 150kHz and Workhorse 300kHz ADCPs were utilized during cruises conducted between March 2010 and April 2011 in Vieques Sound,...

  11. Correlating sea level rise still-stands to marine terraces and undiscovered submerged shoreline features in the Channel Islands (USA) using autonomous and remotely operated systems

    Science.gov (United States)

    Raineault, N.; Ballard, R. D.; Fahy, J.; Mayer, L. A.; Heffron, E.; Krasnosky, K.; Roman, C.; Schmidt, V. E.; McLeod, A.; Bursek, J.; Broad, K.

    2017-12-01

    In 2017, the Ocean Exploration Trust aggregated onboard and autonomous mapping technologies to identify and explore paleo shorelines and discover previously undocumented submerged shoreline features in and around the Channel Islands offshore of California. Broad area mapping was conducted with the hull mounted multibeam echosounder aboard the E/V Nautilus. This Kongsberg EM302 provided maps at 2-10 m resolution, at depths generally greater than 50 m. From this data marine terraces were identified for higher resolution mapping via an Autonomous Surface Vehicle (ASV). The precision data from the ASV's Kongsberg EM2040p echosounder allowed identification of the knickpoints associated with cliffs on the landward extent of each terrace. Sub-sea cave targets were identified using backscatter and slope maps from a combination of both the broad area and high resolution multibeam data. To ground-truth the targets identified through mapping, remotely operated vehicles (ROVs) and a highly specialized team of cave divers explored these targets. The results from the visual inspection were then fed back into the analysis fostering the rapid iteration of the onboard identification criteria and resulted in locating submerged shorelines containing numerous large caves, arches, and concretions. Caves were found at still-stands at 8, 33, 66, and 103 m depth at Santa Cruz Island, Santa Barbara Island platform, and Osborn Bank, along the vertical escarpment at the cliff-face and aligned with the strike of fractures in the volcanic rock. These terraces correspond to different sea level still-stands. ROV grab samples of fossiliferous marine terraces will provide ages and aid in reconstructions of sea level change and tectonic history for each location. Finally, caves were mapped in sub-cm resolution using a Kongsberg M3 sonar mounted vertically on the front of the ROV to test the capabilities of the system to provide accurate information about exterior dimensions and morphology.

  12. Nekton Interaction Monitoring System

    Energy Technology Data Exchange (ETDEWEB)

    2017-03-15

    The software provides a real-time processing system for sonar to detect and track animals, and to extract water column biomass statistics in order to facilitate continuous monitoring of an underwater environment. The Nekton Interaction Monitoring System (NIMS) extracts and archives tracking and backscatter statistics data from a real-time stream of data from a sonar device. NIMS also sends real-time tracking messages over the network that can be used by other systems to generate other metrics or to trigger instruments such as an optical video camera. A web-based user interface provides remote monitoring and control. NIMS currently supports three popular sonar devices: M3 multi-beam sonar (Kongsberg), EK60 split-beam echo-sounder (Simrad) and BlueView acoustic camera (Teledyne).

  13. Seafloor multibeam backscatter calibration experiment: comparing 45°-tilted 38-kHz split-beam echosounder and 30-kHz multibeam data

    Science.gov (United States)

    Ladroit, Yoann; Lamarche, Geoffroy; Pallentin, Arne

    2017-12-01

    Obtaining absolute seafloor backscatter measurements from hydrographic multibeam echosounders is yet to be achieved. We propose a low-cost experiment to calibrate the various acquisition modes of a 30-kHz Kongsberg EM 302 multibeam echosounder in a range of water depths. We use a 38-kHz Simrad EK60 calibrated fisheries split-beam echosounder mounted at 45° angle on the vessel's hull as a reference for the calibration. The processing to extract seafloor backscatter from the EK60 requires bottom detection, ray tracing and motion compensation to obtain acceptable geo-referenced backscatter measurements from this non-hydrographic system. Our experiment was run in Cook Strait, New Zealand, on well-known seafloor patches in shallow, mid, and deep-water depths. Despite acquisition issues due to weather, our results demonstrate the strong potential of such an approach to obtain system's absolute calibration which is required for quantitative use of backscatter strength data.

  14. High-resolution marine magnetic surveys for searching underwater cultural resources

    Directory of Open Access Journals (Sweden)

    S. Monti

    2006-06-01

    Full Text Available Recently two marine magnetic surveys, combined with the use of a multi-beam sonar (Kongsberg Marittime EM 300 multibeam: 30 KHz frequency echosounder for hydrographic purposes; acoustic lobe composed of 128 beams able to cover a 150° sector a side-scan sonar (Simrad MS 992 dual-frequency sidescan sonar with echo sounder transducers 150 Hz and 330 KHz and a Remote Operated Vehicle (ROV – a mobile tools used in environments which are too dangerous for humans, were executed in two sites respectively in the Ligurian Sea and the Asinara Gulf. The aim of these investigations was to test modern instrumentations and set new working procedures for searching underwater cultural resources. The collected and processed magnetic data yielded very satisfactory results: we detected submerged and buried features of cultural interest at both sites, at depths of 40 m and 400 m respectively.

  15. CRED Simrad em300 multibeam backscatter data from the submarine slope environment at Rose Island, American Samoa, South Pacific with 5 meter resolution in netCDF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Rose Island, American Samoa, South Pacific. These data provide coverage between 20 and 5000...

  16. CRED Simrad em300 multibeam backscatter data from the submarine slope environment at Rose Island, American Samoa, South Pacific with 5 meter resolution in GeoTIFF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Rose Island, American Samoa, South Pacific. These data provide coverage between 20 and 5000...

  17. CRED Simrad em300 multibeam backscatter data of Palmyra Atoll, Pacific Remote Island Areas, Central Pacific with 5 meter resolution in netCDF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of the lagoon, shelf, and slope environments of Palmyra Atoll, Pacific Island Areas, Central Pacific....

  18. CRED Simrad em300 multibeam backscatter data of Howland Island, Pacific Remote Island Areas, Central Pacific in GeoTIFF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of the shelf and slope environments of Howland Atoll, Pacific Island Areas, Central Pacific. These...

  19. CRED Simrad em300 multibeam backscatter data of Johnston Atoll, Pacific Remote Island Areas, Central Pacific in GeoTIFF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of the shelf and slope environments of Johnston Island, Pacific Island Areas, Central Pacific. These...

  20. Estimating deep seafloor interface and volume roughness parameters using the multibeam-hydrosweep system

    Digital Repository Service at National Institute of Oceanography (India)

    Chakraborty, B.; Schenke, H.W.; Kodagali, V.N.; Hagen, R.

    Utilizing a hull-mounted, multinarrow beam echosounder onboard RV Polarstern, variation of acoustic backscatter with incidence angles at two different sites in the Southern Oceans (Agulhas Plateau and the Riiser Larsen Sea) is measured. Using a...

  1. Temperature profiles and current measurements from the Nathaniel B. Palmer during the 1997 Dovetail cruise in the Southern Ocean (NODC Accession 9900243)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data collection includes temperature profiles from CTD casts and current measurements from hull-mounted ADCP system aboard the research vessel Nathaniel B....

  2. Advanced Computer Aids in the Planning and Execution of Air Warfare and Ground Strike Operations: Conference Proceedings, Meeting of the Avionics Panels of AGARD (51st) Held in Kongsberg, Norway on 12-16 May 1986

    Science.gov (United States)

    1986-02-01

    Natural Language (NL) interface. It is not as generic as Knowleoige Craft, i.e. it doeb not allow different ML procesoing paradigms. Language Craft is...or they may be scheduled to begin at m specific time in the scenario. Sosarion have been developed from the Motorized Rifle Regiment to the ombined

  3. Methane ebullition and fate in the Rhone River delta (Lake Geneva) and its subaquatic canyons

    Science.gov (United States)

    DelSontro, T.; Sollberger, S.; Corella, J. P.; Wehrli, B.; Girardclos, S.; Anselmetti, F. S.; Senn, D. B.

    2012-04-01

    There is increasing knowledge of the importance of inland waters as sources of atmospheric methane, but widespread variability of total and individual emission pathway estimates remain in the literature. Ebullition (bubbling) is potentially the most efficient transport mechanism from water bodies, particularly shallow water bodies or regions thereof where bubbles have the greatest chance of reaching the atmosphere. However, ebullition is one of the least monitored of the pathways, mostly due to its stochastic nature making it difficult to constrain spatially and temporally. Recent studies on a large tropical reservoir and a large European lake have shown that river deltas (i.e., localized regions of high allochthonous organic matter sedimentation) can be methane ebullition hot spots emitting disproportionate amounts of methane. Therefore, in this study the Rhone River delta (one Europe's most important rivers) of the Alp's largest lake, Lake Geneva, was surveyed for methane ebullition using a bubble size-calibrated 120 kHz split-beam echosounder (Simrad EK60, Kongsberg Maritime). Extensive ebullition was found in the current river delta complex in proximity to the river inflow, which is the major source of atmospheric methane emission in the entire 100 km2 deltaic region. As water depths approach 100 m, ebullition is constrained to only the top levees of the 10 - 40 m high walls of the subaquatic canyon formed by the plunging Rhone River. Ebullition occurs to depths over 200 m on the levee of the active canyon, where CTD profiles suggest that Rhone River water does extend that far along the canyon. As bubble dissolution depends on release depth and bubble size, which was estimated from the rise velocity of deep bubbles, it was discovered that bubbles emitted from 100 m or deeper would not reach the surface; thus the proximal delta remains the prominent methane source. Eight other canyons exist in the delta complex, of which two non-active canyons formed by previous

  4. Cruise report; RV Coastal Surveyor Cruise C1-99; multibeam mapping of the Long Beach, California continental shelf; April 12 through May 19, 1999

    Science.gov (United States)

    Gardner, James V.; Hughes-Clarke, John E.; Mayer, Larry A.

    1999-01-01

    dual Kongsberg Simrad EM3000D.

  5. Sonar performance indicator CSCI - development of a tactical decision aid. (abstract)

    NARCIS (Netherlands)

    Lentze, S.G.; Benders, F.P.A.; Dekker, J.J.M.

    1999-01-01

    The sonar performance indicator (SPI) will be an integral part of the modernised command and control system of the RNIN Alkmaar class minehunters. The SPI will act as a tactical decision aid, supporting both the detection sonar operator as well as the commanding officer, for the hull mounted sonar

  6. Sensor Management for Tactical Surveillance Operations

    Science.gov (United States)

    2007-11-01

    active and passive sonar for submarine and tor- pedo detection, and mine avoidance. [range, bearing] range 1.8 km to 55 km Active or Passive AN/SLQ-501...Active AN/SQS-510 General Dynam- ics Hull-mounted active and passive sonar and variable depth active and passive sonar for submarine and tor- pedo

  7. Department of the Navy Amended FY 1992/FY 1993 Biennial Budget Estimates. R,D,T, and E Descriptive Summaries Submitted to Congress January 1992. Research, Development, Test and Evaluation, Navy

    Science.gov (United States)

    1992-01-01

    Situ Mode Assssmnt System ( SINKS ), AN/SQS-S3B/C hull mounted sonars, and the Light Airborne Multi-Purpose System (LAWS) NK III signal processor) in...correlates both with subtle temperature changes in the brain’s hippocampus and with alterations of specific neurohormones in that region of the brain

  8. NOAA Ship Pisces Cruise PC-11-06 (14) Multibeam Sonar Workshop on NOAA Ship Pisces (EK60)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The overall objective is to familiarize participating scientists with PISCES multibeam echosounder (Simrad ME70) configuration, operation, calibration and data...

  9. EOP Bioacoustics

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data contain shipboard bioacoustics data collected in the Pacific, both pelagic and near shore environments. Data is collected using Simrad EK60 splitbeam...

  10. NOAA Ship Pisces Cruise PC-11-06 (14) Multibeam Sonar Workshop on NOAA Ship Pisces (ME70)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The overall objective is to familiarize participating scientists with PISCES multibeam echosounder (Simrad ME70) configuration, operation, calibration and data...

  11. Deep-Pelagic Nekton Dynamics of the Gulf of Mexico (DEEPEND)- DP02 (EK80)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Patterns in acoustically derived biological scatter through the water column will be collected with multi-frequency scientific echosounders (Simrad EK60) operating...

  12. Penguin Banks Acoustic Bottomfish Survey (SE0703L2, EK60)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Narrow-band, split-beam acoustic data were collected using a Simrad EK60 system operating at 38 and 120 kHz frequencies along predetermined transects to collect...

  13. Deep-Pelagic Nekton Dynamics of the Gulf of Mexico (DEEPEND)- DP01 (EK80)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Patterns in acoustically derived biological scatter through the water column will be collected with multi-frequency scientific echosounders (Simrad EK60) operating...

  14. NOAA Ship Pisces Cruise PC1106 (14) Multibeam Sonar Workshop

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The overall objective is to familiarize participating scientists with PISCES multibeam echosounder (Simrad ME70) configuration, operation, calibration and data...

  15. Acoustic Split-Beam Echosounder Data (EK60)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Southeast Fisheries Science Center Mississippi Laboratories collects data using Simrad EK60 scientific split-beam acoustic echosounders during resource...

  16. Acoustic Multi-Beam Echosounder Data (ME70)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Southeast Fisheries Science Center Mississippi Laboratories collects data using a Simrad ME70 scientific multibeam acoustic echosounder during resource...

  17. AFSC/REFM: Acoustics from vessels of opportunity - EBS factory-trawlers

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The dataset is comprised of acoustic data recorded from SIMRAD ES-60 and ES-70 echosounders on board commercial fishing vessels fishing walleye pollock in the Bering...

  18. CRED 20 m Gridded bathymetry of Brooks Banks and St. Rogatien Bank, Hawaii, USA (Arc ASCII format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded bathymetry (20m) of the shelf and slope environments of Brooks Banks and St. Rogatien, Hawaii, USA. The ASCII includes multibeam bathymetry from the Simrad...

  19. Penguin Banks Acoustic Bottomfish Survey (SE0902L2, EK60)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Narrow-band, split-beam acoustic data were collected using a Simrad EK60 system operating at 38, 70, and 120 kHz frequencies along predetermined transects to collect...

  20. CRED Fagatele Bay National Marine Sanctuary Bathymetric Position Index Habitat Structures 2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetric Position Index (BPI) Structures are derived from derivatives of Simrad EM-3000 multibeam bathymetry (1 m and 3 m resolution). BPI structures are...

  1. CRED Fagatele Bay National Marine Sanctuary Bathymetric Position Index Habitat Zones 2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetric Position Index (BPI) Zones derived from derivatives of Simrad EM-3000 multibeam bathymetry (3 m resolution). BPI zones are surficial characteristics of...

  2. The Influence of Shock-Induced Air Bubble Collapse Resulting from Underwater Explosive Events

    Science.gov (United States)

    2012-06-01

    this process occurs, the sphere migrates towards the water surface due to Archimedes ’ principle . 7 Figure 2 provides a good visualization of the... application , this bubble layer would be made up of countless individual bubbles delivered by a hull-mounted pressurized air system. The computer...4]) 6 1. Explosive Materials Common explosive materials used in naval applications include Trinitrotoluene (TNT), Torpedo Explosive (TORPEX

  3. Continental Shelf Embayments of the Eastern Margin of the Philippines; Lamon Bay Stratification & Circulation

    Science.gov (United States)

    2012-09-30

    in 2011. Data from R/V Revelle hull mounted ADCP. The hull ADCP and the CTD thermohaline stratification reveal a shift in circulation pattern...Philippines; Lamon Bay Stratification & Circulation Arnold L. Gordon Lamont-Doherty Earth Observatory 61 Route 9W Palisades, NY 10964-8000... circulation , stratification and the Shelf-Slope interaction, and the resultant ocean productivity, within a major embayment, Lamon Bay, of the eastern

  4. EX1203: Florida Escarpment and Straits Exploration on NOAA Ship Okeanos Explorer between 20120505 and 20120523

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — EX1203 of NOAA Ship Okeanos Explorer (EX) will run its Kongsberg EM302 multibeam sonar survey system 24 hours per day with periodic XBT casts for calibration. One to...

  5. Okeanos Explorer (EX1706): Johnston Atoll (ROV/Mapping)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations will include the use of the ship's deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries sonars, Knudsen 3260 chirp...

  6. NOAA TIFF Image - 1 m Backscatter Mosaic of Bajo de Cico, Puerto Rico, Project NF-07-06, 2007, UTM 19 NAD83 (NCEI Accession 0131853)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 1 meter resolution backscatter mosaic of Bajo de Cico off the coast of western Puerto Rico, collected using a Kongsberg EM 1002 (95 kHz)...

  7. Oceanographic data collected during the EX1602 Mission System Shakedown/CAPSTONE Mapping on NOAA Ship OKEANOS EXPLORER in the North Pacific Ocean from 2016-02-12 to 2016-02-17 (NCEI Accession 0145342)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations used the ship's deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries sonars, Knudsen 3260 chirp sub-bottom profiler...

  8. Okeanos Explorer (EX1705): American Samoa, Kingman/Palmyra, Jarvis (ROV & Mapping)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations will include the use of the ship's deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries sonars, Knudsen 3260 chirp...

  9. NOAA TIFF Image - 2 m Backscatter Mosaic of Isla de Mona, PR, Project NF-07-06, 2007, UTM 19 NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 2 meter resolution backscatter mosaic of the southern coast of Isla de Mona, collected using a Kongsberg EM 1002 (95 kHz) multibeam...

  10. NOAA TIFF Image - 2 m Backscatter Mosaic of Isla de Mona, Puerto Rico, Project NF-07-06, 2007, UTM 19 NAD83 (NCEI Accession 0131853)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 2 meter resolution backscatter mosaic of the southern coast of Isla de Mona, collected using a Kongsberg EM 1002 (95 kHz) multibeam...

  11. EX1101: Ship Shakedown and Patch Tests on NOAA Ship Okeanos Explorer (EM302)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This project will involve the shakedown of all Okeanos Explorer ship capabilities and a patch test of the Kongsberg EM302 multibeam system. Operations for this...

  12. EX1101: Ship Shakedown and Patch Tests on NOAA Ship Okeanos Explorer between March 16 and April 1, 2011

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This project will involve the shakedown of all Okeanos Explorer ship capabilities and a patch test of the Kongsberg EM302 multibeam system. Operations for this...

  13. Okeanos Explorer (EX1703): Howland/Baker PRIMNM and PIPA (ROV/Mapping)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations will include the use of the ship's deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries sonars, Knudsen 3260 chirp...

  14. Okeanos Explorer (EX1702): American Samoa Expedition: Suesuega o le Moana o Amerika Samoa (ROV/Mapping)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations will include the use of the ship's deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries sonars, Knudsen 3260 chirp...

  15. Terrestrial-style slow-moving earthflow kinematics in a submarine landslide complex

    Science.gov (United States)

    Joshu J. Mountjoy; Jim McKean; Philip M. Barnes; Jarg R. Pettinga

    2009-01-01

    Morphometric analysis of Simrad EM300 multibeam bathymetric DEMs reveals details of deformation patterns in a ~145 km2 submarine landslide complex that are commonly associated with slow-moving earthflows in terrestrial settings. This mode of failure, where existing landslide debris is remobilised repeatedly along discrete shear boundaries and is...

  16. in situ measurements of the acoustic target strength of cape horse ...

    African Journals Online (AJOL)

    The acoustic target strength (TS) of Cape horse mackerel Trachurus trachurus capensis was measured in situ at 38 kHz during two surveys over the Namibian continental shelf in 1998 and 1999 using a SIMRAD EK500 echosounder/ES38D submersible split-beam transducer. Scattered aggregations of horse mackerel ...

  17. Echosounder data archive

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — An archive of multi-frequency and multi-beam echosounder data (Simrad .raw format), collected as part of SWFSC-FRD surveys of the U.S. west coast between San Diego,...

  18. Gridded bathymetry of Penguin Bank, Hawaii, USA

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded bathymetry (5 m cell size) of Penguin Bank, Hawaii, USA. The netCDF grid and ArcGIS ASCII file include multibeam bathymetry from the Simrad EM3002d, and...

  19. Gridded multibeam bathymetry and SHOALS LIDAR bathymetry of Penguin Bank, Hawaii, USA

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded bathymetry (5 m cell size) of Penguin Bank, Hawaii, USA. The netCDF grid and ArcGIS ASCII file include multibeam bathymetry from the Simrad EM3002d, and...

  20. Okeanos Explorer (EX1602): Mission System Shakedown/CAPSTONE Mapping

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations will use the ship’s deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries sonars, Knudsen 3260 chirp sub-bottom...

  1. Real time observation

    OpenAIRE

    Smedsvik, Vegard; Bekkevold, Svein; Jansen, Carl Peder; Schinnes, Alexander

    2016-01-01

    Kongsberg Defence & Aerospace har behov for å se på hvordan ny og fremtidsrettet teknologi kan anvendes innenfor deres forskjellige observasjonssystemer. Oppgaven går derfor ut på å se på nye innovative løsninger for hvordan bilde og informasjon fra et videokamera skal nå operatøren av systemet.

  2. 76 FR 46729 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Science.gov (United States)

    2011-08-03

    ... shallow hazards and site clearance surveys would use a towed airgun cluster consisting of four, 10-in\\3... cluster, single 10 in\\3\\ airgun, Kongsberg SBP3000 sub-bottom profiler, GeoAcoustics 160D side-scan sonar...'' binoculars (e.g., 25 x 150 power) from high perches on large, stable platforms; (3) pairing the use of ``big...

  3. Okeanos Explorer (EX1701): Kingman/Palmyra, Jarvis (Mapping)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations will include the use of the ship’s deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries sonars, ADCPs, and Knudsen...

  4. Okeanos Explorer (EX1605L2): CAPSTONE CNMI and Mariana Trench MNM (Mapping)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations will use the ship’s deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries sonars, ADCPs, and Knudsen 3260 chirp...

  5. Okeanos Explorer (EX1607): CAPSTONE Wake Island PRI MNM (Mapping)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations will include 24 hour/day mapping operations using the ship’s deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries...

  6. EX1202L1: Gulf of Mexico Exploration on NOAA Ship Okeanos Explorer between 20120227 and 20120314

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — EX1202 Leg I of NOAA Ship Okeanos Explorer (EX) is focused on exploration of North Eastern region of Gulf of Mexico using the ships’ Kongsberg EM302 multibeam...

  7. Ocean mixing in deep-sea trenches: New insights from the Challenger Deep, Mariana Trench

    NARCIS (Netherlands)

    van Haren, H.; Berndt, C.; Klaucke, I.

    2017-01-01

    Reliable very deep shipborne SBE 911plus Conductivity Temperature Depth (CTD) data to within 60 m from the bottom and Kongsberg EM122 0.5° × 1° multibeam echosounder data are collected in the Challenger Deep, Mariana Trench. A new position and depth are given for the deepest point in the world's

  8. Okeanos Explorer (EX1608): FY17 Ship and ROV Shakedown

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations will use the ship’s deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries sonars, ADCPs, and Knudsen 3260 chirp...

  9. Okeanos Explorer (EX1606): CAPSTONE Wake Island Unit PRIMNM (ROV & Mapping)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Operations will use the ship’s deep water mapping systems (Kongsberg EM302 multibeam sonar, EK60 split-beam fisheries sonars, ADCPs, and Knudsen 3260 chirp...

  10. EX1201: Ship Shakedown and Patch Tests on NOAA Ship Okeanos Explorer between 20100214 and 20120223

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — EX1201 is the 2012 shakedown mission of NOAA ship Okeanos Explorer (EX) and will perform system patch tests of the vessel’s Kongsberg EM302 multibeam sonar....

  11. Multinational Coproduction of Military Aerospace Systems.

    Science.gov (United States)

    1981-10-01

    Kongsberg Interference blanker Novatronics G.A. Ring Rate gyro Northrop Eongsberg Stores manegement set General Dynamics Kongsbarg Generator. 40 EVA control...34 NATO’s Fifteen Nations, April/May 1978, pp. 88-95. Hiller , John, The Economic Implications of NATO Arms Collaboration, The Analytic Sciences

  12. Minesniper

    Directory of Open Access Journals (Sweden)

    B. Smestad

    1996-01-01

    Full Text Available The flight control system of a minehunting ROV-type weapon developed by SIMRAD is presented. The system is separated into lightly interacting subsystems, and autopilots are designed for steering, diving and speed control. The design of the separate controllers is based on PI, forward loop and sliding mode techniques. The diving control system, using the battery-packet as actuator, is specially examined. Results from sea testing show performance and stability for the autopilots.

  13. Distribution of mesopelagic micronekton in the Arabian Sea during the winter monsoon

    Digital Repository Service at National Institute of Oceanography (India)

    Karuppasamy, P.K.; Muraleedharan, K.R.; DineshKumar, P.K.; Nair, M.

    and nitrite were obtained using an autoanalyser (SKALAR, Model 51001-1), following the principles of Grasshoff et al. 198322. The acoustic detection of DSL was made by two scientific Echo sounders: Simrad, EK 400 and EK 200 (38 and 120 KHz). The gear... for the temperature, salinity, dissolved oxygen, nitrate and nitrite contour. KARUPPASAMY et al. : MESOPELAGIC MICRONEKTON IN THE ARABIAN SEA 229 Biodiversity indices Diversity is a concise expression of how individuals of a community are distributed...

  14. Seismic Discrimination

    Science.gov (United States)

    1979-09-30

    Plate Tectonics ,’ in The Earth: Its Origin. Structure and Evolution (Academic Press. London. f9-79). pp. 491-542. 185. M. A. Chinnery. "A Comparison of...stations in Eurasia-SHIO (Shillong, india), ANTO ( Ankara , Turkey), GRFO (Graefenberg, Germany), and KONO (Kongsberg, Norway) started producing data, and we...34 Tectonics of the Caribbean and Middle America Regions from Focal Mechanisms and Seismicity." Geol. Soc. Am. Bull. 80. 1639-1684 (1969). 10. T. J

  15. Sensory impairments in community health care: a descriptive study of hearing and vision among elderly Norwegians living at home

    OpenAIRE

    Haanes GG; Kirkevold M; Horgen G; Hofoss D; Eilertsen G

    2014-01-01

    Gro Gade Haanes,1 Marit Kirkevold,2 Gunnar Horgen,1 Dag Hofoss,2 Grethe Eilertsen1 1Buskerud and Vestfold University College, Kongsberg, Norway; 2University of Oslo, Oslo, Norway Background: Hearing and vision impairments increase with age and are common risk factors for functional decline reduced social participation and withdrawal. Objective: Describe the hearing and vision of home care patients older than 80 years. Methods: Ninety-three older adults (80+ years) receiving home care were sc...

  16. AGOR 28: SIO Shipyard Representative Bi-Weekly Progress Report

    Science.gov (United States)

    2016-06-18

    an open Trial Card. I believe Kongsberg is scheduled to retune the system. • Blue Drive Shore-based Spares – ALM, AIM and Propulsion Motor drives...failed due to shorted temperature sensor at the Tunnel Thruster motor . A small rectifier was found to have failed in the terminal block found in the...J-1 at sustained speed. See Airborne Noise Survey Report (DI-032-006) for more information (Delete after RFW approved) 1137 HVAC - There were no

  17. Variable speed hydrodynamic model of anAuv utilizing cross tunnel thrusters

    Science.gov (United States)

    2017-09-01

    controllability at low speeds to safely and effectively dock the vehicle in a subsea environment. Kongsberg, REMUS’s production company , has released a REMUS...actual REMUS controllers’ design and parameters being proprietary information. However, even with a slightly different controller implemented in the model...performed on the model until the behavior of the modeled REMUS closely approximated the characteristic dive and thrust behaviors of the actual vehicle

  18. The Application of a Free Swimming Remotely Operated Vehicle in Aquaculture

    Directory of Open Access Journals (Sweden)

    R. Klepaker

    1987-01-01

    Full Text Available In 1985, SINTEF and SIMRAD Subsea A/S started to develop an autonomous free swimming vehicle. The project was to develop a prototype of a small vehicle, in order to obtain knowledge and experience in designing, controlling and operating such vehicles. This was ready for testing at the end of 1985. The vehicle is controlled by an acoustic data telemetry system. The vehicle has a built-in television camera and containers for other sensors. It is suitable for inspection purposes. This paper describes the vehicle and some of the principles used.

  19. Inferring the acoustic dead-zone volume by split-beam echo sounder with narrow-beam transducer on a noninertial platform.

    Science.gov (United States)

    Patel, Ruben; Pedersen, Geir; Ona, Egil

    2009-02-01

    Acoustic measurement of near-bottom fish with a directional transducer is generally problematical because the powerful bottom echo interferes with weaker echoes from fish within the main lobe but at greater ranges than that of the bottom. The volume that is obscured is called the dead zone. This has already been estimated for the special case of a flat horizontal bottom when observed by an echo sounder with a stable vertical transducer beam [Ona, E., and Mitson, R. B. (1996). ICES J. Mar. Sci. 53, 677-690]. The more general case of observation by a split-beam echo sounder with a transducer mounted on a noninertial platform is addressed here. This exploits the capability of a split-beam echo sounder to measure the bottom slope relative to the beam axis and thence to allow the dead-zone volume over a flat but sloping bottom to be estimated analytically. The method is established for the Simrad EK60 scientific echo sounder, with split-beam transducers operating at 18, 38, 70, 120, and 200 kHz. It is validated by comparing their estimates of seafloor slope near the Lofoten Islands, N67-70, with simultaneous measurements made by two hydrographic multibeam sonars, the Simrad EM100295 kHz and EM30030 kHz systems working in tandem.

  20. Evidence of recent volcanic activity on the ultraslow-spreading Gakkel ridge.

    Science.gov (United States)

    Edwards, M H; Kurras, G J; Tolstoy, M; Bohnenstiehl, D R; Coakley, B J; Cochran, J R

    2001-02-15

    Seafloor spreading is accommodated by volcanic and tectonic processes along the global mid-ocean ridge system. As spreading rate decreases the influence of volcanism also decreases, and it is unknown whether significant volcanism occurs at all at ultraslow spreading rates (<1.5 cm yr(-1)). Here we present three-dimensional sonar maps of the Gakkel ridge, Earth's slowest-spreading mid-ocean ridge, located in the Arctic basin under the Arctic Ocean ice canopy. We acquired this data using hull-mounted sonars attached to a nuclear-powered submarine, the USS Hawkbill. Sidescan data for the ultraslow-spreading (approximately 1.0 cm yr(-1)) eastern Gakkel ridge depict two young volcanoes covering approximately 720 km2 of an otherwise heavily sedimented axial valley. The western volcano coincides with the average location of epicentres for more than 250 teleseismic events detected in 1999, suggesting that an axial eruption was imaged shortly after its occurrence. These findings demonstrate that eruptions along the ultraslow-spreading Gakkel ridge are focused at discrete locations and appear to be more voluminous and occur more frequently than was previously thought.

  1. Vertical migration and diel feeding periodicity of the skinnycheek lanternfish (Benthosema pterotum) in the Red Sea

    KAUST Repository

    Dypvik, Eivind

    2012-11-13

    The vertical migration and diel feeding periodicity of the skinnycheek lanternfish (Benthosema pterotum) were studied by use of a hull-mounted 38 kHz echo sounder, ROV-deployments and net-sampling at two locations (∼24°48′N, ∼36°15′E and ∼21°27′N, ∼38°5′E) in the central Red Sea. The mesopelagic zone of the Red Sea represents an unusual environment with very high temperatures (∼22 °C) and low zooplankton concentrations (<10 individuals m−3 below 600 m). The skinnycheek lanternfish performed normal diel vertical migration from ∼500 to 750 m during daytime to the epipelagic zone (upper ∼200 m) at night. A strict feeding periodicity occurred; with the skinnycheek lanternfish foraging on zooplankton throughout the night, while rapidly digesting the preceding nocturnal meal in the warm mesopelagic region. We hypothesize that the constrained epipelagic distribution of zooplankton and the unusual warm waters of the Red Sea force the whole population to ascend and feed in epipelagic waters every night, as the prey-ration eaten each night is fully digested at mesopelagic depths during daytime.

  2. Active control of passive acoustic fields: passive synthetic aperture/Doppler beamforming with data from an autonomous vehicle.

    Science.gov (United States)

    D'Spain, Gerald L; Terrill, Eric; Chadwell, C David; Smith, Jerome A; Lynch, Stephen D

    2006-12-01

    The maneuverability of autonomous underwater vehicles (AUVs) equipped with hull-mounted arrays provides the opportunity to actively modify received acoustic fields to optimize extraction of information. This paper uses ocean acoustic data collected by an AUV-mounted two-dimensional hydrophone array, with overall dimension one-tenth wavelength at 200-500 Hz, to demonstrate aspects of this control through vehicle motion. Source localization is performed using Doppler shifts measured at a set of receiver velocities by both single elements and a physical array. Results show that a source in the presence of a 10-dB higher-level interferer having exactly the same frequency content (as measured by a stationary receiver) is properly localized and that white-noise-constrained adaptive beamforming applied to the physical aperture data in combination with Doppler beamforming provides greater spatial resolution than physical-aperture-alone beamforming and significantly lower sidelobes than single element Doppler beamforming. A new broadband beamformer that adjusts for variations in vehicle velocity on a sample by sample basis is demonstrated with data collected during a high-acceleration maneuver. The importance of including the cost of energy expenditure in determining optimal vehicle motion is demonstrated through simulation, further illustrating how the vehicle characteristics are an integral part of the signal/array processing structure.

  3. A GIS Library of Multibeam Data for Massachusetts Bay and the Stellwagen Bank National Marine Sanctuary, Offshore of Boston, Massachusetts

    Science.gov (United States)

    Butman, Bradford; Valentine, Page C.; Middleton, Tammie J.; Danforth, William W.

    2007-01-01

    Introduction The U.S. Geological Survey (USGS) has mapped the sea floor of the Stellwagen Bank National Marine Sanctuary and western Massachusetts Bay, offshore of Boston, Massachusetts (figure 1a, figure 1b). The mapping was carried out using a Simrad Subsea EM1000 Multibeam Echo Sounder (95 kHz) on the Frederick G. Creed on four cruises between 1994 and 1998. The mapping was conducted in cooperation with the National Oceanic and Atmospheric Administration (NOAA) and with support from the Canadian Hydrographic Service and the University of New Brunswick. This GIS Library contains images and grids of bathymetry, shaded relief bathymetry, and backscatter intensity data from these surveys in an Environmental Systems Research Institute (http://www.esri.com) (ESRI) ArcMap 9.1 Geographic Information System (GIS) project. The shapefiles, images, grids and associated metadata may also be downloaded individually. Descriptions and interpretations of the data are available in a series of published maps.

  4. Environmental assessment of saltmarshes at Patos Lagoon Estuary - RS

    OpenAIRE

    Marangoni, Juliano César; Costa, César Serra Bonifácio

    2009-01-01

    Um cruzeiro de prospecção hidroacústica foi realizado ao longo da plataforma, talude e região oceânica adjacente da costa Nordeste do Brasil, incluindo Bancos Oceânicos do Ceará, Atol das Rocas e Arquipélagos de Fernando de Noronha e de São Pedro e São Paulo. Foram prospectadas 1.653 milhas náuticas para avaliar distribuição e abundância de espécies de pequenos peixes pelágicos. Dados hidroacústicos foram coletados com uma ecossonda científica SIMRAD EK 500 operando em 38 kHz. Os ...

  5. Ecobatimetria e características acústicas do leito oceânico na região do canal do Albardão - Rio Grande do Sul - Brasil

    OpenAIRE

    Campos, Paula Costa; Weigert, Stefan Cruz; Madureira, Lauro Antonio Saint Pastous

    2009-01-01

    O canal do Albardão estende-se desde as proximidades de Punta del Este (Uruguai) até aproximadamente a latitude do Farol do Albardão (RS), sobre poços de lama que caracterizam antigos canais de drenagem do Rio da Prata. A partir de dados hidroacústicos coletados sobre a plataforma continental sul do Rio Grande do Sul, através de uma eco-sonda científica EK500 SIMRAD, com freqüência de 38 kHz, foram gerados perfis batimétricos com dados de dureza acústica do fundo. Foi verificado que a extensã...

  6. Using continuous underway isotope measurements to map water residence time in hydrodynamically complex tidal environments

    Science.gov (United States)

    Downing, Bryan D.; Bergamaschi, Brian; Kendall, Carol; Kraus, Tamara; Dennis, Kate J.; Carter, Jeffery A.; von Dessonneck, Travis

    2016-01-01

    Stable isotopes present in water (δ2H, δ18O) have been used extensively to evaluate hydrological processes on the basis of parameters such as evaporation, precipitation, mixing, and residence time. In estuarine aquatic habitats, residence time (τ) is a major driver of biogeochemical processes, affecting trophic subsidies and conditions in fish-spawning habitats. But τ is highly variable in estuaries, owing to constant changes in river inflows, tides, wind, and water height, all of which combine to affect τ in unpredictable ways. It recently became feasible to measure δ2H and δ18O continuously, at a high sampling frequency (1 Hz), using diffusion sample introduction into a cavity ring-down spectrometer. To better understand the relationship of τ to biogeochemical processes in a dynamic estuarine system, we continuously measured δ2H and δ18O, nitrate and water quality parameters, on board a small, high-speed boat (5 to >10 m s–1) fitted with a hull-mounted underwater intake. We then calculated τ as is classically done using the isotopic signals of evaporation. The result was high-resolution (∼10 m) maps of residence time, nitrate, and other parameters that showed strong spatial gradients corresponding to geomorphic attributes of the different channels in the area. The mean measured value of τ was 30.5 d, with a range of 0–50 d. We used the measured spatial gradients in both τ and nitrate to calculate whole-ecosystem uptake rates, and the values ranged from 0.006 to 0.039 d–1. The capability to measure residence time over single tidal cycles in estuaries will be useful for evaluating and further understanding drivers of phytoplankton abundance, resolving differences attributable to mixing and water sources, explicitly calculating biogeochemical rates, and exploring the complex linkages among time-dependent biogeochemical processes in hydrodynamically complex environments such as estuaries.

  7. New sedimentological evidence supporting a catastrophic meltwater discharge event along the Beaufort margin, Arctic Ocean

    Science.gov (United States)

    Klotsko, S.; Driscoll, N. W.; Keigwin, L. D.; Mendenhall, B.

    2015-12-01

    In 2013, a cruise on the USCGC Healy mapped the Beaufort margin from Barrow, AK into the Amundsen Gulf using a towed CHIRP subbottom profiler and a hull-mounted Knudsen CHIRP subbottom profiler to study the deglaciation of the margin. Sediment cores were also acquired. New grain size analyses for three sediment cores will be presented. These records help constrain the flooding events captured in the existing grain size data from JPC 15, just east of the Mackenzie trough. This core shows evidence of multiple ice rafted debris events that were likely sourced from the retreat of the Amundsen ice stream. These layers have peaks in grain size around ~20 microns compared to the ~5 micron average for the rest of the core. The grain size peaks correlate to the high amplitude reflectors observed in the seismic CHIRP data. Similar reflectors are observed in the seismic data from two of the new core locations, one in the Mackenzie trough and one east of the trough. The seismic data from these stations also record a thick sediment package that is ~7 meters thick at its depocenter. This layer is interpreted to record a massive meltwater discharge event that entered the Arctic via the Mackenzie River. Oxygen isotope data from JPC 15 support an event at this location based on the covarying benthic and planktonic records. In our conceptual model, the pulses of freshwater from the Amundsen Gulf likely freshened the margin sufficiently that the major discharge event was then able to push the system over the edge. This catastrophic glacial lake draining out the Mackenzie River into the Beaufort Sea and export out of the Arctic into the North Atlantic caused diminished meridional overturning circulation - slowing of the conveyor belt thermohaline circulation - which, in turn, potentially caused the Younger Dryas cold period.

  8. Quantifying the impact of an upwelling filament on the physical-chemical-biological interactions off SW Iberia

    Science.gov (United States)

    Cravo, A.; Sanchez, R.; Monteiro, C.; Cardeira, S.; Madureira, M.; Rita, F.; Relvas, P.

    2017-12-01

    Upwelling filaments are mesoscale structures of cold water that stretch seaward in a tongue-like shape with origin in the coastal upwelling zone. Filaments off the Iberian Peninsula are recurrent, showing similarities with those in the Californian coast. The Cape São Vicente, the SW tip of the Iberian Peninsula, is the root of recurrent filaments observed in the satellite imagery during the upwelling season. However, the understanding of its physical and chemical impact on the biological productivity is rather limited. There, a relatively small filament ( 80 km long) was investigated through remote sensing and in situ multidisciplinary observations during an upwelling favourable wind relaxation event, but just after an intense upwelling period. A total of 42 CTD+Rosette casts up to 400 m depth were distributed on an almost regular grid of 15 km mean spacing guided by guided by satellite SST imagery transmitted to the ship in near-real time. The parameters sampled during the sea campaign included: velocity field sampled along the ship track through a hull-mounted 38 kHz RDI ADCP, meteorological variables, temperature, salinity, chlorophyll a, dissolved oxygen, nitrate, phosphate, silicate, cadmium, lead and zinc. The extent of the impact of the filament was evaluated by quantifying the cross-shelf transports of several properties. The amounts conveyed by the filament were much stronger than those expected by the wind-driven Ekman mechanism, showing that it represents an efficient feature for the exchange of water, dissolved and particulate matter from the productive shelf towards the oligotrophic offshore region. Considering the periods of strong upwelling events and the extent of their duration along the year, the amounts of exported matter will certainly enhance the biological productivity of these waters, including its fisheries. These filament data contribute to better understand the physical-chemical-biological interactions of this regional ecosystem.

  9. Bathymetry & Geomorphology - A New Seafloor Mapping of the Israeli Exclusive Economic Zone

    Science.gov (United States)

    Tibor, G.; Hall, J. K.; Kanari, M.; Sade, R. A.; Sade, H.; Amit, G.; Gur-Arie, L.; Ketter, T.

    2017-12-01

    Recent extensive activities of oil and gas exploration and production companies in the Israeli Exclusive Economic Zone (EEZ) raised the need for an up-to-date baseline mapping of the seafloor to assist policy makers. The baseline mapping focused on bathymetry, geomorphology, geology, biodiversity, infauna and habitat in order to compile a sensitivity map for the Petroleum Commissioner in the Ministry of Energy in the bid for opening the sea to new natural gas and oil explorations. The Israeli EEZ covers an area of 25,950 sq. km. and reaches a maximum water depth of 2,100 m. It is located within the Levantine Basin, a zone of compression and strike-slip tectonics as Africa pushes into Eurasia. These forces operate on a half kilometer thick of Messinian evaporates and over a dozen kilometers of Pliocene and Pleistocene sediments to produce a complex seafloor morphology. The margin is cut by numerous slumps and canyons, while the basin is traversed by deep sea channels emptying into the moat around Eratosthenes Seamount farther north. The bathymetric and geomorphological mapping was done in three phases using Kongsberg and Elac multibeam sonars installed on different research vessels. The last phase (Aug.-Sept., 2016) covering depths from 1,400 to 2,100 m used the Kongsberg EM302 sonar installed on our new governmental research vessel Bat Galim. It has "state of the art" capabilities to map, sample and analyze the water column, seafloor and sub-bottom from water depths of 10m to 7,000 m. These mapping capabilities are unique in our region, the Eastern Mediterranean and the Red Sea, so we hope to promote research collaborations with our neighbors.

  10. Structural Mapping and Geomorphology of Ireland's Southwest Continental Shelf Using High Resolution Sonar

    Science.gov (United States)

    Bowden, S.; Wireman, R.

    2016-02-01

    Bathymetric surveys were conducted on the continental shelf off the southwest coast of County Cork, Ireland by the Marine Institute of Ireland, the Geological Survey of Ireland, and the INFOMAR project. Data were collected from July 2006 through September 2014 using a Kongsberg EM2040 multibeam echosounder aboard the R/Vs Celtic Voyager and Keary, and a Kongsberg EM1002 on the R/V Celtic Explorer. Sonar data were post-processed with CARIS HIPS and SIPS 9.0 to create 2D and 3D bathymetric and backscatter intensity surfaces with a resolution of 1 m. The offshore study site is part of the 286 Ma western Variscian orogenic front and has several massive outcrops, exhibiting 5 to 20 m of near-vertical relief. These outcrops were structurally mapped and relatively aged, and exhibit significant folding, rotation, tilting, and joint systems. Google Earth, ArcGIS, and previous terrestrial studies were used to further analyze how geomorphology is controlled by seafloor composition and structural features. Rock type and age were interpreted by comparing fracture analysis of the joints and fold trends to similar onshore outcrops documented previously, to determine an age of 416-299 Ma for the shelf's outcropping strata and associated structural features. The oldest features observed are regional anticlines and synclines containing Upper Devonian Old Red Sandstone and Lower Carboniferous shales. Within the shale layers are NE-SW plunging parasitic chevron folds. Jointing is observed in both sandstone and shale layers and is superimposed on chevron folding, with cross joints appearing to influence shallow current patterns. Rotation of the regional folds is the youngest structural feature, as both the parasitic folds and joint systems are warped. Our study shows that high resolution sonar is an effective tool for offshore structural mapping and is an important resource for understanding the geomorphology and geologic history of submerged outcrops on continental shelf systems.

  11. Caracterización de agregaciones de merluza de cola (Macruronus magellanicus en la zona centro-sur de Chile Characterization of Chilean hoki (Macruronus magellanicus aggregations off central-southern Chile

    Directory of Open Access Journals (Sweden)

    Dante Queirolo

    2008-01-01

    Full Text Available Se realizó la caracterización mensual de las agregaciones de merluza de cola usando registros acústicos obtenidos por equipos SIMRAD EK60 y ES60 a bordo de tres embarcaciones multipropósito que operaron en la Unidad de Pesquería Centro-Sur durante el año 2003, para lo cual se emplearon descriptores morfológicos y batimétricos. En cuanto a su morfología, las agregaciones mostraron una amplia variabilidad, explicada por su nivel de cohesión y tendencia a formar agregaciones de gran extensión horizontal, mientras que batimétricamente se determinó que el 90% de éstas se ubicaron preferentemente entre 300 y 450 m. Existe evidencia de asociación entre diversos descriptores y estos a su vez con otros factores como talla media, temperatura del agua, latitud y mes, lo que permite describir apropiadamente la forma de las agregaciones y su ubicación en la columna de agua. Algunas relaciones relevantes corresponden a: profundidad de las agregaciones respecto a la profundidad del fondo (r = 0,55, altitud de las agregaciones respecto a la profundidad del fondo (r = 0,72, altitud de las agregaciones respecto al índice de profundidad relativa (r = -0,98 y profundidad de las agregaciones respecto a la talla media (r = 0,66.A monthly characterization of Chilean hoki aggregations was done using acoustic records ob-tained with SIMRAD EK60 and ES60 devices aboard three multipurpose vessels that operated in the central-southern fishery unit during 2003; this considered morphological and bathymetric descriptors. The wide mor-phological variation of the aggregations was explained by their cohesión level and tendency to form large horizontal aggregations whereas, bathymetrically, 90% of the aggregations were located between 300 and 450 m. Evidence of associations between various descriptors was found, and these were, in turn, associated with other factors such as mean size, water temperature, latitude, and month, allowing an adequate description of the

  12. High-resolution Digital Mapping of Historical Lava Flows as a Test-bed for Lava Flow Models

    Science.gov (United States)

    Pyle, D. M.; Parks, M.; Nomikou, P.; Mather, T. A.; Simou, E.; Kalnins, L. M.; Paulatto, M.; Watts, A. B.

    2013-12-01

    Quantitative analysis of high-resolution lava flow morphology can improve our understanding of past effusive eruptions by providing insight into eruptive processes and the rheological properties of erupted magmas. We report the results of an ongoing investigation into the young dacite lava flows of the Kameni islands, Santorini volcano, Greece, which were emplaced during both subaerial and shallow submarine eruptions over the past 3000 years. Historical eruptions of the Kameni islands since 1866 have been very carefully documented in contemporaneous scientific reports. Eruptions since 1573 appear to be time-predictable, with a close relationship between eruption length, the size of extruded lava domes, and the time elapsed since the previous eruption. A new NERC - Airborne Survey and Research Facility LiDAR survey of the Kameni islands was completed in May 2012, using a Leica ALS50 Airborne Laser Scanner mounted on a Dornier 228 aircraft. The topographic surface was mapped at an average point density of 2.1 points per square metre, and covers the entire extent of the youngest subaerial lava flow fields on Santorini. A 2-m DEM derived from the 2012 LiDAR dataset was merged with a 5-m resolution bathymetric grid, based on multibeam surveys carried out by the Hellenic Centre for Marine Research, during cruises in 2001 and 2006, using a SEABEAM 2120 hull-mounted swath system. The resultant grid provides the first high resolution map of both subaerial and submarine historic lava flows emplaced in the centre of the Santorini caldera, and includes several previously unidentified submarine flows and cones. Attribute maps were used to delineate and identify discrete lava flows both onshore and offshore; and morphometric profiles were used to compute accurate volumetric estimates for each of the historic flows, and to determine bulk rheological properties of the lavas, assuming a Bingham rheology. This ongoing work will improve our analysis of the relationship between

  13. Quantifying Methane Flux from a Prominent Seafloor Crater with Water Column Imagery Filtering and Bubble Quantification Techniques

    Science.gov (United States)

    Mitchell, G. A.; Gharib, J. J.; Doolittle, D. F.

    2015-12-01

    Methane gas flux from the seafloor to atmosphere is an important variable for global carbon cycle and climate models, yet is poorly constrained. Methodologies used to estimate seafloor gas flux commonly employ a combination of acoustic and optical techniques. These techniques often use hull-mounted multibeam echosounders (MBES) to quickly ensonify large volumes of the water column for acoustic backscatter anomalies indicative of gas bubble plumes. Detection of these water column anomalies with a MBES provides information on the lateral distribution of the plumes, the midwater dimensions of the plumes, and their positions on the seafloor. Seafloor plume locations are targeted for visual investigations using a remotely operated vehicle (ROV) to determine bubble emission rates, venting behaviors, bubble sizes, and ascent velocities. Once these variables are measured in-situ, an extrapolation of gas flux is made over the survey area using the number of remotely-mapped flares. This methodology was applied to a geophysical survey conducted in 2013 over a large seafloor crater that developed in response to an oil well blowout in 1983 offshore Papua New Guinea. The site was investigated by multibeam and sidescan mapping, sub-bottom profiling, 2-D high-resolution multi-channel seismic reflection, and ROV video and coring operations. Numerous water column plumes were detected in the data suggesting vigorously active vents within and near the seafloor crater (Figure 1). This study uses dual-frequency MBES datasets (Reson 7125, 200/400 kHz) and ROV video imagery of the active hydrocarbon seeps to estimate total gas flux from the crater. Plumes of bubbles were extracted from the water column data using threshold filtering techniques. Analysis of video images of the seep emission sites within the crater provided estimates on bubble size, expulsion frequency, and ascent velocity. The average gas flux characteristics made from ROV video observations is extrapolated over the number

  14. Morphology, structure, composition and build-up processes of the active channel-mouth lobe complex of the Congo deep-sea fan with inputs from remotely operated underwater vehicle (ROV) multibeam and video surveys

    Science.gov (United States)

    Dennielou, Bernard; Droz, Laurence; Babonneau, Nathalie; Jacq, Céline; Bonnel, Cédric; Picot, Marie; Le Saout, Morgane; Saout, Yohan; Bez, Martine; Savoye, Bruno; Olu, Karine; Rabouille, Christophe

    2017-08-01

    The detailed structure and composition of turbiditic channel-mouth lobes is still largely unknown because they commonly lie at abyssal water depths, are very thin and are therefore beyond the resolution of hull-mound acoustic tools. The morphology, structure and composition of the Congo turbiditic channel-mouth lobe complex (90×40 km; 2525 km2) were investigated with hull-mounted swath bathymetry, air gun seismics, 3.5 kHz sub-bottom profiler, sediment piston cores and also with high-resolution multibeam bathymetry and video acquired with a Remote Operating Vehicle (ROV). The lobe complex lies 760 km off the Congo River mouth in the Angola abyssal plain between 4740 and 5030 m deep. It is active and is fed by turbidity currents that deposit several centimetres of sediment per century. The lobe complex is subdivided into five lobes that have prograded. The lobes are dominantly muddy. Sand represents ca. 13% of the deposits and is restricted to the feeding channel and distributaries. The overall lobe body is composed of thin muddy to silty turbidites. The whole lobe complex is characterized by in situ mass wasting (slumps, debrites). The 1-m-resolution bathymetry shows pervasive slidings and block avalanches on the edges of the feeding channel and the channel mouth indicating that sliding occurs early and continuously in the lobe build-up. Mass wasting is interpreted as a consequence of very-high accumulation rates, over-steepening and erosion along the channels and is therefore an intrinsic process of lobe building. The bifurcation of feeding channels is probably triggered when the gradient in the distributaries at the top of a lobe becomes flat and when turbidity currents find their way on the higher gradient on the lobe side. It may also be triggered by mass wasting on the lobe side. When a new lobe develops, the abandoned lobes continue to collect significant turbiditic deposits from the feeding channel spillover, so that the whole lobe complex remains active. A

  15. Latest Pleistocene Sediment Wedge on the New Jersey Outer Continental Shelf - Forced Regressive Paleo-Hudson Delta?

    Science.gov (United States)

    Santra, M.; Goff, J. A.; Steel, R. J.

    2011-12-01

    The offlapping sediment wedge on the outer shelf off New Jersey that overlies the regional reflector R-horizon shows many of the characteristic features of a progradational succession deposited during falling sea level (forced regression). This interpretation is consistent with the estimated latest Pleistocene age of the wedge - a well-established period of large-scale eustatic sea level fall. The sediment wedge occupies the outer shelf of New Jersey south of the Hudson Shelf Valley, extending down to the shelf edge. The sediment wedge appears to be strongly strike-oriented. The absence of any record of time-equivalent fluvial/distributary channels on the proximal part of the sediment wedge led some previous workers to the interpretation that the wedge was a product of redistribution of sediment on the shelf rather than a deltaic feature supplied by a fluvial source. The absence of fluvial and coastal plain deposits capping the proximal end of the wedge is actually a characteristic feature of forced regressive deposits and does not preclude a fluvial source for the sediments constituting the wedge. Reinterpretation of high-resolution (1-12 kHz), deep-towed and hull-mounted CHIRP seismic data collected on the New Jersey outer shelf in 2001, 2002 and 2006 shows possible terminal distributary channel deposits and mass transport deposits preserved in the distal part of the wedge that have not been described previously. These channel-like features are restricted in their distribution and their preservation in the sedimentary record is possibly due to punctuated sea-level rise within the overall falling trajectory of sea level that preceded the last glacial maximum (LGM). The presence of these channels and the mass transport complexes point to a direct fluvial feeder, which supplied the sediments to build the sediment wedge on New Jersey outer continental shelf. Detailed mapping of the sediment wedge using the CHIRP data shows that the sediment wedge is composed of

  16. Evidence of Diel Vertical Migration of Mesopelagic Sound-Scattering Organisms in the Arctic

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    Harald Gjøsæter

    2017-10-01

    Full Text Available While sound scattering layers (SSLs have been described previously from ice-covered waters in the Arctic, the existence of a viable mesopelagic community that also includes mesopelagic fishes in the Arctic has been questioned. In addition, it has been hypothesized that vertical migration would hardly exist in these areas. We wanted to check if deep scattering layers (DSLs was found to the west and north of Svalbard (79°30′N−82°10′N during autumn 2015, and if present; whether organisms in such DSLs undertook vertical migrations. Our null hypothesis was that there would be no evidence of diel vertical migration. Multi-frequency acoustic observations by hull mounted echo sounder (18, 38, and 120 kHz revealed a DSL at depths ~210–510 m in areas with bottom depths exceeding ~600 m. Investigating eight geographical locations that differed with respect to time periods, light cycle and sea ice conditions, we show that the deeper layer of DSL displayed a clear ascending movement during night time and a descending movement during daytime. The high-light weighted mean depth (WMD (343–514 m with respect to backscattered energy was statistically deeper than the low-light WMD (179–437 m for the locations studied. This behavior of the DSL was found to be consistent both when the sun was continuously above the horizon and after it started to set on 1 September, and both in open water and sea ice covered waters. The WMD showed an increasing trend, while the nautical area backscattering strength from the DSL showed a decreasing trend from south to north among the studied locations. Hydrographic observations revealed that the diel migration was found in the lower part of the north-flowing Atlantic Water, and was disconnected from the surface water masses above the Atlantic Water during day and night. The organisms conducting vertical migrations were studied by vertical and oblique hauls with zooplankton nets and pelagic trawls. These data suggest

  17. Digital bedrock mapping at the Geological Survey of Norway: BGS SIGMA tool and in-house database structure

    Science.gov (United States)

    Gasser, Deta; Viola, Giulio; Bingen, Bernard

    2016-04-01

    Since 2010, the Geological Survey of Norway has been implementing and continuously developing a digital workflow for geological bedrock mapping in Norway, from fieldwork to final product. Our workflow is based on the ESRI ArcGIS platform, and we use rugged Windows computers in the field. Three different hardware solutions have been tested over the past 5 years (2010-2015). (1) Panasonic Toughbook CE-19 (2.3 kg), (2) Panasonic Toughbook CF H2 Field (1.6 kg) and (3) Motion MC F5t tablet (1.5 kg). For collection of point observations in the field we mainly use the SIGMA Mobile application in ESRI ArcGIS developed by the British Geological Survey, which allows the mappers to store georeferenced comments, structural measurements, sample information, photographs, sketches, log information etc. in a Microsoft Access database. The application is freely downloadable from the BGS websites. For line- and polygon work we use our in-house database, which is currently under revision. Our line database consists of three feature classes: (1) bedrock boundaries, (2) bedrock lineaments, and (3) bedrock lines, with each feature class having up to 24 different attribute fields. Our polygon database consists of one feature class with 38 attribute fields enabling to store various information concerning lithology, stratigraphic order, age, metamorphic grade and tectonic subdivision. The polygon and line databases are coupled via topology in ESRI ArcGIS, which allows us to edit them simultaneously. This approach has been applied in two large-scale 1:50 000 bedrock mapping projects, one in the Kongsberg domain of the Sveconorwegian orogen, and the other in the greater Trondheim area (Orkanger) in the Caledonian belt. The mapping projects combined collection of high-resolution geophysical data, digital acquisition of field data, and collection of geochronological, geochemical and petrological data. During the Kongsberg project, some 25000 field observation points were collected by eight

  18. Evolution of the Sedimentary Basin Within the Eastern Eez Polygon at the Gulf of Mexico

    Science.gov (United States)

    Valle, S.; Mortera-Gutierrez, C. A.; Bandy, W. L.; Escobar-Briones, E. G.; Perez, D. A.

    2013-05-01

    This study shows the seafloor structures and magnetic anomalies inside the eastern EEZ polygon at the Gulf of Mexico. The objective of this study is to examine the previous hypothesis of the Gulf of Mexico opening, based on the seafloor magnetic character. Researchers from the "Instituto de Ciencias del Mar y Limnología" at UNAM, collected , multibeam bathymetric data, high-resolution seismic reflection and magnetic profiles along 37 E-W transects during two campaigns on board the UNAM vessel, BO JUSTO SIERRA, SIGSBEE-11 in 2008 and SIGSBEE-13 in 2010. Results of the bathymetry data gathered with the EM300 multibeam echo sounder (Kongsberg) and processed with the software Caraibes from IFREMER has generated a bathymetry chart of seafloor at the Eastern Polygon, and a mosaic of back-scattering images. The high-resolution seismic profiles gathered with the subbottom profiler TOPAS PS-18 (Kongsberg) provide information on the stratigraphy sediment packages across this polygon and across the deep Mississippi Canyon. The magnetic anomalies are reduced from the data gathered with a proton-precession magnetometer, G877 (GEOMETRICS). The anomalies are modeled, based on a N_S rift at the Gulf central sector. The bathymetric chart and reflectivity mosaics of SIGSBEE-11 and SIGSBEE-13 documented the smooth relief of the seabed slope toward the Gulf central sector and abrupt morphological features associated to the meanders of the Mississippi Canyon that trend to the East. The multibeam bathymetry chart shows a relief depth that goes from 2,900 to 3,400 m from north to south. Meanders are observed in the seabed within the Eastern Polygon which is related to turbidity currents from the Mississippi River, and having a trend from west to east. The relief of the canyon shows channels with widths between 400 and 1800 m, and canyon depths up to 80 m. The high-resolution seismic sections, show well defined stratigraphy packages, where clear sediment strata are interrupted by

  19. Thickness characterisation of oil spills using active microwave sensors

    Science.gov (United States)

    True, Michael; Shuchman, Robert A.; Kletzli, D. W., Jr.; Johannessen, Johnny A.; Digranes, Gunar; Berg, Sverre; Dalland, Kjell

    1994-12-01

    Oil thickness is a crucial parameter in the characterization of oil spills for environmental impact. The feasibility of using active microwave sensors to measure thickness was addressed in a series of microwave scatterometer experiments performed by Simrad Marine A/S in a wave tank at the Nansen Environmental Remote Sensing Center. The thickness of the oil layer was maintained at levels similar to the thick part of an oil spill (0.1 - 1 mm). The measurements showed the capability of active microwave sensors to measure oil spill thickness when the oil type is known. In addition to thickness characterization, the experiment studied the effects of oil viscosity, incidence angle, wind speed, wind angle, microwave frequency, and polarization. The backscatter contrast was observed to be greater for lower incidence angles which indicates that the ERS-1 viewing geometry is optimum for the detection and measurement of thick oil slicks. A thickness-dependent backscatter model was developed which included the effects of oil viscosity, composite surface effects, and oil-water reflectivities. The model viscous effects saturated when the oil thickness was greater than the viscous boundary layer thickness. This explained the observed C-VV backscatter contrast saturation for low viscosity diesel oil at thicknesses greater than 0.15 mm. The model predicted contrast saturation at greater thicknesses for the higher viscosity oils. The data showed this trend but the measurements did not extend to thicknesses which tested the model completely.

  20. Seasonal and diel effects on acoustic fish biomass estimates: application to a shallow reservoir with untargeted common carp (Cyprinus carpio)

    Science.gov (United States)

    Djemali, Imed; Yule, Daniel; Guillard, Jean

    2016-01-01

    The aim of the present study was to understand how seasonal fish distributions affect acoustically derived fish biomass estimates in a shallow reservoir in a semi-arid country (Tunisia). To that end, sampling events were performed during four seasons (spring (June), summer (September), autumn (December) and winter (March)) that included day and night surveys. A Simrad EK60 echosounder, equipped with two 120-kHz split-beam transducers for simultaneous horizontal and vertical beaming, was used to sample the entire water column. Surveys during spring and summer and daytime hours of winter were deemed unusable owing to high methane flux from the sediment, and during the day survey of autumn, fish were close to the reservoir bottom leading to low detectability. It follows that acoustic surveys should be conducted only at night during the cold season (December–March) for shallow reservoirs having carp Cyprinus carpio (L.) as the dominant species. Further, night-time biomass estimates during the cold season declined significantly (P night-time survey, overall fish biomass in the Bir-Mcherga Reservoir was high (mean (± s.d.) 185 ± 98 tonnes (Mg)), but annual fishery exploitation is low (19.3–24.1 Mg) because the fish biomass is likely dominated by invasive carp not targeted by fishers. The results suggest that controlling carp would help improve the fishery.

  1. Analysis of calibrated seafloor backscatter for habitat classification methodology and case study of 158 spots in the Bay of Biscay and Celtic Sea

    Science.gov (United States)

    Fezzani, Ridha; Berger, Laurent

    2018-01-01

    An automated signal-based method was developed in order to analyse the seafloor backscatter data logged by calibrated multibeam echosounder. The processing consists first in the clustering of each survey sub-area into a small number of homogeneous sediment types, based on the backscatter average level at one or several incidence angles. Second, it uses their local average angular response to extract discriminant descriptors, obtained by fitting the field data to the Generic Seafloor Acoustic Backscatter parametric model. Third, the descriptors are used for seafloor type classification. The method was tested on the multi-year data recorded by a calibrated 90-kHz Simrad ME70 multibeam sonar operated in the Bay of Biscay, France and Celtic Sea, Ireland. It was applied for seafloor-type classification into 12 classes, to a dataset of 158 spots surveyed for demersal and benthic fauna study and monitoring. Qualitative analyses and classified clusters using extracted parameters show a good discriminatory potential, indicating the robustness of this approach.

  2. Beaked whales demonstrate a marked acoustic response to the use of shipboard echosounders.

    Science.gov (United States)

    Cholewiak, Danielle; DeAngelis, Annamaria I; Palka, Debra; Corkeron, Peter J; Van Parijs, Sofie M

    2017-12-01

    The use of commercial echosounders for scientific and industrial purposes is steadily increasing. In addition to traditional navigational and fisheries uses, commercial sonars are used extensively for oceanographic research, benthic habitat mapping, geophysical exploration, and ecosystem studies. Little is known about the effects of these acoustic sources on marine animals, though several studies have already demonstrated behavioural responses of cetaceans to shipboard echosounders. Some species of cetaceans are known to be particularly sensitive to acoustic disturbance, including beaked whales. In 2011 and 2013, we conducted cetacean assessment surveys in the western North Atlantic in which a suite of Simrad EK60 echosounders was used to characterize the distribution of prey along survey tracklines. Echosounders were alternated daily between active and passive mode, to determine whether their use affected visual and acoustic detection rates of beaked whales. A total of 256 groups of beaked whales were sighted, and 118 definitive acoustic detections were recorded. Regression analyses using generalized linear models (GLM) found that sea state and region were primary factors in determining visual sighting rates, while echosounder state was the primary driver for acoustic detections, with significantly fewer detections (only 3%) occurring when echosounders were active. These results indicate that beaked whales both detect and change their behaviour in response to commercial echosounders. The mechanism of this response is unknown, but could indicate interruption of foraging activity or vessel avoidance, with potential implications for management and mitigation of anthropogenic impacts.

  3. Hawaiian spinner dolphins aggregate midwater food resources through cooperative foraging

    Science.gov (United States)

    Benoit-Bird, Kelly; Au, Whitlow

    2003-10-01

    To test the hypothesis that spinner dolphins in Hawaii may actively aggregate their prey through cooperative foraging, a 200-kHz multi-beam sonar (Simrad MS2000) was used to observe 323 groups of spinner dolphins foraging within a midwater, micronekton sound-scattering layer off Oahu. Strong cooperation was observed in groups of 8-14 pairs of spinner dolphins. The dolphin group size was highest at midnight when the density of prey was highest and was significantly higher in Makua Beach, where the prey density was higher, than Electric Beach, where the prey density was lower. Cooperative groups of dolphins aggregated their food resources, apparently using their preys' avoidance behavior to create distinct, high-density patches in the prey. Prey aggregation was strongly stereo-typed, regardless of the distribution of the scattering layer. Dolphins swam around the edge of a 28-40 m diameter circle at least 5 times, concentrating prey within this area before pairs of dolphins on opposite sides of the circle swapped positions in the circle, swimming through the high density prey 'donut' they had formed. The hypothesis that nocturnal animals aggregate prey in midwater could not have been tested without the three-dimensional information on prey distribution and dolphin geometry provided by the multi-beam.

  4. Introducing universal ultrasound screening for developmental dysplasia of the hip doubled the treatment rate.

    Science.gov (United States)

    Olsen, Stine F; Blom, Hans C; Rosendahl, Karen

    2018-02-01

    There is no evidence on the effect of universal ultrasound screening on developmental dysplasia of the hip. We examined the impact of adding an ultrasound examination to a one examiner clinical screening strategy on treatment, follow-up rates and the number of cases detected late in a low-prevalence population. All eligible babies born at Kongsberg Hospital, Norway, from 1998 to 2006 (n = 4245) underwent both clinical and ultrasound hip examinations within three days of life. Indications for immediate treatment were positive Barlow or Ortolani manoeuvres and, or, sonographic dysplasia. Sonographic immature hips were followed until normalisation. Treatment rates and rates from the 1989 to 1997 prestudy period (n = 3594), including late diagnoses, were collected from hospital records. Treatment was initiated in 90 (2.1%) infants (74 girls), 63 (70%) from birth, compared to 33 (0.9%) during the prestudy period. The follow-up rate did not change (11%). There were two (0.5/1000) and four (1.0/1000) cases detected late, respectively. No one underwent surgery during the first year of life and no avascular necrosis was seen. Adding universal ultrasound to clinical screening performed by the same, experienced paediatrician doubled the treatment rate, without influencing the already low numbers of late cases. ©2017 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  5. Geomorphology of the Southwest Coast of County Cork, Ireland: A Look into the Rocks, Folds, and Glacial Scours

    Science.gov (United States)

    Bowden, S.; Wireman, R.; Sautter, L.; Beutel, E. K.

    2015-12-01

    Bathymetric data were collected off the southwest coast of County Cork, Ireland by the joint INFOMAR project between the Marine Institute of Ireland and the Geologic Survey of Ireland. Data were collected using a Kongsberg EM2040 multibeam sonar on the R/V Celtic Voyager, in August and September 2014, and were post-processed with CARIS HIPS and SIPS 8.1 and 9.0 software to create 2D and 3D bathymetric surfaces. From the computer generated images, some of the lithologic formations were relatively aged and observed. The studied regions range in depth from 20 to 118 m, with shallower areas to the northeast. Several large rock outcrops occur, the larger of which shows a vertical rise of nearly 20 m. These outcrops are oriented in a northeast-southwest direction, and exhibit significant bed folding, regional folding, tilted beds, and cross joints. The folds studied are plunging chevron folds. These folds have a northeast-southwest fold axis orthogonal to the cross joints and are older relative to the jointing systems. The NE-SW joints are older than the NW-SE joints due to their correlation with drainage and erosion patterns. Regional folding is the youngest feature due to its superposition on the chevron folding and jointing systems. The interaction of cross jointing and folding is consistent with the geologic history of the area, and creates a unique bathymetry worthy of further study.

  6. Improved detection and mapping of deepwater hydrocarbon seeps: optimizing multibeam echosounder seafloor backscatter acquisition and processing techniques

    Science.gov (United States)

    Mitchell, Garrett A.; Orange, Daniel L.; Gharib, Jamshid J.; Kennedy, Paul

    2018-02-01

    Marine seep hunting surveys are a current focus of hydrocarbon exploration surveys due to recent advances in offshore geophysical surveying, geochemical sampling, and analytical technologies. Hydrocarbon seeps are ephemeral, small, discrete, and therefore difficult to sample on the deep seafloor. Multibeam echosounders are an efficient seafloor exploration tool to remotely locate and map seep features. Geophysical signatures from hydrocarbon seeps are acoustically-evident in bathymetric, seafloor backscatter, midwater backscatter datasets. Interpretation of these signatures in backscatter datasets is a fundamental component of commercial seep hunting campaigns. Degradation of backscatter datasets resulting from environmental, geometric, and system noise can interfere with the detection and delineation of seeps. We present a relative backscatter intensity normalization method and an oversampling acquisition technique that can improve the geological resolvability of hydrocarbon seeps. We use Green Canyon (GC) Block 600 in the Northern Gulf of Mexico as a seep calibration site for a Kongsberg EM302 30 kHz MBES prior to the start of the Gigante seep hunting program to analyze these techniques. At GC600, we evaluate the results of a backscatter intensity normalization, assess the effectiveness of 2X seafloor coverage in resolving seep-related features in backscatter data, and determine the off-nadir detection limits of bubble plumes using the EM302. Incorporating these techniques into seep hunting surveys can improve the detectability and sampling of seafloor seeps.

  7. Reducing uncertainty and bias in acoustic biomass estimations of southern blue whiting (Micromesistius australis in the southeastern Pacific: transducer motion effects upon acoustic attenuation Reduciendo el sesgo e incertidumbre de las estimaciones hidroacústicas de biomasa de merluza de tres aletas (Micromesistius australis en el Pacífico suroriental: efectos del movimiento del transductor sobre la atenuación acústica

    Directory of Open Access Journals (Sweden)

    Alvaro Saavedra

    2012-09-01

    Full Text Available We evaluated the loss of sensitivity due to the motion experienced by a hull-mounted transducer and its effects upon the estimated biomass of southern blue whiting (Micromesistius australis in an acoustic survey conducted in the southeastern Pacific, off the Chilean coast, during the austral winter of 2009. Vessel motion data (pitch and roll were registered in situ using a digital clinometer and used to correct the nautical area scattering coefficients (NASC in elementary sampling units of 926 m distance by 10 m depth. These NASC correction factors (NASCcp were calculated using Dunford's algorithm for circular transducers. We found high variability in NASCcp, which averaged 12%, and ranged between 0 and 50%. NASCcp variability was explained significantly by the mean depth of the integrated stratum (33%, the weather condition, as measured by Beaufort's scale (5%, and the vessel course relative to wind direction (2%. The empirical model we used to explain NASC Cp variability may be suitable for correcting bias due to transducer motion in other, past and future, fisheries acoustic surveys targeting mid-water species under rough weather conditions.Se evaluó la pérdida de sensibilidad producida por el movimiento de un transductor montado en el casco y sus efectos sobre la abundancia y biomasa estimada de merluza de tres aletas (Micromesistius australis en un estudio acústico realizado en el Pacífico suroriental, frente a la costa de Chile, durante el invierno austral de 2009. Los datos de movimiento del barco (cabeceo y balanceo fueron registrados in situ utilizando un clinómetro digital y luego utilizados para estimar la pérdida teórica de sensibilidad del transductor y, finalmente, traducir esta pérdida en factores de corrección del coeficiente de dispersión por área náutica (NASC calculados para intervalos básicos de muestreo de 926 m de distancia por 10 m de profundidad. Los factores de corrección del NASC (NASC Cp fueron calculados

  8. Seafloor Characterisation of the Gakkel Ridge using Multibeam Sonar, Backscatter and Sidescan Data

    Science.gov (United States)

    Hatzky, J.; Schenke, H. W.

    2003-04-01

    The Gakkel Ridge in the Arctic Ocean was the object of the Arctic Mid-Ocean Ridge Expedition (AMORE) which was carried out by the research icebreakers R/V "Polarstern" (Germany) and USCGC "Healy" (USA) in the boreal summer 2001. This largely unexplored mid-ocean ridge (MOR) is of particular scientific interest due to its volcanic activity and tectonic structure. With spreading rates of 13mm/a in the western and 6 mm/a in the eastern part Gakkel Ridge is the slowest spreading MOR on earth (Michael et al., 2001). The surveyed area which is situated between 82°N / 8°W and 87°N / 75°E has a length of 8890 km and a varying width from 18 to 46 km. The range of measured depths reaches from 566 m on the top of a huge seamount to 5673 m in the central rift valley. Prominent underwater features of remarkable morphologic diversity (e.g. small volcanoes embedded in massive ridge flanks) were discovered in this region. One of the most important goals of the expedition was the compilation of a high resolution grid which serves as basis for a three dimensional digital terrain model (DTM), the derivation of contour lines and the production of bathymetric maps. Accordingly, two hull-mounted multibeam sonars were used for the depth data acquisition: the "Hydrosweep DS-2" system onboard "Polarstern" and the "Seabeam 2112" system onboard "Healy". In order to calculate a combined grid out of two independent data sets different technical specifications of both sonar systems (e.g. frequency, opening angle, number of beams, accuracy) had to be taken into account. Dense sea ice cover made the sonar measurements difficult. Thick floes caused hydroacoustic disturbances that heavily debased the data quality. Outliers and blunders of depths and navigation data had to be corrected in a drawn-out post-processing by appropriate software tools. Both echo sounding systems recorded backscatter information and sidescan data during the entire cruise. Onboard "Polarstern" the sub-bottom profiling

  9. New Mapping of Mariana Submarine Volcanoes with Sidescan and Multibeam Sonars

    Science.gov (United States)

    Embley, R. W.; Chadwick, W. W.; Baker, E. T.; Johnson, P. D.; Merle, S. G.; Ristau, S.

    2003-12-01

    An expedition in February/March 2003 on the R/V Thomas G. Thompson mapped more than 18,000 km2 with the towed MR1 sidescan sonar and almost 28,000 km2 with an EM300 hull-mounted multibeam system along the Mariana volcanic arc. The expedition was funded by NOAA's Office of Ocean Exploration (more on the expedition can be found at: http://oceanexplorer.noaa.gov/explorations/03fire/welcome.html). The MR1 sidescan surveys began at the northern end of a 2001 R/V Melville MR1 survey at 16§ N and extended to Nikko Volcano at 23\\deg 05'N. A portion of the southern back-arc spreading center and the arc volcanoes south of 16\\deg N were mapped using the EM300 system. Of 43 submarine arc volcanoes surveyed that have basal diameters of 10 km or greater, 17 have summit calderas or craters. Of these, however, only 5 have diameters more than 2 km. In an accompanying survey of hydrothermal activity along the arc, CTD casts and/or tows were conducted over more than 50 individual volcanoes. The 11 volcanoes with active hydrothermal systems found in the course of these surveys appear to be about equally divided between those with and without summit calderas or craters (for additional information, see Baker et al., Resing et al., and Lupton et al., this session). The flanks of the submarine volcanoes and islands of the central and northern Mariana Arc consist largely of volcaniclastic flows. Most of the larger edifices have high-backscatter spoke-like patterns that probably represent coarser and/or younger flows from the summits. Higher relief high-backscatter areas, also commonly exhibiting a radial pattern, are found on many of the volcanoes' flanks. These are probably lava flows erupted along radial fissures. The Mariana Arc volcanoes are shedding large volumes of volcaniclastic material westward into the back-arc basin through a series of deep-sea channels oriented transverse to the arc that are in many places fed by flows from several volcanoes. On many of the volcaniclastic

  10. Sea Education Association's sailing research vessels as innovative platforms for long-term research and education

    Science.gov (United States)

    Joyce, P.; Carruthers, E. A.; Engels, M.; Goodwin, D.; Lavender Law, K. L.; Lea, C.; Schell, J.; Siuda, A.; Witting, J.; Zettler, E.

    2012-12-01

    Sea Education Association's (SEA) two research vessels, the SSV Corwith Cramer and the SSV Robert C. Seamans are unique in the research world. Not only do these ships perform advanced research using state of the art equipment, they do so under sail with high school, undergraduate, and graduate students serving as both the science team and the crew. Because of SEA's educational mission and reliance on prevailing winds for sailing, the vessels have been studying repeated tracks for decades, providing valuable long-term data sets while educating future marine scientists. The Corwith Cramer has been collecting data in the North Atlantic between New England, the Sargasso Sea, Bermuda, and the Caribbean since 1987 while the Robert C. Seamans has been operating in the Eastern Pacific between the US West Coast, Hawaii, and French Polynesia since 2001. The ships collect continuous electronic data from hull mounted ADCP, chirp, and a clean flowing seawater system logging temperature, salinity, in-vivo chlorophyll and CDOM fluorescence, and beam attenuation. The ships also periodically collect data from profiling CTDs with chlorophyll and CDOM fluorometers, transmissometers, and dissolved oxygen and PAR sensors. In addition to electronic data, archived long term data sets include physical samples from net tows such as marine plastic debris and tar, and plankton including Halobates (a marine insect), leptocephali (eel larvae), and phyllosoma (spiny lobster larvae). Both vessels are 134' brigantine rig tall ships and are designated sailing school vessels (SSV) by the US Coast Guard, and both have received instrumentation grants from NSF to provide high quality, reliable data that is submitted to the NSF R2R archives. Students sailing on these ships spend time on shore at the SEA campus in Woods Hole, MA taking classes in oceanography, nautical science, maritime studies and public policy. Each student is required to write a proposal for their research before heading to sea, and

  11. Passive acoustic records of two vigorous bubble-plume methane seeps on the Oregon continental margin

    Science.gov (United States)

    Dziak, R. P.; Matsumoto, H.; Merle, S. G.; Embley, R. W.; Baumberger, T.; Hammond, S. R.

    2016-12-01

    We present preliminary analysis of the acoustic records of two bubble-plume methane seeps recorded by an autonomous hydrophone deployed during the E/V Nautilus expedition (NA072) in June 2016. The goal of the NA072 expedition was to use the Simrad 302 as a survey tool to map bubble plumes at a regional scale along the Oregon and northern California margins, followed by in situ investigation of bubble-plume sites using the ROV Hercules. The exploration carried out during NA072 resulted in the discovery of hundreds of new individual methane seep sites in water depths ranging from 125 to 1725 m depth. A Greenridge Acousonde 3B™ hydrophone was deployed via ROV within two vigorous bubble-plume sites. Despite persistent ship and ROV propeller noise, the acoustic signature of the bubble-plume can be seen in the hydrophone record as a broadband (0.5 - 4.5 kHz) series of short duration ( 0.2-0.5 msec) pulses that occur in clusters of dozens of pulses lasting 2-3 secs. Previous studies of the passive acoustics of seep bubble-plumes indicate sound is generated during bubble formation, where detachment of the gas bubble from the end of a tube or conduit causes the bubble to oscillate, producing sound. The peak frequency f (the zeroth oscillatory mode) and the bubble equivalent spherical radius r for a given pressure P are: f = (2πr)-1 [(3γP/ρ)]1/2 where γ is the ratio of gas specific heat at constant pressure to constant volume and ρ is the water density (Leifer and Tang, 2006). Thus the frequency of a bubble's oscillation is proportional to the bubble's volume, and therefore it may be possible to use our acoustic data to obtain an estimate of the volume of methane being released at these seafloor plume sites.

  12. Do top predators cue on sound production by mesopelagic prey?

    Science.gov (United States)

    Baumann-Pickering, S.; Checkley, D. M., Jr.; Demer, D. A.

    2016-02-01

    Deep-scattering layer (DSL) organisms, comprising a variety of mesopelagic fishes, and squids, siphonophores, crustaceans, and other invertebrates, are preferred prey for numerous large marine predators, e.g. cetaceans, seabirds, and fishes. Some of the DSL species migrate from depth during daylight to feed near the surface at night, transitioning during dusk and dawn. We investigated if any DSL organisms create sound, particularly during the crepuscular periods. Over several nights in summer 2015, underwater sound was recorded in the San Diego Trough using a high-frequency acoustic recording package (HARP, 10 Hz to 100 kHz), suspended from a drifting surface float. Acoustic backscatter from the DSL was monitored nearby using a calibrated multiple-frequency (38, 70, 120, and 200 kHz) split-beam echosounder (Simrad EK60) on a small boat. DSL organisms produced sound, between 300 and 1000 Hz, and the received levels were highest when the animals migrated past the recorder during ascent and descent. The DSL are globally present, so the observed acoustic phenomenon, if also ubiquitous, has wide-reaching implications. Sound travels farther than light or chemicals and thus can be sensed at greater distances by predators, prey, and mates. If sound is a characteristic feature of pelagic ecosystems, it likely plays a role in predator-prey relationships and overall ecosystem dynamics. Our new finding inspires numerous questions such as: Which, how, and why have DSL organisms evolved to create sound, for what do they use it and under what circumstances? Is sound production by DSL organisms truly ubiquitous, or does it depend on the local environment and species composition? How may sound production and perception be adapted to a changing environment? Do predators react to changes in sound? Can sound be used to quantify the composition of mixed-species assemblages, component densities and abundances, and hence be used in stock assessment or predictive modeling?

  13. Vertical distribution and diel vertical migration of krill beneath snow-covered ice and in ice-free waters

    KAUST Repository

    Vestheim, Hege

    2013-11-11

    A bottom mounted upward looking Simrad EK60 120-kHz echo sounder was used to study scattering layers (SLs) and individuals of the krill Meganyctiphanes norvegica. The mooring was situated at 150-m depth in the Oslofjord, connected with an onshore cable for power and transmission of digitized data. Records spanned 5 months from late autumn to spring. A current meter and CTD was associated with the acoustic mooring and a shore-based webcam monitored ice conditions in the fjord. The continuous measurements were supplemented with intermittent krill sampling campaigns and their physical and biological environment.The krill carried out diel vertical migration (DVM) throughout the winter, regardless of the distribution of potential prey. The fjord froze over in mid-winter and the daytime distribution of a mid-water SL of krill immediately became shallower associated with snow fall after freezing, likely related to reduction of light intensities. Still, a fraction of the population always descended all the way to the bottom, so that the krill population by day seemed to inhabit waters with light levels spanning up to six orders of magnitude. Deep-living krill ascended in synchrony with the rest of the population in the afternoon, but individuals consistently reappeared in near-bottom waters already? 1 h after the ascent. Thereafter, the krill appeared to undertake asynchronous migrations, with some krill always being present in near-bottom waters even though the entire population appeared to undertake DVM. The Author 2013. Published by Oxford University Press. All rights reserved.

  14. Volcanic Structure of the Gakkel Ridge at 85°E

    Science.gov (United States)

    Willis, C.; Humphris, S.; Soule, S. A.; Reves-Sohn, R.; Shank, T.; Singh, H.

    2007-12-01

    We present an initial volcanologic interpretation of a magmatically-robust segment of the ultra-slow spreading (3- 7 mm/yr) Gakkel Ridge at 85°E in the eastern Arctic Basin based on surveys conducted during the July 2007 Arctic GAkkel Vents Expedition (AGAVE). A previous expedition (2001 AMORE) and seismic stations in the area found evidence for active hydrothermal circulation and seismicity that suggested volcanic activity may be ongoing at 85°E. We examine multi-beam bathymetric data, digital imagery, and rock and sediment samples in order to determine the nature of volcanic accretion that is occurring in this environment including the distribution of flow types and their relationship to features of the axial valley. Raw multi-beam bathymetric data was logged by the Kongsberg EM 120 1°x1° multi-beam echo sounder aboard the icbreaker IB Oden. Digital imagery was recorded on five video and still cameras mounted on the CAMPER fiber-optic wireline vehicle, which was towed 1-3m above the seafloor. Digital imagery was recorded on thirteen CAMPER drift-dives over interesting bathymetry including: a volcanic ridge in the axial valley named Duque's Hill, and Oden and Loke volcanoes that are part of the newly discovered Asgard volcanic chain. Talus, lava flows, and volcaniclastics were sampled with the clamshell grabber and slurp suction sampler on CAMPER. A variety of lava morphologies are identified in the imagery including large basalt pillows with buds and other surface ornamentation, lava tubes, lobates, sheet flows, and a thick cover of volcaniclastic sediment over extensive areas suggestive of explosive volcanic activity.

  15. Combining airborne and satellite remote sensing programs to repress illegal oil discharges in restricted sea areas

    International Nuclear Information System (INIS)

    Price, M.

    2005-01-01

    An airborne surveillance program has been conducted over the Belgian part of the North Sea since 1991. The role of the program is to detect infringements on the Marpol Convention via remote sensing, and to take legal action against polluters through the use of recorded observations. Although Belgium has a restricted sea area of about 3,500 km with no fixed offshore oil installations, a pollution risk is constantly present due to 2 dense traffic separation schemes close to the shoreline. The Belgian marine areas and adjacent waters are regularly scanned with a Side Looking Airborne Radar (SLAR) on board a remote sensing aircraft. This paper describes an evaluation trial that the Belgian Management Unit of the North Sea Mathematical Models (MUMM) joined in 2004, together with various agencies from the United Kingdom, Germany and the Netherlands. The trial consists of a cost-sharing satellite service for oil detection with ENVISAT ASAR data. The trial was co-funded by the European Space Agency (ESA) and run by Kongsberg Satellite Services. MUMM's objective was to evaluate the effectiveness and operational character of satellite services for detecting oil spills at sea. The results of the 3 month trial have indicated that aerial remote sensing for the detection of illegal oil discharges at sea increases the chances of catching polluters more efficiently, with improved chances of evidence collecting. It was concluded that when various services are integrated and strict operational conditions are met, satellite services may prove to be valuable in restricted, very densely navigated national waters that are easily reached by airborne means. 12 refs., 8 tabs., 3 figs

  16. Seep Detection using E/V Nautilus Integrated Seafloor Mapping and Remotely Operated Vehicles on the United States West Coast

    Science.gov (United States)

    Gee, L. J.; Raineault, N.; Kane, R.; Saunders, M.; Heffron, E.; Embley, R. W.; Merle, S. G.

    2017-12-01

    Exploration Vessel (E/V) Nautilus has been mapping the seafloor off the west coast of the United States, from Washington to California, for the past three years with a Kongsberg EM302 multibeam sonar. This system simultaneously collects bathymetry, seafloor and water column backscatter data, allowing an integrated approach to mapping to more completely characterize a region, and has identified over 1,000 seafloor seeps. Hydrographic multibeam sonars like the EM302 were designed for mapping the bathymetry. It is only in the last decade that major mapping projects included an integrated approach that utilizes the seabed and water column backscatter information in addition to the bathymetry. Nautilus mapping in the Eastern Pacific over the past three years has included a number of seep-specific expeditions, and utilized and adapted the preliminary mapping guidelines that have emerged from research. The likelihood of seep detection is affected by many factors: the environment: seabed geomorphology, surficial sediment, seep location/depth, regional oceanography and biology, the nature of the seeps themselves: size variation, varying flux, depth, and transience, the detection system: design of hydrographic multibeam sonars limits use for water column detection, the platform: variations in the vessel and operations such as noise, speed, and swath overlap. Nautilus integrated seafloor mapping provided multiple indicators of seep locations, but it remains difficult to assess the probability of seep detection. Even when seeps were detected, they have not always been located during ROV dives. However, the presence of associated features (methane hydrate and bacterial mats) serve as evidence of potential seep activity and reinforce the transient nature of the seeps. Not detecting a seep in the water column data does not necessarily indicate that there is not a seep at a given location, but with multiple passes over an area and by the use of other contextual data, an area may

  17. Seafloor mapping of the southeast Iberian margin (from Cabo de Palos to Cabo de Gata)

    Science.gov (United States)

    Lastras, Galderic; Leon, César; Elvira, Elena; Pascual, Laura; Muñoz, Araceli; de Cárdenas, Enrique; Acosta, Juan; Canals, Miquel

    2014-05-01

    We present the multibeam bathymetry and derived maps of the southeast Iberian margin from Cabo de Palos to Cabo de Gata, 37º35'N to 35º45'N and 2º10'W to 0º20'E, from the coastline down to the Algero-Balearic abyssal plain at depths exceeding 2600 m. The edition of of the maps is carried out within the Complementary Action VALORPLAT ("Scientific valorisation of multibeam bathymetry data from the Spanish continental shelf and slope"), funded by the Spanish Ministry of Economy and Competitivity. The multibeam bathymetry data of the slope and abyssal plain were obtained during different surveys in 2004, 2006 and 2007 on board R/V Vizconde de Eza with a Simrad EM300 multibeam echo-sounder as part of the CAPESME Project, a collaboration between the Spanish Institute of Oceanography (IEO) and General Secretariat of Fisheries (SGP), primarily aiming at creating maps of the fishing grounds of the Mediterranean continental margins of Spain. Multibeam bathymetry data from the continental shelf were obtained within the ESPACE project, also in a cooperative frame between IEO and SGP. The map series is constituted by a general map at 1:400,000 scale and 14 detailed maps at 1:75,000 scale, which include inset maps on slope gradients and seafloor nature (rock or sediment type), the later obtained with rock dredges and Shipeck sediment dredges. Both the detailed maps and the general map are available in paper print, and the whole collection is also distributed in an edited USB. The geological features displayed in the different maps include the continental shelf, with abundant geomorphic features indicative of past sea-level changes, the continental slope carved by the Palos, Tiñoso, Cartagena Este, Cartagena Oeste, Águilas, Almanzora, Alias, Garrucha and Gata submarine canyons, the Mazarrón, Palomares and Al-Mansour escarpments, the Abubácer, Maimonides and Yusuf ridges, the Águilas and Al-Mansour seamounts, and the Algero-Balearic abyssal plain where prominent

  18. Influences of spatial and temporal variability of sound scattering layers on deep diving odontocete behavior

    Science.gov (United States)

    Copeland, Adrienne Marie

    Patchiness of prey can influence the behavior of a predator, as predicted by the optimal foraging theory which states that an animal will maximize the energy gain while minimizing energy loss. While this relationship has been studied and is relatively well understood in some terrestrial systems, the same is far from true in marine systems. It is as important to investigate this in the marine realm in order to better understand predator distribution and behavior. Micronekton, organisms from 2-20 cm, might be a key component in understanding this as it is potentially an essential link in the food web between primary producers and higher trophic levels, including cephalopods which are primary prey items of deep diving odontocetes (toothed whales). My dissertation assesses the spatial and temporal variability of micronekton in the Northwestern Hawaiian Islands (NWHI), the Main Hawaiian Islands' (MHI) Island of Hawaii, and the Gulf of Mexico (GOM). Additionally it focuses on understanding the relationship between the spatial distribution of micronekton and environmental and geographic factors, and how the spatial and temporal variability of this micronekton relates to deep diving odontocete foraging. I used both an active Simrad EK60 echosounder system to collect water column micronekton backscatter and a passive acoustic system to detect the presence of echolocation clicks from deep diving beaked, sperm, and short-finned pilot whales. My results provide insight into what might be contributing to hotspots of micronekton which formed discrete layers in all locations, a shallow scattering layer (SSL) from the surface to about 200 m and a deep scattering layer (DSL) starting at about 350 m. In both the GOM and the NWHI, the bathymetry and proximity to shore influenced the amount of micronekton backscatter with locations closer to shore and at shallower depths having higher backscatter. We found in all three locations that some species of deep diving odontocetes were

  19. Latitudinal changes of euphausiid assemblages related to the morphological variability of the sound scattering layer along Baja California, October 1994

    Directory of Open Access Journals (Sweden)

    J. Gómez-Gutiérrez

    1999-03-01

    Full Text Available Latitudinal changes in the euphausiid assemblages were compared to the morphological structure (size and compactness of the sound scattering layer (SSL during ten 24-h surveys made in October 1994 along the west coast of Baja California, México. During October, upwelling was found in the northern area from Punta Eugenia (28°N to Ensenada (30°N dominated by temperate species from the California Current System. In the southern sector of the peninsula, a northward movement of tropical waters transports a tropical zooplankton assemblage near Bahia Magdalena (24°N. The aggregation and the dispersion of the whole SSL (plankton and nekton were investigated using a single beam vertical echosounder, Simrad EY-200, working at 200 kHz and the Hydro Acoustic Data Acquisition System (HADAS that estimates patch variables of density and compactness. The size and shape of the SSL were obtained from the echogram visualization. The euphausiid species composition was obtained using an Isaacs-Kidd midwater trawl, bongo nets, and opening-closing nets. At Ensenada and Punta Eugenia, an area inhabited by a temperate euphausiid assemblage, large and dense SSLs were recorded over the continental shelf (mean sizes were 10-km and 7-km long with mean compactness of 15% and 19%. These regions were dominated by the neritic species Nyctiphanes simplex and the temperate species Nematoscelis difficilis, Euphausia pacifica, and Thysanoessa spinifera. In the southern area, a tropical euphausiid assemblage, dominated by Euphausia eximia, E tenera, and E. distinguenda, inhabits smaller and dispersed SSLs (mean size 5-km long and 11% compactness located in the offshore area. The euphausiid biomass of the most abundant species indicated, N. simplex and N. difficilis, had their highest standing stock in the north (393 and 643 mg C 1000 m-3, with E. eximia in the southern area (186 mg C 1000 m-3. Euphausiid assemblage development in different biological environments, is evidenced

  20. High resolution bathymetric and sonar images of a ridge southeast of Terceira Island (Azores plateau)

    Science.gov (United States)

    Lourenço, N.; Miranda, J. M.; Luis, J.; Silva, I.; Goslin, J.; Ligi, M.

    2003-04-01

    The Terceira rift is a oblique ultra-slow spreading system where a transtensive regime results from differential movement between Eurasian and African plates. So far no classical ridge segmentation pattern has here been observed. The predominant morphological features are fault controlled rhombic shaped basins and volcanism related morphologies like circular seamounts and volcanic ridges. We present SIMRAD EM300 (bathymetry + backscatter) images acquired over one of these ridges located SE of Terceira Island, during the SIRENA cruise (PI J. Goslin), which complements previous TOBI mosaics performed over the same area during the AZZORRE99 cruise (PI M. Ligi). The ridge presents a NW-SE orientation, it is seismically active (a seismic crisis was documented in 1997) and corresponds to the southern branch of a V shape bathymetric feature enclosing the Terceira Island and which tip is located west of the Island near the 1998 Serreta ridge eruption site. NE of the ridge, the core of the V, corresponds to the North Hirondelle basin. All this area corresponds mainly to Brunhes magnetic epoch. The new bathymetry maps reveal a partition between tectonic processes, centred in the ridge, and volcanism present at the bottom of the North Hirondelle basin. The ridge high backscatter surface is cut by a set of sub-parallel anastomosed normal faults striking between N130º and N150º. Some faults present horse-tail terminations. Fault splays sometimes link to neighbour faults defining extensional duplexes and fault wedge basins and highs of rhombic shape. The faulting geometry suggests that a left-lateral strike slip component should be present. The top of the ridge consists on an arched demi-.horst, and it is probably a volcanic structure remnant (caldera system?), existing prior to onset of the tectonic stage in the ridge. Both ridge flanks display gullies and mass wasting fans at the base of the slope. The ridge vicinities are almost exclusively composed of a grayish homogeneous

  1. Seabed sediment classification for monitoring underwater nourishments using time series of multi-beam echo-soundings

    Science.gov (United States)

    Gaida, T. C.; Snellen, M.; van Dijk, T. A. G. P.; Simons, D. G.

    2017-12-01

    Coastal erosion induced by natural processes, such as wind, waves, tidal currents, or human interferences endangers human beings, infrastructure, fauna and flora at the oceans and rivers all over the world. In The Netherlands, in particular the North Sea islands are strongly affected by sediment erosion. To protect and stabilize the coastline, beach and shoreface nourishments are frequently performed. Thereby, sediment reservoirs are created that replace the eroded sediments. Increasing the long-term efficiency of coastal protection requires monitoring of the temporal and spatial development of the coastal nourishments. Multi-beam echo-sounders (MBES) allow for detailed and comprehensive investigations of the seabed composition and structure. To investigate the potential of using MBES for monitoring nourishments in a tidal inlet, four MBES surveys per year are carried out at the Dutch Wadden island Ameland. A pre-nourishment MBES survey was performed in April 2017 and the subsequent post-nourishment survey will take place in September 2017. Both surveys are equipped with a Kongsberg EM 2040C dual-head MBES and are supported with extensive grab sampling. In this study the use of MBES backscatter and bathymetry data are considered as an approach for monitoring coastal nourishments. The aim is to develop a monitoring procedure that allows for comparing MBES data taken during different surveys, i.e., with variations in environmental conditions, MBES characteristics and acquisition procedures. Different unsupervised and supervised acoustic seafloor classification techniques are applied to the processed MBES data to classify the seabed sediments. The analysis of the pre-nourishment MBES data indicates that the backscatter and consequently the classification are highly driven by the abundancy of shell fragments. These results will be used as a baseline to investigate the accumulation of the underwater nourishments. Independent grab samples will be used to select the

  2. Hydroacoustic detection of dumped ammunition in the Ocean with multibeam snippet backscatter analyses. A case study from the 'Kolberger Heide' ammunition dump site (Baltic Sea, Germany)

    Science.gov (United States)

    Kunde, Tina; Schneider von Deimling, Jens

    2016-04-01

    Dumped ammunition in the sea is a matter of great concern in terms of safe navigation and environmental threads. Because corrosion of the dumped ammunition's hull is ongoing, future contamination of the ambient water by their toxic interior is likely to occur. The location of such dump sites is approximately known from historical research and ship log book analyses. Subsequent remote sensing of ammunition dumping sites (e.g. mines) on the seafloor is preferentially performed with hydro-acoustic methods such as high resolution towed side scan or by the sophisticated synthetic aperture sonar approach with autonomous underwater vehicles. However, these are time consuming and expensive procedures, while determining the precise position of individual mines remains a challenging task. To mitigate these shortcomings we suggest using ship-born high-frequency multibeam sonar in shallow water to address the task of mine detection and precise localization on the seabed. Multibeam sonar systems have improved their potential in regard to backscatter analyses significantly over the past years and nowadays present fast and accurate tools for shallow water surveying to (1) detect mines in multibeam snippet backscatter data (2) determine their precise location with high accuracy intertial navigation systems. A case study was performed at the prominent ammunition dumping site 'Kolberger Heide' (Baltic Sea, Germany) in the year 2014 using a modern hydro-acoustic multibeam echosounder system with 200-400 kHz (KONGSBERG EM2040c). With an average water depth of not even 20 m and the proximity to the shore line and dense waterways, this investigated area requires permanent navigational care. Previously, the study area was surveyed by the Navy with the very sophisticated HUGIN AUV equipped with a synthetic aperture sonar with best resolution by current technology. Following an evaluation of the collected data, various ammunition bodies on the sea floor could be clearly detected. Analyses

  3. E/V Nautilus Detection of Isolated Features in the Eastern Pacific Ocean: Newly Discovered Calderas and Methane Seeps

    Science.gov (United States)

    Raineault, N.; Irish, O.; Lubetkin, M.

    2016-02-01

    The E/V Nautilus mapped over 80,000 km2 of the seafloor in the Gulf of Mexico and Eastern Pacific Ocean during its 2015 expedition. The Nautilus used its Kongsberg EM302 multibeam system to map the seafloor prior to remotely operated vehicle (ROV) dives, both for scientific purposes (site selection) and navigational safety. The Nautilus also routinely maps during transits to identify previously un-mapped or unresolved seafloor features. During its transit from the Galapagos Islands to the California Borderland, the Nautilus mapped 44,695 km2 of seafloor. Isolated features on the seafloor and in the water-column, such as calderas and methane seeps, were detected during this data collection effort. Operating at a frequency of 30 kHz in waters ranging from 1000-5500 m, we discovered caldera features off the coast of Central America. Since seamounts are known hotspots of biodiversity, locating new ones may enrich our understanding of seamounts as "stepping stones" for species distribution and ocean current pathways. Satellite altimetry datasets prior to this data either did not discern these calderas or recognized the presence of a bathymetric high without great detail. This new multibeam bathymetry data, gridded at 50 m, gives a precise look at these seamounts that range in elevation from 350 to 1400 m from abyssal depth. The largest of the calderas is circular in shape and is 10,000 m in length and 5,000 m in width, with a distinct circular depression at the center of its highest point, 1,400 m above the surrounding abyssal depth. In the California Borderland region, located between San Diego and Los Angeles, four new seeps were discovered in water depths from 400-1,020 m. ROV exploration of these seeps revealed vent communities. Altogether, these discoveries reinforce how little we know about the global ocean, indicate the presence of isolated deep-sea ecosystems that support biologically diverse communities, and will impact our understanding of seafloor habitat.

  4. NOAA Office of Ocean Exploration: EM302 Multibeam Survey of the Sangihe-Talaud Region, North Sulawesi, Indonesia

    Science.gov (United States)

    Lobecker, M.; Malik, M.; Johnson, J. E.; Boettcher, M. S.

    2010-12-01

    The NOAA Ship Okeanos Explorer has just completed a successful 2010 field season, including its first partnership-building mission to Indonesia, INDEX-SATAL 2010 (Indonesia Exploration Sangihe-Talaud region). The mission was part of President Obama’s initiative to build science and technology partnerships with Muslim nations. The Okeanos Explorer is equipped with progressive technology, including a Kongsberg EM302 (30 kHz) multibeam system with bottom backscatter and water column backscatter data collection capabilities. The mapping in the Sangihe-Talaud region of the Celebes Sea produced over 31,000 square kilometers of high resolution data, ranging in depth from 244 meters to more than 7000 meters. The mapped regions include the majority of the western side of the central Sangihe volcanic arc and a narrow transect across the arc in the south. A ~350 km long transect across the northern end of the central Sangihe arc was also mapped, north of the Talaud Islands, and extends eastward across the Sangihe Basin and Molucca Trench to the Philippine Trench. A recent synthesis of deep marine data by Pubellier et al. (2005)1 documents numerous active and inactive subduction zones of opposite polarity in this narrow region. The high resolution bathymetry reveals new details of the seafloor morphology in this complex tectonic regime. At least five seamounts were mapped, including an unknown 1500 meter high seamount and the volcano Kawio Barat, which rises approximately 3500 meters from the seafloor and is the site of white smokers and surprisingly dense and diverse deepwater biological communities. Several additional features were observed, including submarine channels, fans, debris aprons with blocks up to 800 meters in diameter, accretionary ridges and basins, trenches, and some flat topped seamounts. These well-defined features are consistent with the complex interactions between arc development, mass wasting, and subduction. These data provide new opportunities for

  5. Survey of referrals and medical reports in optometric practices in Norway: midterm findings from a 3-year prospective Internet-based study

    Directory of Open Access Journals (Sweden)

    Lundmark PO

    2017-05-01

    Full Text Available Per O Lundmark,1 Knut Luraas1,2 1Department of Optometry, Radiography and Lighting Design, Faculty of Health and Social Sciences, University College of Southeast Norway, Kongsberg, 2Rjukan Synssenter Optometri, Rjukan, Norway Purpose: The increasing demand for primary eye care due to an aging population implicates an enhanced role of optometrists in the communities. The primary objective of this study was to investigate the rate of referrals and returning medical reports between optometrists and health care professionals in Norway. The secondary objectives were to investigate the conformity of diagnoses in referrals and medical reports, the extent of optometric follow-up examinations and the use of ophthalmic diagnostic drugs in optometric practice.Materials and methods: This study is an ongoing prospective electronic survey administered on the Internet between November 2014 and December 2017. Optometrists in private optometric practice are eligible. Participants register data for up to 1 year, including examinations and the use of ophthalmic diagnostic drugs; referrals, including International Classification of Primary Care, second edition (ICPC-2 codes; medical reports, including the ICD-10 codes; and optometric follow-up enquiries. Analysis of agreement between referred and diagnosed conditions was made possible by encoding patients’ ID.Results: Seventeen months into the study, 67 optometrists were included (Female: 60%, mean age: 41 years.. There were 49,510 registered examinations (60% general, 28% contact lens, 12% auxiliary. Diagnostic drugs were used in 4% of these and in 14% of the examinations that resulted in a referral. There were 1,779 referrals (97% to ophthalmologists. Top three diagnoses were cataract (36%, glaucoma (11%, and age-related macular degeneration (7%. There were 1,036 returned medical reports, of which 76% could be linked with registered referrals. Diagnostic agreement was observed in 80% of the cases (74% for

  6. Sensory impairments in community health care: a descriptive study of hearing and vision among elderly Norwegians living at home

    Directory of Open Access Journals (Sweden)

    Haanes GG

    2014-05-01

    Full Text Available Gro Gade Haanes,1 Marit Kirkevold,2 Gunnar Horgen,1 Dag Hofoss,2 Grethe Eilertsen1 1Buskerud and Vestfold University College, Kongsberg, Norway; 2University of Oslo, Oslo, Norway Background: Hearing and vision impairments increase with age and are common risk factors for functional decline reduced social participation and withdrawal. Objective: Describe the hearing and vision of home care patients older than 80 years. Methods: Ninety-three older adults (80+ years receiving home care were screened for hearing and vision in their homes. Data were collected using a HEINE Mini 3000® Otoscope to examine the eardrum and presence of earwax, an Entomed SA201-IV portable pure-tone audiometer to measure the pure-tone average (PTAV, a logarithm of the minimum angle of resolution chart to measure visual acuity (VA, and the Combined Serious Sensory Impairment interview guide. Results: Slight and moderate hearing impairments were found in 41% and 47% of the population, respectively (mean PTAV =40.4 dB for the better ear, and 40% and 56% had impaired and slightly impaired vision, respectively (mean VA =0.45 for the better eye. The participants' self-assessments of hearing and vision were only weakly correlated with PTAV and VA values. The visual function was significantly worse in men than in women (P=0.033. Difficulty in performing instrumental activities of daily living because of hearing and vision impairments was experienced by 17% of the participants, whereas 76% experienced no difficulties. When many people were present, 72% of the participants found it difficult to understand speech. Nearly 30% found it tiring to read, and 41% could not read very small print. Conclusion: The patients’ self-assessments of their hearing and vision did not correlate strongly with their VA and PTAV scores. Asking the elderly about their overall hearing and vision ability is not sufficient for detecting sensory impairment, and asking more specific questions about what

  7. Stuck between a rock and a hard place: the work situation for nurses as leaders in municipal health care

    Directory of Open Access Journals (Sweden)

    Nilsen ER

    2016-04-01

    Full Text Available Etty R Nilsen,1 Anja H Olafsen,1 Anne Grethe Steinsvåg,2 Hallgeir Halvari,1 Ellen K Grov31Department of Strategy and Finance, School of Business, University College of Southeast-Norway, 2Department of Nursing Science, Faculty of Health Sciences, University College of Southeast-Norway, Kongsberg, 3Department of Nursing and Health Promotion, Faculty of Health Sciences, Oslo and Akershus University College, Oslo, NorwayBackground: The paper aims to present how nursing leaders in the municipal health care perceive the interaction with and support from their superiors and peers. The paper further aims to identify the leaders’ vulnerability and strength at work in the current situation of shortage of manpower and other resources in the health care sector. This is seen through the lens of self-determination theory.Methods: Qualitative interviews were conducted with nine nursing leaders in nursing homes and home-care services, which, in part, capture the municipal health care service in a time of reform.Results: The nursing leaders are highly independent regarding their role as leaders. They act with strength and power in their position as superiors for their own staff, but they lack support and feel left alone by their leader, the municipal health director. The relation between the nursing leaders and their superiors is characterized by controlling structures and lack of autonomy support. As a consequence, the nursing leaders’ relations with subordinates and particularly peers, contribute to satisfy their needs for competence and relatedness, and, to some extent, autonomy. However, this cannot substitute for the lack of support from the superior level.Conclusion: The paper maintains a need to increase the consciousness of the value of horizontal support and interaction with peers and subordinates for the municipal nursing leader. Also, the need for increased focus on “the missing link” upward between the municipal health director and the

  8. Comparative analysis of hydroacoustic lakebed classification in three different Brazilian reservoirs

    Science.gov (United States)

    Hilgert, Stephan; Sotiri, Klajdi; Fuchs, Stephan

    2017-04-01

    Until today, the surface of artificial water bodies around the world reached an area of around 500,000 km2 equaling one third of the surface of natural water bodies. Most of the constructed waster bodies are reservoirs with a variety of usage purposes, reaching from drinking water supply, electricity production, flood protection to recreation. All reservoirs have in common, that they disrupt riverine systems and their biochemical cycles and promote the accumulation of sediments upstream of the dam. The accumulated sediments contain organic matter, nutrients and/or pollutants which have a direct influence on the water quality within the impoundment. Consequently, detailed knowledge about the amount and the quality of accumulated sediments is an essential information for reservoir management. In many cases the extensive areas covered by the impoundments make it difficult and expensive to assess sediment characteristics with a high spatial resolution. Spatial extrapolations and mass balances based on point information may suffer from strong deviations. We combined sediment point measurements (core and grab sampling) with hydroacoustic sediment classification in order to precisely map sediment parameters. Three different reservoirs (Vossoroca, Capivari, Passauna) in the south-east of Brazil were investigated between 2011 and 2015. A single beam echosounder (EA 400, Kongsberg) with two frequencies (200 & 38 kHz) was used for the hydroacoustic classification. Over 50 core samples and 30 grab samples were taken for physical and chemical analysis to serve as ground truthing of the hydroacoustic measurements. All three reservoirs were covered with dense measurement transects allowing for a lakebed classification of the entire sediment surface. Significant correlations of physical parameters like grain size distribution and density as well chemical parameters like organic carbon content and total phosphorous with a selection of hydroacoustic parameters were obtained. They

  9. Assessment of COTS IR image simulation tools for ATR development

    Science.gov (United States)

    Seidel, Heiko; Stahl, Christoph; Bjerkeli, Frode; Skaaren-Fystro, Paal

    2005-05-01

    Following the tendency of increased use of imaging sensors in military aircraft, future fighter pilots will need onboard artificial intelligence e.g. ATR for aiding them in image interpretation and target designation. The European Aeronautic Defence and Space Company (EADS) in Germany has developed an advanced method for automatic target recognition (ATR) which is based on adaptive neural networks. This ATR method can assist the crew of military aircraft like the Eurofighter in sensor image monitoring and thereby reduce the workload in the cockpit and increase the mission efficiency. The EADS ATR approach can be adapted for imagery of visual, infrared and SAR sensors because of the training-based classifiers of the ATR method. For the optimal adaptation of these classifiers they have to be trained with appropriate and sufficient image data. The training images must show the target objects from different aspect angles, ranges, environmental conditions, etc. Incomplete training sets lead to a degradation of classifier performance. Additionally, ground truth information i.e. scenario conditions like class type and position of targets is necessary for the optimal adaptation of the ATR method. In Summer 2003, EADS started a cooperation with Kongsberg Defence & Aerospace (KDA) from Norway. The EADS/KDA approach is to provide additional image data sets for training-based ATR through IR image simulation. The joint study aims to investigate the benefits of enhancing incomplete training sets for classifier adaptation by simulated synthetic imagery. EADS/KDA identified the requirements of a commercial-off-the-shelf IR simulation tool capable of delivering appropriate synthetic imagery for ATR development. A market study of available IR simulation tools and suppliers was performed. After that the most promising tool was benchmarked according to several criteria e.g. thermal emission model, sensor model, targets model, non-radiometric image features etc., resulting in a

  10. Internationalisation; KonKraft-rapport 4; Internasjonalisering

    Energy Technology Data Exchange (ETDEWEB)

    2008-07-01

    disintegrate. The obvious strategy to pursuit is to strengthen Norway's position as a dynamic and leading competence center for oil- and gas activities. Recruitment and development of sufficient competencies is generally a major challenge for the oil- and gas trade. Shortage of human capital leads to increased wage pressure which in the long run may weaken profits and competitiveness. In some of the petroleum clusters the companies try to find solutions to counteract the negative effects of the battle for the best brains. Through the project KonKraft INTSOK has unveiled high ambitions concerning increased internationalisation throughout the Norwegian petroleum cluster, except for Northern Norway. Here there is still an opposition against activities in the region, as well as in the Barents sea. INTSOK's intention with the project has been to describe its multitude. Therefore eight very different environments where selected to make a closer study on the development in different regions. The environments represent a variety of sizes, geography and trades. Some of the clusters are new or under establishment, others are already in full operation. Together the eight environments cover a major part of the value chain in the Norwegian offshore sector. The project has clearly demonstrated that cluster development contributes both to internationalisation as well as keeping the companies in Norway. Some main findings: The positive development in the drilling cluster of Southern Norway - the Node cluster - has created strong impact: The cluster ranks among the world's leading on drilling equipment and barely any oil or gas environment has had a similar expansion. The Kongsberg environment is not an offshore cluster, but an overall technology cluster where offshore applications is one of several technology areas. The companies develop and produce a broad range of advanced products and systems. The turnover among the offshore companies amounts to 65% of the total turnover for

  11. Mapping giant mass transport deposits (MTDs) for delineating the extended Continental Shelf of Spain to the West of Canary Islands according UNCLOS Art. 76

    Science.gov (United States)

    Somoza, Luis; Medialdea, Teresa; León, Ricardo; Vázquez, Juan T.; González, Javier; Palomino, Desiree; González-Aller, Daniel; Fernández-Salas, Luis M.; Espinosa, Salvador

    2017-04-01

    On 19 December 2014, Spain presented a third partial submission for the delineation of the Extended Continental in the area west of the Canary Islands to the Commission on the Limits of the Continental Shelf (CLCS) according to the United Nations Convention on the Law of Sea (UNCLOS). The Canary Islands are located within a NE-SW 1,350 km long ridge of hotspot-inferred volcanic islands and seamounts (composed by more of 100, from Lars to Tropic seamounts). This submission has been documented with an extensive dataset specifically obtained for the project during ten oceanographic cruises between 2010 and 2014 aboard the Spanish research vessels Hespérides, Sarmiento de Gamboa and Miguel Oliver. This new dataset allows to investigate an area of 440,000 km2 with acoustic backscatter images and multibeam echosounder bathymetric (MBES) data (Simrad EM-12, EM-120 and EM-302, and Atlas HYDROSWEEP DS), a dense network of 65,800 km of very-high resolution (VHR) seismic lines (including chirp parametric source TOPAS PS-18 and Atlas PARASOUND P-35) and 4,471 km of multichannel seismic reflection lines (MCS) acquired with an array of air-guns yielding a total volume of 4,600 inch3 (75.38 L) and a 3,500 m long streamer composed of 280 channels. In order to determine the Foot of Slope (FoS), the Base of Slope (BoS) region has been traced following geomorphological arguments based on the morphology of the mass transport deposits (MTDs) extended downslope west of the Canary Islands. Based on backscatter and MBEs mapping, and VHR lines, the BoS has been traced by means of a detailed mapping of the debris flow deposits widespread along the slope. Therefore, the seaward limit of the BoS has been traced following the termination of the debris flow sourced from the Canary Island. Otherwise, the landward limit of the BoS has been defined following the morphological changes in the debris flow forced by the breaking in the slope gradient, which form distributary lobes downslope. Finally

  12. Widespread gas emissions in the Sea of Marmara in relation with the tectonic and sedimentary environments: Results from shipborne multibeam echosounder water column imagery (MARMESONET expedition, 2009)

    Science.gov (United States)

    Dupré, Stéphanie; Scalabrin, Carla; Géli, Louis; Henry, Pierre; Grall, Céline; Tary, Jean-Baptiste; Ćaǧatay, Namık.; Imren, Caner

    2010-05-01

    Acoustic systems in marine geosciences are mainly used to explore the seabed and image sub-bottom sedimentary units. However, side-scan sonars and echosounders can detect gas emissions from the seabed into the water column. Recently, advances in technology and computer processing allow carrying out large-scale 3D surveys of the entire water column with multibeam systems, so far dedicated to seabed imagery. A shipborne multibeam survey of the water column in the Sea of Marmara was performed with the R/V Le Suroit during the MARMESONET expedition (4-25 November 2009), that is part of the ESONET (European Seas Observatory NETwork) demonstration mission MarmaraDM. Data were acquired with a Simrad EM302 multibeam echosounder (27-33 kHz, 288 beams, 1°x2°, 2 or 5 ms pulse length) with automatic swath width control and equidistant sounding pattern over water depths varying from 300 to 1300 m. Volume backscattering coefficients were stored with m depth bins along more than 2000 nm acoustic tracks. Gas bubble echoes were very well detected by the EM302 system within the water depth range of the Sea of Marmara, mostly with the central beams but also with the outer beams for the flares with strong backscatter intensity and large imprint. Geo-referenced gas flare 3D visualization is performed with Movies3D software developed for fish school echo description and biomass assessment (Trenkel et al., 2009). The distribution of water column acoustic echoes in the Sea of Marmara reveals that free gas emissions from the seabed are more widespread than expected from previous studies using ROVs, submersibles as well as acoustic methods (Géli et al., 2008; Zitter et al., 2008). Numerous acoustic gas flares were detected in association with the North Anatolian fault system and some appear to be localized on known active fault traces. However, gas emissions also spread around the edges of the sedimentary basins (e.g. Cinarcik and Tekirdag basins) and on structural highs (e.g. Western

  13. 900-m high gas plumes rising from marine sediments containing structure II hydrates at Vestnesa Ridge, offshore W-Svalbard

    Science.gov (United States)

    Smith, Andrew J.; Mienert, Jürgen; Bünz, Stefan; Greinert, Jens; Rasmussen, Tine L.

    2013-04-01

    We study an arctic sediment drift in ~1200 m water depth at Vestnesa Ridge, offshore western Svalbard. The ridge is spotted with pockmarks that range in size from a few meters to hundreds of meters in diameter and centimeters to tens of meters in height (e.g. Vogt et al., 1994). There is a strong negative-polarity seismic reflection below the ridge that is interpreted to record a negative impedance contrast marking the boundary between gas hydrate and water above and free gas and water below: it is the bottom-simulating reflector (BSR). Seismically transparent zones, interpreted as gas chimneys, extend from pockmarks at the seafloor to depths below the BSR (180-220 meters below the seafloor) (Bünz et al., 2012). Gas flares, gas hydrate, and methane-seep-specific biological communities (pogonphora and begiatoa bacterial mats) have been observed adjacent to pockmarks at the ridge (Bünz et al., 2012). We present new single-beam echosounding data that were acquired during 2010 and 2012 cruises on the R/V Helmer Hanssen at Vestnesa Ridge using a Simrad EK60 system that operates at frequencies of 18 and 38 kHz. During both cruises which lasted 3-5 days, we detected continuous bubble release from 4 separate pockmarks in 2010 and 6 separate pockmarks in 2012. There were no noticeable, short-term (hourly or daily) variations in the bubble release from the pockmarks, indicating that the venting from the pockmarks does not undergo rapid changes. Plumes from the pockmarks rise between 875 to 925m above the seafloor to a final water depth of 325 to 275m, respectively. This depth is in excellent agreement with the top of the hydrate stability zone (275 meters below sea level) for the gas composition of hydrate sampled at the ridge (96.31% C1; 3.36% C2; 0.21% C3; 0.11% IC4; 0.01% NC4). This suggests that hydrate skins are forming around the gas bubbles, inhibiting the dissolution of gas, and allowing the bubbles to rise to such great heights in the water column. Our results

  14. Design and Fabrication of Nereid-UI: A Remotely Operated Underwater Vehicle for Oceanographic Access Under Ice

    Science.gov (United States)

    Whitcomb, L. L.; Bowen, A. D.; Yoerger, D.; German, C. R.; Kinsey, J. C.; Mayer, L. A.; Jakuba, M. V.; Gomez-Ibanez, D.; Taylor, C. L.; Machado, C.; Howland, J. C.; Kaiser, C. L.; Heintz, M.; Pontbriand, C.; Suman, S.; O'hara, L.

    2013-12-01

    -to-end propulsive efficiency of between 0.3 and 0.4 at a transit speed of 1 m/s based on testing conducted at WHOI. CAMERAS: Video imagery is one of the principal products of Nereid-UI. Two fiber-optic telemetry wavelengths deliver 1.5 Gb/s uncompressed HDSDI video to the support vessel in real time, supporting a Kongsberg OE14-522 hyperspherical pan and tilt HD camera and several utility cameras. PROJECT STATUS: The first shallow-water vehicle trials are scheduled for September 2013. The trials are designed to test core vehicle systems particularly the power system, main computer and control system, thrusters, video and telemetry system, and to refine camera, lighting and acoustic sensor placement for piloted and closed-loop control, especially as pertains to working near the underside of ice. Remaining vehicle design tasks include finalizing the single-body deployment concept and depressor, populating the scientific sensing suite, and the software development necessary to implement the planned autonomous return strategy. Final design and fabrication for these remaining components of the vehicle system will proceed through fall 2013, with trials under lake ice in early 2014, and potential polar trials beginning in 2014-15. SUPPORT: NSF OPP (ANT-1126311), WHOI, James Family Foundation, and George Frederick Jewett Foundation East.

  15. The Project for the Extension of the Continental Shelf - the Portuguese experience

    Science.gov (United States)

    Madureira, Pedro; Ribeiro, Luísa P.; Roque, Cristina; Henriques, Guida; Brandão, Filipe; Dias, Frederico; Simões, Maria; Neves, Mariana; Conceição, Patricia; Botelho Leal, Isabel; Emepc, Equipa

    2017-04-01

    Under the United Nations Convention on the Law of the Sea (UNCLOS), the continental shelf is a juridical term used to define a submarine area that extends throughout the natural prolongation of a land territory, where the coastal State exercises sovereign rights for the purpose of exploring it and exploiting its natural resources. Article 76 provides a methodology for determining the outer edge of the continental margin and to delineate the outer limits of the continental shelf. The task of preparing the Portuguese submission to the Commission on the Limits of the Continental Shelf was committed to the Task Group for the Extension of the Continental Shelf (EMEPC), which formally began its activity in January 2005. At that time, the existing national capacity to conduct such a task was very limited in its hydrographic, geological and geophysical components. A great effort has been made by Portugal to overcome these weaknesses and develop a strategy to submit the proposal for the extension of the continental shelf beyond 200 nautical miles on 11th May of 2009. The execution of the project involved the implementation of several complementary strategies including: 1) intensive bathymetric, geophysical and, locally, geological data acquisition; 2) acquisition/development of new stand-alone and ship mounted equipment; 3) interactions with universities and research institutes, with emphasis in R&D initiatives; 4) creation of critical mass in deep-sea research by promoting advanced studies on: International Law, Geophysics, Geology, Hydrography, Biology, amongst others; 5) promotion of the sea as a major national goal, coupled with an outreach strategy. Until now, more than 1050 days of surveying have resulted in a large scale seafloor mapping using two EM120 and one EM710 multibeam echosounders from Kongsberg mounted on two hydrographic vessels. The surveys follow IHO Order 2 Standard (SP44, 5th Edition) and cover an area over 2.6 million km2. A multichannel reflection

  16. Implementation of the new hydrographic technologies for bottom topography and seafloor gas venting investigations in the russian northern seas

    Science.gov (United States)

    Koloskov, Evgenii

    2017-04-01

    -hydrates survey is stated. The attention is paid to the implementation of the parametric sub bottom profilers - the low frequency sonar for the sea bottom vertical section investigation. The ability for the integrated presentation of the multibeam bathymetry and vertical curtains in the 3D environment are discussed. As an example of the modern swath survey results achieved with Kongsberg EM2040CD MB and hydrographic information technology QINSy/ Fledermause, are discussed and presented. This survey was performed for the RosNeft company in the Kara sea. Recommendations for the implementation of the multi beam echo sounder and parametric sub bottom profiler for the combined hydrographic and submarine gas-hydrates survey in the Russian northern seas are delivered.The gas-hydrate survey guidelines using MB and QINSy/Fledermause software are provided. The hydrographic software tools used to process and analyze the bathymetry can create the seafloor DTM with the high degree of resolution and provide 3D visualization.These new possibilities provide such realistic view of the sea bottom relief and environment that can be characterized as the marine landscapes. Thus it became possible to investigate the relief morphological peculiarities and obtain the information about the relief genesis. This opens the new opportunities for using the acoustic techniques for varies types of marine activity including the bottom environmental study. The appearance of the bottom thermokarst activity derived from the high resolution DTM generated from the real time MB data is presented. The bottom thermokarst provides the potential threat for underwater pipelines and other submarine communications. The arctic bottom relief peculiarities are also covered including grounded hummock traces and dome-shaped elevations. The investigation of such bottom land forms has become possible recently as the result of implementing the wide swath survey methods. Such unique relief features are in general related to seabed