WorldWideScience

Sample records for hull-mounted kongsberg simrad

  1. Velocity Data collected from moored Hull-Mounted Acoustic Doppler Current Profilers positioned in Vieques Sound and Virgin Passage in the US Caribbean

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Velocity data were collected from Hull-Mounted Acoustic Doppler Current Profilers moored across Virgin Passage between Culebra, Puerto Rico and St. Thomas, USVI, and...

  2. Historical mineral collections in the silver mining town of Kongsberg, Norway

    NARCIS (Netherlands)

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

    2004-01-01

    The discovery of native silver deposits at Kongsberg, Norway, in 1623 created interest for silver specimens and mineral collecting, also among mining officers. Large collections were donated by J. Hiort, M.T. Brünnich and J. Esmark to the Mining Academy at Kongsberg. The Academy’s collections were i

  3. Historical mineral collections in the silver mining town of Kongsberg, Norway

    NARCIS (Netherlands)

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

    2004-01-01

    The discovery of native silver deposits at Kongsberg, Norway, in 1623 created interest for silver specimens and mineral collecting, also among mining officers. Large collections were donated by J. Hiort, M.T. Brünnich and J. Esmark to the Mining Academy at Kongsberg. The Academy’s collections were i

  4. Historical mineral collections in the silver mining town of Kongsberg, Norway

    NARCIS (Netherlands)

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

    2004-01-01

    The discovery of native silver deposits at Kongsberg, Norway, in 1623 created interest for silver specimens and mineral collecting, also among mining officers. Large collections were donated by J. Hiort, M.T. Brünnich and J. Esmark to the Mining Academy at Kongsberg. The Academy’s collections were

  5. 水面舰艇编队使用舰壳声纳对潜搜索效能分析%Efficiency Analysis of the Surface-ship Formation Searching the Submarine with the Hull-mounted Sonars

    Institute of Scientific and Technical Information of China (English)

    张永生; 翁志刚; 肖雪

    2011-01-01

    This paper builds the model for the surface-ship formation using the hull-mounted sonars to search the submarine,and analyzes the affections caused by the interval distance between the ships and the speed ratio of the submarine and the ship formation.In t%文章建立了水面舰艇编队使用舰壳声纳对潜搜索模型,分析了舰艇间距及敌我舰艇航速大小等因素对搜索效能的影响,提出编队使用舰壳声纳对潜搜索基本方法。

  6. 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 preserv

  7. 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 preserv

  8. 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

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

    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...

  10. 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

    2017-07-01

    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.

  11. 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.

  12. 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...

  13. A field guide for Agency staff operating the SIMRAD EY500 portable scientific echosounder. 2nd draft 3rd August 1999

    OpenAIRE

    Hillary, J.; Lyons, J.; Frear, P.

    1999-01-01

    This manual has been produced by members of the national acoustics group (NAG) and represents the first in a series of outputs designed to promote co-ordination and consistency in Agency hydroacoustic surveys. It is designed as a field guide for Agency staff operating the SIMRAD EY500 portable scientific echosounder. It should be simplistic enough for the newcomer to EY500 to be able to set up and run a mobile hydroacoustic survey with some knowledge of the supporting theory. It should act...

  14. Registration of images from a hull mounted, low frequency synthetic aperture sonar

    NARCIS (Netherlands)

    Bonnett, B.; Hayes, M.; Hunter, A.

    2013-01-01

    Coherent change detection between multiple synthetic aperture sonar (SAS) images is reliant on the images being co-registered with sub-pixel accuracy. In this paper we suggest a technique using available navigation data to reconstruct the images onto a common grid. Data obtained using the MUD SAS sy

  15. Automated detection of submerged navigational obstructions in freshwater impoundments with hull mounted sidescan sonar

    Science.gov (United States)

    Morris, Phillip A.

    The prevalence of low-cost side scanning sonar systems mounted on small recreational vessels has created improved opportunities to identify and map submerged navigational hazards in freshwater impoundments. However, these economical sensors also present unique challenges for automated techniques. This research explores related literature in automated sonar imagery processing and mapping technology, proposes and implements a framework derived from these sources, and evaluates the approach with video collected from a recreational grade sonar system. Image analysis techniques including optical character recognition and an unsupervised computer automated detection (CAD) algorithm are employed to extract the transducer GPS coordinates and slant range distance of objects protruding from the lake bottom. The retrieved information is formatted for inclusion into a spatial mapping model. Specific attributes of the sonar sensors are modeled such that probability profiles may be projected onto a three dimensional gridded map. These profiles are computed from multiple points of view as sonar traces crisscross or come near each other. As lake levels fluctuate over time so do the elevation points of view. With each sonar record, the probability of a hazard existing at certain elevations at the respective grid points is updated with Bayesian mechanics. As reinforcing data is collected, the confidence of the map improves. Given a lake's current elevation and a vessel draft, a final generated map can identify areas of the lake that have a high probability of containing hazards that threaten navigation. The approach is implemented in C/C++ utilizing OpenCV, Tesseract OCR, and QGIS open source software and evaluated in a designated test area at Lake Lavon, Collin County, Texas.

  16. New constraints on the structure of Hess Deep from regional- and micro-bathymetry data acquired during RRS James Cook in Jan-Feb 2008 (JC021)

    Science.gov (United States)

    Shillington, D. J.; Ferrini, V. L.; MacLeod, C. J.; Teagle, D. A.; Gillis, K. M.; Cazenave, P. W.; Hurst, S. D.; Scientific Party, J.

    2008-12-01

    In January-February 2008, new geophysical and geological data were acquired in Hess Deep using the RRS James Cook and the British ROV Isis. Hess Deep provides a tectonic window into oceanic crust emplaced by fast seafloor spreading at the East Pacific Rise, thereby offering the opportunity to test competing hypotheses for oceanic crustal accretion. The goal of this cruise was to collect datasets that can constrain the structure and composition of the lower crustal section exposed in the south-facing slope of the Intrarift Ridge just north of the Deep, and thus provide insights into the emplacement of gabbroic lower crust at fast spreading rates. Additionally, the acquired datasets provide site survey data for IODP Proposal 551-Full. The following datasets were acquired during JC021: 1) regional multibeam bathymetry survey complemented with sub-bottom profiler (SBP) data (in selected areas), 2) two micro-bathymetry surveys, and 3) seafloor rock samples acquired with an ROV. Here we present grids of regional multibeam and microbathymetry data following post-cruise processing. Regional multibeam bathymetry were acquired using the hull-mounted Kongsberg Simrad EM120 system (12 kHz). These data provide new coverage of the northern flank of the rift as far east as 100°W, which show that it comprises of a series of 50- to 100-km-long en echelon segments. Both E-W and NE-SW striking features are observed in the immediate vicinity of the Deep, including in a newly covered region to the SW of the rift tip. Such features might arise due to the rotation of the Galapagos microplate(s), as proposed by other authors. The ROV Isis acquired micro-bathymetry data in two areas using a Simrad SM2000 (200 kHz) multibeam sonar. Data were acquired at a nominal altitude of ~100 m and speed of 0.3 kts to facilitate high-resolution mapping of seabed features and also permit coverage of two relatively large areas. Swath widths were ~200- 350 m depending on noise and seabed characteristics

  17. Detection Capability of the Kongsberg HGLP-System

    Science.gov (United States)

    1975-05-31

    spectra of Southern Sinkiang event 24 January 73, 03:20:20.2. mb - 5.1, depth = 33 km, azimuth ■ 79.3°, distance = 47.3°. ZHI component top, NHI...applied. Th? spectral composition of surface waves from events in Central Asia, i.e. the earthquakes in Sinkiang and Tadzhik, and the explosions in

  18. 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,...

  19. Multibeam observations of mine burial near Clearwater, FL, including comparisons to predictions of wave-induced burial

    Science.gov (United States)

    Wolfson, M.L.; Naar, D.F.; Howd, P.A.; Locker, S.D.; Donahue, B.T.; Friedrichs, Carl T.; Trembanis, A.C.; Richardson, M.D.; Wever, T.F.

    2007-01-01

    A Kongsberg Simrad EM 3000 multibeam sonar (Kongsberg Simrad, Kongsberg, Norway) was used to conduct a set of six repeat high-resolution bathymetric surveys west of Indian Rocks Beach (IRB), just to the south of Clearwater, FL, between January and March 2003, to observe in situ scour and burial of instrumented inert mines and mine-like cylinders. Three closely located study sites were chosen: two fine-sand sites, a shallow one located in ??? 13 m of water depth and a deep site located in ???14 m of water depth; and a coarse-sand site in ???13 m. Results from these surveys indicate that mines deployed in fine sand are nearly buried within two months of deployment (i.e., they sunk 74.5% or more below the ambient seafloor depth). Mines deployed in coarse sand showed a lesser amount of scour, burying until they present roughly the same hydrodynamic roughness as the surrounding rippled bedforms. These data were also used to test the validity of the Virginia Institute of Marine Science (VIMS, Gloucester Point, VA) 2-D burial model. The model worked well in areas of fine sand, sufficiently predicting burial over the course of the experiment. In the area of coarse sand, the model greatly overpredicted the amount of burial. This is believed to be due to the presence of rippled bedforms around the mines, which affect local bottom morphodynamics and are not accounted for in the model, an issue currently being addressed by the modelers. This paper focuses specifically on two instrumented mines: an acoustic mine located in fine sand and an optical instrumented mine located in coarse sand. ?? 2007 IEEE.

  20. 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....

  1. 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.

  2. 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).

  3. Simrad EM300 multibeam backscatter data from portions of the banktop and bank edge environments at Kure Atoll, Hawaii, USA

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Kure Atoll, Northwestern Hawaiian Islands, USA. These data provide coverage between 0 and 2000...

  4. CRED Simrad em300 multibeam backscatter data from the islands and banks in the Mariana archipelago, 2007.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of the Mariana archipelago between the U.S. Territory of Guam and Uracas Island in the Commonwealth...

  5. Monitoring of the nuclear submarine Komsomolets

    Energy Technology Data Exchange (ETDEWEB)

    Heldal, Hilde E.; Flo, Janita K.; Liebig, Penny L. [Institute of Marine Research, P. O. Box 1870 Nordnes, N-5817 Bergen (Norway); Gaefvert, Torbjoern; Rudjord, Anne Liv [Norwegian Radiation Protection Authority, P.O. Box 55, N-1332 Oesteraas (Norway); Gwynn, Justin P. [Norwegian Radiation Protection Authority, The Fram Centre, N-9296 Tromsoe (Norway)

    2014-07-01

    The Soviet nuclear submarine Komsomolets sank on the 7 April 1989, 180 km southwest of Bear Island in the Norwegian Sea to a depth of about 1655 m. The submarine contains one nuclear reactor containing long-lived radionuclides such as cesium-137 ({sup 137}Cs) along with other fission and activation products, in addition to 2 mixed uranium/plutonium nuclear warheads containing weapons grade plutonium. Although several model studies have shown that a radioactive leakage from Komsomolets will have insignificant impact on fish and other marine organisms, there are still public concerns about the condition of the submarine and the potential for radioactive leakage. In order to document the contamination levels and to meet public concerns, monitoring of radioactive contamination in the area adjacent to the submarine has been ongoing since 1993. Samples of bottom seawater and sediments have been collected annually by the Institute of Marine Research (IMR) and have been analysed for {sup 137}Cs and plutonium-239,240 ({sup 239,240}Pu). So far, activity concentrations in the samples have been comparable to levels found in other samples from the Norwegian and Barents Seas. During sampling from R/V 'G. O. Sars' in April 2013, an area of about 1 km{sup 2} of the seabed around Komsomolets was mapped to precisely locate the submarine using a Kongsberg EM302 multibeam echo sounder, a Simrad EK60 single beam echo sounder and an Olex 3D bottom-mapping system. For sediment sampling, a Simrad MST342 mini-transponder was attached to a Smoegen box corer to allow for precise positioning of the corer. With the aid of the Kongsberg HiPAP (High Precision Acoustic Positioning) system, 4 box cores were collected around the submarine at a distance of 10 to 20 m. In addition, one box core was collected from a reference station about 100 m upstream of the submarine. Surface sediments and sediment cores were collected from the box cores taken at each sampling location. Sediment cores

  6. 77 FR 61401 - Notice of Availability of Government-Owned Inventions; Available for Licensing

    Science.gov (United States)

    2012-10-09

    ... BRIDGE CRANE FOR SHIPPING CONTAINERS//Patent No. 7,637,224: COMMAND INFLATABLE BOAT STOPPING BARRIER... VEHICLES//Patent No. 7,721,666: HULL-MOUNTED LINE RETRIEVAL AND RELEASE SYSTEM//Patent No. 7,721,669... CRANE FOR SHIPPING CONTAINERS// Patent No. 7,730,843: HULL-MOUNTED LINE RETRIEVAL AND RELEASE SYSTEM...

  7. AFSC/RACE/GAP/vonSzalay: The Eastern Bering Sea Shelf, Gulf of Alaska, and Aleutian Islands Simrad ES 60 Acoustic Data Collected on Bottom Trawl Surveys

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Calibrated midwater and bottom backscatter data collected continuously with ES-60 echosounders throughout the bottom trawlsurvey period, continuing a time series of...

  8. 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...

  9. CRED Simrad em300 multibeam backscatter data of Jarvis 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 Jarvis Atoll, Pacific Island Areas, Central Pacific. These...

  10. CRED Simrad em300 multibeam backscatter data from the slope environment of Swains Island, American Samoa, South Pacific in GeoTIFF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Swains Island, American Samoa. These data provide coverage between 50 and 5000 meters. The...

  11. CRED Simrad em300 multibeam backscatter data from shelf and slope environments at Howland Island, Pacific Remote Island Areas, Central Pacific in netCDF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Howland Island, Pacific Remote Island Areas, Central Pacific. These data provide coverage between...

  12. CRED Simrad em300 multibeam backscatter data of Baker Island, Pacific Remote Island Areas, Central Pacific in netCDF 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 Baker Island, Pacific Island Areas, Central Pacific. These...

  13. CRED Simrad em300 multibeam backscatter data from Kingman Reef, Pacific Remote Island Areas, Central Pacific 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 Kingman Reef, Pacific Island Areas, Central Pacific....

  14. 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...

  15. CRED Simrad em300 multibeam backscatter data of Two Percent Bank (also called Tulaga Seamount), American Samoa with 5 meter resolution

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Two Percent Bank (also called Tulaga Seamount), American Samoa, South Pacific. These data provide...

  16. CRED Simrad EM3002d multibeam backscatter data from portions of the banktop and bank edge environments at Pearl and Hermes Atoll, Hawaii, USA with 30 meter resolution

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Pearl and Hermes Atoll, Northwestern Hawaiian Islands, USA. These data provide coverage between 0...

  17. CRED Simrad em300 multibeam backscatter data of Vailulu'u Seamount, American Samoa 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 Vailulu'u, American Samoa, an active volcano that lies between Ta'u Island and Rose Atoll,...

  18. CRED Simrad em300 multibeam backscatter data of Vailulu'u Seamount, American Samoa 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 Vailulu'u, American Samoa, an active volcano that lies between Ta'u Island and Rose Atoll,...

  19. CRED Simrad EM300 multibeam backscatter data from portions of the banktop and bank edge environments at Pearl and Hermes Atoll, Hawaii, USA with 30 meter resolution

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Pearl and Hermes Atoll, Northwestern Hawaiian Islands, USA. These data provide coverage between 0...

  20. A New Method For Processing Backscatter Imagery Collected By Multibeam Sonars: The HAWAII MR1 Sidescan Sonar Software Suite

    Science.gov (United States)

    Davis, R.; Appelgate, B.

    2003-12-01

    The Hawaii Mapping Research Group of the University of Hawaii has developed and used in-house software to process seafloor acoustic imagery (sidescan sonar) data acquired by its own shallow-towed HAWAII-MR1 phase-difference sidescan bathymetry mapping system, as well as phase-difference sonars operated by other institutions (NAVO SEAMAP-C, LDEO SCAMP, WHOI DSL-120A). During 2003 the HAWAII MR1 software tools were modified to operate on multibeam backscatter data collected by the University of Hawaii research vessel Kilo Moana to test whether the software could improve the quality of the multibeam backscatter and the resulting data products. We found that the MR1 processing tools are effective in eliminating speckle and stripe noise, and cross-track amplitude variability due to angle-varying gain. HMRG software was also used to produce final mosaics of sonar imagery. Once we determined the viability of using the MR1 tools to process Kilo Moana data, we expanded the toolkit to allow operation on data from other multibeam systems as well. HMRG processing software runs on Linux, Unix and Irix platforms. The main processing modules can be run in either graphical or command-line modes. The preferred processing scheme involves using the graphical interface to interactively determine noise filters appropriate for each survey. Once characterized, these filters are then applied in batch processes that run faster than graphical methods allow. Once processing is completed, the HMRG software is used to grid the data and then to assemble individual grids into mosaics. The mosaics can be output as Sun raster files, geotiffs, or Generic Mapping Tools (GMT) grids, which allow the mosaics to be imported into other GIS and charting programs. Here we present results from several recent surveys that used different hull-mounted multibeam systems: 12kHz Sea Beam 2112 data from the US Coast Guard Cutter Healy, 12kHz Simrad EM120 data from deep water surveys aboard the R/V Kilo Moana

  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. 50 CFR 216.270 - Specified activity and specified geographical region.

    Science.gov (United States)

    2010-10-01

    ... frequency active sonar (HFAS) sources for U.S. Navy anti-submarine warfare (ASW), mine warfare (MIW... below (±10 percent): (i) AN/SQS-53 (hull-mounted active sonar)—up to 9885 hours over the course of 5 years (an average of 1977 hours per year) (ii) AN/SQS-56 (hull-mounted active sonar)—up to 2470...

  3. 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...l’Intelllgence Artificial- Is. La planification des missions. Is gestion des ressources sont des domaines on ces techniques sont naturellement

  4. CRED 20m Gridded bathymetry of Nihoa Island, Hawaii, USA (NetCDF format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded bathymetry (20m) of the shelf and slope environments of Nihoa Island, Hawaii, USA. The netCDF includes multibeam bathymetry from the Simrad EM120, Simrad...

  5. CRED 5 m Gridded bathymetry of Brooks Banks, Hawaii, USA (Arc ASCII format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded bathymetry (5m) of the shelf and slope environments of Brooks Banks, Hawaii, USA. The ASCII includes multibeam bathymetry from the Simrad EM300, Simrad...

  6. Multibeam bathymetry and selected perspective views offshore San Diego, California

    Science.gov (United States)

    Dartnell, Peter; Normark, William R.; Driscoll, Neal W.; Babcock, Jeffrey M.; Gardner, James V.; Kvitek, Rikk G.; Iampietro, Pat J.

    2007-01-01

    This set of two posters consists of a map on one sheet and a set of seven perspective views on the other. The ocean floor image was generated from multibeam-bathymetry data acquired by Federal and local agencies as well as academic institutions including: - U.S. Geological Survey mapped from the La Jolla Canyon south to the US-Mexico border using a Kongsberg Simrad multibeam echosounder system (MBES) (March - April 1998). Data and metadata available at http://pubs.usgs.gov/of/2004/1221/. - Woods Hole Oceanographic Institution and SCRIPPS Institution of Oceanography mapped the majority of the La Jolla Fan Valley including the sea floor to the north and south of the valley using a Seabeam 2100 MBES. Data available at http://www.ngdc.noaa.gov/mgg/bathymetry/multibeam.html. Survey ID, AT07L09, Chief Scientists, Barrie Walden and Joseph Coburn (April 2002). - California State University, Monterey Bay, mapped Scripps Canyon and the head of La Jolla Canyon using a Reson 8101 MBES (October 2001). Data and metadata available at http://seafloor.csumb.edu/SFMLwebDATA.htm. This work was funded by the California Department of Fish and Game California Coastal Conservancy, San Diego Association of Governments (SANDAG), California Department of Fish and Game, and Fugro Pelagos mapped the nearshore region out to about 35-40 m. - The sea floor within this image that has not been mapped with MBES is filled in with interpreted bathymetry gridded from single-beam data available at http://www.ngdc.noaa.gov/mgg/bathymetry/hydro.html. Depths are in meters below sea level, which is referenced to Mean Lower Low Water.

  7. Under-Ice Operations with AUVS in High Latitudes

    Science.gov (United States)

    Ferguson, J.; Kaminski, C. D.

    2012-12-01

    In 2010 and 2011, ISE Explorer Autonomous Underwater Vehicles (AUV), built for Natural Resources Canada (NRCan), were deployed to Canada's high Arctic. The mission was to undertake under-ice bathymetric surveys supporting Canada's submission under the United Nations Convention on the Law of the Sea (UNCLOS). During these deployments several under-ice records were broken and several new technologies were demonstrated. The NRCan AUV is a 5000 meter depth rated vehicle, with several innovative additions to make it suitable for arctic survey work. Most notable are a depth rated variable ballast system, a 1300 Hz long-range homing system, and under-ice charging and data transfer capabilities. The Explorer's range was extended to approximately 450 km by adding a hull section to accommodate extra batteries. The scientific payload onboard included a Seabird SBE49 Conductivity-Temperature-Depth (CTD) sensor, Knudsen singlebeam echosounder, and a Kongsberg Simrad EM2000 multibeam echosounder. In 2010, operations were conducted from an ice camp near Borden Island (78°14'N, 112°39'W) operating through an ice hole. Following several test missions, the AUV spent 10 days surveying under ice before being successfully recovered. In total, close to 1100 km of under-ice survey was undertaken at depths to 3160 meters. A further set of operations was carried out in August and September 2011 from the Canadian Icebreaker CCGS Louis St. Laurent operating with the American Icebreaker USCGS Healy. Here the operations were much further north to latitudes of 88°30' N and to depths of 3500 meters. In this paper, the 2010 ice camp and the 2011 icebreaker missions are described, with an outline of technology developments that were undertaken, the preparations that were necessary for the success of the missions and finally, the outcome of the missions themselves.

  8. CRED Simrad em3002d multibeam backscatter data from the banktop and bank edge environments at Tutuila, American Samoa, South Pacific with 16 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 Tutuila, American Samoa, South Pacific These data provide coverage between 20 and 5000 meters. The...

  9. CRED Simrad em120 multibeam backscatter data from portions of the banktop and bank edge environments at Maro Reef, Hawaii, USA with 30 meter resolution in Arc ASCII format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Maro Reef, Northwestern Hawaiian Islands, USA. These data provide coverage between 20 and 5000...

  10. CRED Simrad em3002d multibeam backscatter data from the banktop and slope environments of Northeast Bank ("Muli" Seamount), American Samoa with 1 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 Northeast Bank ("Muli" Seamount), American Samoa. These data provide coverage between 20 and 5000...

  11. CRED Simrad em3002d multibeam backscatter data from the banktop and bank edge environments at Tutuila, American Samoa, South Pacific with 1 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 Tutuila, American Samoa, South Pacific These data provide coverage between 20 and 5000 meters. The...

  12. CRED Simrad em300 multibeam backscatter data from portions of the banktop and bank edge environments at Maro Reef, Hawaii, USA 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 Maro Reef, Northwestern Hawaiian Islands, USA. These data provide coverage between 20 and 5000...

  13. CRED Simrad em300 multibeam backscatter data from the banktop and slope environments of Northeast Bank ("Muli" Seamount), American Samoa 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 Northeast Bank ("Muli" Seamount), American Samoa. These data provide coverage between 50 and 5000...

  14. CRED Simrad em3002d multibeam backscatter data from portions of the banktop and bank edge environments at Maro Reef, Hawaii, USA in netCDF format with 1 meter resolution

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of Maro Reef, Northwestern Hawaiian Islands, USA. These data provide coverage between 20 and 5000...

  15. CRED Simrad em300 multibeam backscatter data from portions of the banktop and bank edge environments at Maro Reef, Hawaii, USA 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 Maro Reef, Northwestern Hawaiian Islands, USA. These data provide coverage between 20 and 5000...

  16. CRED Simrad em120 multibeam backscatter data from portions of the banktop and bank edge environments at Maro Reef, Hawaii, USA with 30 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 Maro Reef, Northwestern Hawaiian Islands, USA. These data provide coverage between 20 and 5000...

  17. CRED Simrad em300 multibeam backscatter data from portions of the banktop and bank edge environments at Maro Reef, Hawaii, USA with 30 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 Maro Reef, Northwestern Hawaiian Islands, USA. These data provide coverage between 20 and 5000...

  18. CRED Simrad em3002d multibeam backscatter data from the banktop and bank edge environments at Tutuila, American Samoa, South Pacific with 16 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 Tutuila, American Samoa, South Pacific These data provide coverage between 20 and 5000 meters. The...

  19. CRED Simrad em300 multibeam backscatter data from portions of the banktop and bank edge environments at Maro Reef, Hawaii, USA with 30 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 Maro Reef, Northwestern Hawaiian Islands, USA. These data provide coverage between 20 and 5000...

  20. Divergent Ridge Features on the Juan de Fuca and Gorda Ridges

    Science.gov (United States)

    Eaton, M. E.; Sautter, L.; Steele, M.

    2014-12-01

    Multibeam data collected using a Kongsberg EM122 sonar system on the NOAA ship R/V Marcus G. Langseth led by chief scientist Douglas Toomey (University of Oregon) in 2009 and with a Simrad EM302 sonar system on two NOAA ship Okeanos Explorer cruises led by chief scientists James Gardner (University of New Hampshire) and Catalina Martinez (University of Rhode Island) in 2009 show the morphology of the Juan de Fuca and Gorda Ridges, as well as the Blanco and Mendocino Fracture Zones. These ridges and fracture zones comprise the divergent plate boundary of the eastern edge of the Pacific Plate and the western edges of the Juan de Fuca and Gorda Plates. Both plates are being subducted beneath the western edge of the North American Plate. CARIS HIPS 8.1 software was used to process the multibeam data and create bathymetric images. The ridge axes, located off the coast of Washington and Oregon (USA) adjacent to the Cascadia Basin, indicate obvious signs of spreading, due to the series of faults and rocky ridges aligned parallel to the plate boundaries. Fault and ridge orientations are used to compare the direction of seafloor spreading, and indicate that both the Juan de Fuca Plate and Gorda Plate are spreading in a southeastern direction. Younger ridges from the Gorda Ridge system mapped in the study run parallel to the boundary, however older ridges do not show the same orientation, indicating a change in spreading direction. The presence of hydrothermal vents along the Juan de Fuca Ridge is also evidence of the active boundary, as the vent chimneys are composed of minerals and metals precipitated from the hot water heated by magma from beneath the spreading seafloor. In this study, the data are used to compare and contrast earthquake seismicity and ridge morphologies at a depth range of approximately 762 to 2134 meters. The diverging Pacific, Juan de Fuca, and Gorda Plates along with the San Andreas Fault have potential to increase seismic and volcanic activity around

  1. Real-Time Bathymetry and Backscatter Mosaic Software for Towed and Shipboard Mapping Sonars

    Science.gov (United States)

    Davis, R. B.; Appelgate, T. B.; Johnson, P. D.

    2006-12-01

    The Hawaii Mapping Research Group (HMRG) of the University of Hawaii has developed a bathymetry and backscatter mosaic software package that is suitable for use either in real-time survey operations or non-real- time processing applications. The system was originally developed for use with HMRG's own towed sonar systems but is also compatible with shipboard multibeam systems. It has been operational on R/V Kilo Moana under the supervision of the University's Ocean Technology Group marine science technicians for well over a year in support of that vessel's Kongsberg/Simrad EM120 and EM1002 multibeams. The software grids and renders incoming data in geo-referenced chart-like displays. Data are typically processed in three operator-selectable resolutions limited only by the processing and storage capabilities of the Linux- or Unix-based host computer system. A master navigation chart shows survey tracklines and swath coverage -- from this chart the user can simultaneously open multiple mosaic views into the underlying bathymetry and backscatter datasets with independent resolutions and display properties (e.g., contour color key and interval for bathymetry, grayscale mapping for backscatter, region of interest, etc.) All displays are optimized for quick pan and zoom operations and include on-screen interface control features which permit numerous display parameters to be rapidly changed. All mosaic views, as well as the master navigation display, can be updated in real-time as new data are supplied by the mapping instrument and can also display a background reference dataset for comparison with incoming instrument data. The software also includes survey-planning features which permit new survey waypoints to be generated interactively with reference to incoming and/or historical background data. Aboard R/V Kilo Moana a pair of dual-monitor computer systems, one for the EM120 and one for the EM1002, are available for the processing and display of incoming data from

  2. Examination of methane ebullition in a Swiss hydropower reservoir

    Science.gov (United States)

    DelSontro, T.; Ostrovsky, I.; Eugster, W.; McGinnis, D. F.; Wehrli, B.

    2012-04-01

    Ebullition is one of the most important methane emission pathways from inland water bodies, yet the stochastic nature of ebullition complicates its monitoring. Therefore, a bubble-calibrated 120 kHz split-beam echosounder (Simrad EK60, Kongsberg Maritime) was utilized to survey the active ebullition area of a small temperate hydropower reservoir (Lake Wohlen, Switzerland), which is known for intense methane bubble release in summer. The performed bubble size calibration agreed well with the literature and the presented hydroacoustic technique to estimate methane bubble flux in the presence of non-bubble targets was determined to be the most appropriate post-processing method for this reservoir. The acoustically-determined average methane ebullition flux from the sediment to the water column from seven campaigns was 580 mg CH4 m-2 d-1 (range, 130 to 1450). Bubble size distribution, which mostly included 1 to 20 mm diameter bubbles, was strongly related to the magnitude of sediment ebullition flux. The bubble size distribution is an important consideration when calculating the resulting surface efflux using a bubble dissolution model. Using the Sauter mean diameter to represent the volume to surface area to volume ratio of the bubble size distribution in the bubble model resulted in an average atmospheric emission of 490 mg CH4 m-2 d-1. The spatially-averaged data and the standard deviation from seven sampling campaigns revealed areas of 'high' and 'low' ebullition fluxes that seemed to correlate to geomorphology of the reservoir, which still contains the former river channel. The hydroacoustic flux estimates were compared with other methods of methane flux assessments used simultaneously: the traditional chamber method and the eddy covariance technique combined with spectrometer methane measurements (Fast Methane Analyzer, Los Gatos Research). Chamber measurements on all but one day were higher than the hydroacoustic survey results (but within the same order of

  3. Extended Analysis of the PhilSea10 Data Set from the Western Tropical Pacific and Transitioning Results to the Operational Navy

    Science.gov (United States)

    2015-09-30

    temperature to 4400 m depth. The UNOLS vessels used to conduct the work operated hull -mounted ADCPs throughout the many cruises to the area. Several...via officer-students and faculty there. RELATED PROJECTS Peter Worcester, Scripps Institution of Oceanography, project leader John Colosi, Naval

  4. 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

  5. 50 CFR 216.170 - Specified activity and specified geographical region.

    Science.gov (United States)

    2010-10-01

    ...-frequency active sonar (MFAS) and high frequency active sonar (HFAS) sources for U.S. Navy anti-submarine warfare (ASW) training in the amounts indicated below (±10 percent): (i) AN/SQS-53 (hull-mounted sonar)—up to 6420 hours over the course of 5 years (an average of 1284 hours per year) (ii) AN/SQS-56...

  6. Multibeam Sonar Data since 2003 - Cruise Metadata (NOAA Ship Hi'ialakai and R/V AHI)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam sonar data have collected for selected U.S. locations in the Pacific using a RESON 8101ER multibeam sonar, Kongsberg 300 kHz EM3002D, and a Kongsberg 30...

  7. Instrumented Full Scale Tests of a Drifting Buoy and Drogue

    Science.gov (United States)

    1975-12-01

    of very high accuracy (better than 200 feet) owing to the phase-tracking system employed. Both an automatic Epsco and a Simrad/Internav Loran C system...from.the output of a Simrad/Internav LORAN C navi- gator. A similar Epsco system was also employed while coupled to a separate antenna. The Epsco unit gave

  8. Multibeam Bathymetric Gridded Data for selected U.S. locations in the Pacific since 2003

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded bathymetry for selected U.S. locations in the Pacific. The netCDF and Arc ASCII grids include multibeam bathymetry from the Simrad EM300, Simrad EM3002D, and...

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

    National Research Council Canada - National Science Library

    Lundmark PO; Luraas K

    2017-01-01

    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...

  10. 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...

  11. 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...

  12. NOAA TIFF Image - 1 m Backscatter Mosaic of Bajo de Cico, Puerto Rico, Project NF-07-06, 2007, UTM 19 NAD83

    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)...

  13. 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...

  14. 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...

  15. 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)...

  16. 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...

  17. 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...

  18. 3D free-air gravity anomaly modeling for the Southeast Indian Ridge

    Science.gov (United States)

    Girolami, Chiara; Heyde, Ingo; Rinaldo Barchi, Massimiliano; Pauselli, Cristina

    2016-04-01

    In this study we analyzed the free-air gravity anomalies measured on the northwestern part of the Southeast Indian Ridge (hereafter SEIR) during the BGR cruise INDEX2012 with RV FUGRO GAUSS. The survey area covered the ridge from the Rodriguez Triple Junction along about 500 km towards the SSE direction. Gravity and magnetic data were measured along 65 profiles with a mean length of 60 km running approximately perpendicular to the ridge axis. The final gravity data were evaluated every 20 seconds along each profile. This results in a sampling interval of about 100 m. The mean spacing of the profiles is about 7 km. Together with the geophysical data also the bathymetry was measured along all profiles with a Kongsberg Simrad EM122 multibeam echosounder system. Previous studies reveal that the part of the ridge covered by the high resolution profiles is characterized by young geologic events (the oldest one dates back to 1 Ma) and that the SEIR is an intermediate spreading ridge. We extended the length of each profile to the area outside the ridge, integrating INDEX2012 high resolution gravity and bathymetric data with low resolution data derived from satellite radar altimeter measurements. The 3D forward gravity modeling made it possible to reconstruct a rough crustal density model for an extended area (about 250000 km2) of the SEIR. We analyzed the gravity signal along those 2D sections which cross particular geological features (uplifted areas, accommodation zones, hydrothermal fields and areas with hints for extensional processes e.g. OCCs) in order to establish a correlation between the gravity anomaly signal and the surface geology. We started with a simple "layer-cake" geologic model consisting of four density bodies which represent the sea, upper oceanic crust, lower oceanic crust and the upper mantle. Considering that in the study area the oceanic crust is young, we did not include the sediment layer. We assumed the density values of these bodies considering

  19. A Study of Approval Plans and the Government’s Ability to Contract for Them under the Federal Acquisition Regulation (FAR)

    Science.gov (United States)

    1989-12-01

    along with procedural methods for implementing approval plans under current Department of Defense regulations. NTFIS GRASA DTIC TAB0 Just Ifced1 By...with loshiba MAP 1988 Corporation or Kongsberg Vapenfabrikk.- OfferorS Representation 52.225-17027 Restriction on Contracting with Toshiba MAR 1988... Corporation or Kongsberg Vapenfabrikk 52.227-7031( P Data Requirements APR 1912 52-232-7007( P Progress Payments - Alternate I OCT 1916 52.233-100( P

  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. MONT95C - Bathymetry contours of the southern Monterey Bay area between Moss Landing and Monterey, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The bathymetric grids and derived contours are from data collected by the USGS with a multibeam (Simrad EM1000) sidescan sonar system in the southern Monterey Bay...

  2. 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...

  3. Tracklines of a multibeam survey of the sea floor offshore of Fire Island Inlet, New York, in 1998 (polyline shapefile, geographic, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000...

  4. Grid of the sea-floor bathymetry offshore of Fire Island Inlet, New York, in 1998 (3-m resolution Esri binary grid, Mercator, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000...

  5. GeoTIFF image of the backscatter intensity of the sea floor offshore of Moriches Inlet, New York, in 1998 (3-m resolution, Mercator, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000...

  6. GeoTIFF image of the backscatter intensity of the sea floor offshore of Fire Island Inlet, New York, in 1998 (3-m resolution, Mercator, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000...

  7. GeoTIFF image of shaded-relief bathymetry of the sea floor southwest of Montauk Point, New York, in 1998 (3-m resolution, Mercator, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000...

  8. GeoTIFF image of the backscatter intensity of the sea floor offshore of Shinnecock Inlet, New York, in 1998 (3-m resolution, Mercator, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000...

  9. GeoTIFF image of shaded-relief bathymetry of the sea floor offshore of Fire Island Inlet, New York, in 1998 (3-m resolution, Mercator, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000...

  10. GeoTIFF image of shaded-relief bathymetry, colored by backscatter intensity, of the sea floor southwest of Montauk Point, New York, in 1998 (3-m resolution, Mercator, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000...

  11. Grid of the sea-floor bathymetry offshore of Shinnecock Inlet, New York, in 1998 (3-m resolution Esri binary grid, Mercator, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000...

  12. Tracklines of a multibeam survey of the sea floor southwest of Montauk Point, New York, in 1998 (polyline shapefile, geographic, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000...

  13. GeoTIFF image of the backscatter intensity of the sea floor southwest of Montauk Point, New York, in 1998 (3-m resolution, Mercator, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000...

  14. Tracklines of a multibeam survey of the sea floor offshore of Shinnecock Inlet, New York, in 1998 (polyline shapefile, geographic, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000...

  15. GeoTIFF image of shaded-relief bathymetry, colored by backscatter intensity, of the sea floor offshore of Moriches Inlet, New York, in 1998 (3-m resolution, Mercator, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000...

  16. Grid of the sea-floor bathymetry offshore of Moriches Inlet, New York, in 1998 (3-m resolution Esri binary grid, Mercator, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000...

  17. Grid of the sea-floor bathymetry southwest of Montauk Point, New York, in 1998 (3-m resolution Esri binary grid, Mercator, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000...

  18. GeoTIFF image of shaded-relief bathymetry, colored by backscatter intensity, of the sea floor offshore of Shinnecock Inlet, New York, in 1998 (3-m resolution, Mercator, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000...

  19. GeoTIFF image of shaded-relief bathymetry of the sea floor offshore of Shinnecock Inlet, New York, in 1998 (3-m resolution, Mercator, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000...

  20. GeoTIFF image of shaded-relief bathymetry of the sea floor offshore of Moriches Inlet, New York, in 1998 (3-m resolution, Mercator, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000...

  1. Tracklines of a multibeam survey of the sea floor offshore of Moriches Inlet, New York, in 1998 (polyline shapefile, geographic, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000...

  2. GeoTIFF image of shaded-relief bathymetry, colored by backscatter intensity, of the sea floor offshore of Fire Island Inlet, New York, in 1998 (3-m resolution, Mercator, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000...

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 5-m interval contours of smoothed multibeam bathymetry of Massachusetts Bay (MB_5MCTR9X9.SHP, Geographic, NAD83)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The U.S. Geological Survey has conducted geologic mapping to characterize the sea floor offshore of Massachusetts. The mapping was carried out using a Simrad Subsea...

  11. 10-m interval contours of smoothed multibeam bathymetry of Massachusetts Bay (MB_10MCTR9X9.SHP, Geographic, NAD83)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The U.S. Geological Survey has conducted geologic mapping to characterize the sea floor offshore of Massachusetts. The mapping was carried out using a Simrad Subsea...

  12. 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...

  13. 10-m resolution image of shaded relief multibeam bathymetry in Massachusetts Bay, colored by water depth (MB_BATHYCLR10M.TIF)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The U.S. Geological Survey has conducted geologic mapping to characterize the sea floor offshore of Massachusetts. The mapping was carried out using a Simrad Subsea...

  14. 10-m resolution gray-scale image of multibeam backscatter intensity in Massachusetts Bay (MB_BACKGS10M.TIF)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The U.S. Geological Survey has conducted geologic mapping to characterize the sea floor offshore of Massachusetts. The mapping was carried out using a Simrad Subsea...

  15. 10-m resolution gray-scale image of multibeam bathymetry in Massachusetts Bay (MB_BATHYGS10M.TIF)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The U.S. Geological Survey has conducted geologic mapping to characterize the sea floor offshore of Massachusetts. The mapping was carried out using a Simrad Subsea...

  16. 10-m resolution image of shaded relief multibeam bathymetry in Massachusetts Bay, pseudocolored by backscatter intensity (MB_BACKPC10M.TIF)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The U.S. Geological Survey has conducted geologic mapping to characterize the sea floor offshore of Massachusetts. The mapping was carried out using a Simrad Subsea...

  17. 10-m resolution image of shaded relief multibeam bathymetry in Massachusetts Bay (MB_SRELIEF10M.TIF)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The U.S. Geological Survey has conducted geologic mapping to characterize the sea floor offshore of Massachusetts. The mapping was carried out using a Simrad Subsea...

  18. 10-m resolution grid of multibeam bathymetry in Massachusetts Bay (MB_BATHY10M)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The U.S. Geological Survey has conducted geologic mapping to characterize the sea floor offshore of Massachusetts. The mapping was carried out using a Simrad Subsea...

  19. Gridded bathymetry of French Frigate Shoals, Hawaii, USA - Arc ASCII format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded bathymetry (5m) of the shelf environment of French Frigate Shoals, Hawaii, USA. The ASCII includes multibeam bathymetry from the Simrad EM3002d, and Reson...

  20. Directional properties of an 18-KHZ transducer: Proprietes directionnelles d'un transducteur 18 KHZ

    National Research Council Canada - National Science Library

    Foote, K.G

    1993-01-01

    Several theoretical measures of directivity are given for an 18-kHz transducer that is used in both single-beam and split- beam applications, namely the SIMRAD transducer type 18-11 in the single-beam variant...

  1. MONT95C - Bathymetry contours of the southern Monterey Bay area between Moss Landing and Monterey, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The bathymetric grids and derived contours are from data collected by the USGS with a multibeam (Simrad EM1000) sidescan sonar system in the southern Monterey Bay...

  2. 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...

  3. 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...

  4. Integrating Seakeeping in the Design of Semi-Displacement and Displacement Monohulls

    Science.gov (United States)

    2010-06-01

    Speed module which has the ability to calculate residual resistance. The hull used was a 33 ft YP, the same hull used by Roger Compton in his...VISTAR IM 405 IR weapons control system  2 – Sperry RASCAR; E/F/I/J-band surface search radars  1 – Wesmar; hull mounted active high frequency hull...Resistance of a Systematic Series of Semiplaning Transom-Stern Hulls. Compton, Roger H. 4, s.l. : Society of Naval Architects and Marine Engineers, 1986

  5. Acoustic characterization of continental shelf seafloor and benthic habitats using single and multi-beam backscatter data

    Digital Repository Service at National Institute of Oceanography (India)

    Haris, K.; Chakraborty, B.

    employing multi-beam echo- sounder (MBES) and dual-frequency single-beam echo-sounder (SBES) operable at 95 kHz and 33/210 kHz, respectively [5]. The information cataloged is then utilized to characterize the seafloor and related benthic habitat off Goa... of the western continental shelf of India (Fig. 1a) with calibrated SBES and MBES. The dual-frequency (33 and 210 kHz) echo-envelope data were acquired using a hull- mounted normal incidence RESON-NS 420 SBES. Meanwhile, 95 kHz MBES data were acquired using...

  6. Terminal Homing for Autonomous Underwater Vehicle Docking

    Science.gov (United States)

    2016-06-01

    the necessary lifts forces to steer the vehicle. For the REMUS vehicle this sufficient flow roughly equates to 2–3 knots of headway as it attempts to...Submarine Technology Battle. Chula Vista, CA: American Scientific, 1986. [5] REMUS Operations and Maintenance Manual. Kongsberg, Norway: Kongberg

  7. 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....

  8. 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...

  9. 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...

  10. 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...

  11. 78 FR 32469 - Investigations Regarding Eligibility To Apply for Worker Adjustment Assistance

    Science.gov (United States)

    2013-05-30

    .../14/13 05/10/13 Corporation (Union). 82732 Harding Marketing Inc. San Jose, CA 05/14/13 05/02/13...). Stamford, CT 05/14/13 05/06/13 82735 Kongsberg Automotive (State/ Benton, LA 05/14/13 05/03/13 One-Stop...

  12. European Scientific Notes, Volume 38, Number 9.

    Science.gov (United States)

    1984-09-01

    for the atmospheric inter- Centro Comune di Ricerca, 1-21020 Ispra ference in satellite-gathered oceano- (Varese), Italy; phone (010-39-332) graphic... comercially . Simrad surveillance applications, primarily for also plans to become more involved with use on small boats (down to 150-ton yes- sub-bottom

  13. 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...

  14. 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...

  15. Power control system

    OpenAIRE

    Kolgrov, Frode; Sandberg, Christian; Grøterud, Erlend; Fjelltun, Lars O.; Numme, Peder

    2012-01-01

    Oppgaven omhandler å realisere et automasjonssystem med brukergrensesnitt, for energibalansering og regulering av energiproduksjon ved en vindturbinpark, kombinert med et pumpekraftverk. Kraftverkene er via en lukket forsyningssløyfe tilkoblet en by, som til enhver tid skal forsynes med den energimengde som etterspørres. Balanseringen av produksjon, pumpelagring av vann og forbruk er essensen i oppgaven, og dette er realisert ved bruk av Kongsberg Maritimes automasjonssoftwa...

  16. 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.

  17. Acoustic imaging of the passage of turbidity currents and associated hydraulic jumps on underlying cyclic step bedforms. Squamish, BC

    Science.gov (United States)

    Hughes Clarke, J. E.

    2013-12-01

    Active channelized turbidity currents have been repeatedly imaged in 60m of water on the Squamish prodelta. Previously in 2011 and 2012, the prodelta has been repetitively surveyed on daily and hourly timescales and is thus known to exhibit trains of bedforms along the channel floors that resemble cyclic steps that migrate upslope intermittently. Beyond the channel mouths, clear turbidity current flows had previously been detected using a seabed mounted ADCP. In order to directly observe the passage of the flow in the channelized section of the prodelta, in June 2013 a vessel was moored using 4 anchors directly above one of the channels. The vessel operated two hull-mounted single beam sonars at 28 and 200 kHz and a multibeam sonar at 95 kHz, all imaging a near stationary point or swath within or across the channel. In addition a 1200 kHz ADCP was suspended 12m above the seabed and two 500 kHz imaging multibeams were suspended 10m above the channel floor. One of the suspended multibeams was oriented facing upslope examining a 150m range, 120 degree, plan view sector of the channel. The second suspended multibeam was oriented downward to derive a ~30m long along-track section over the length of one of the bedforms. A mechanically dipped CTD and optical backscatter probe was lower repeatedly directly into the active flows until it touched the seabed at about one minute periods. Over a period of 5 days, between 1 and 7 discrete flows per day were monitored passing by within one hour of low water. Their head velocities ranged from ~ 0.5 to 2.5m/s and their thicknesses were generally in the 3-5m range. Looking upstream in plan view, the lobate head of the approaching flows could be seen to be constricted to specific talwegs within the channel floor and rise up and over successive cyclic step bedforms. The higher velocity flows exhibit clear turbulent eddies on their upper surface. The duration of the high velocity component of the flow rarely lasted for more than a few

  18. Proposal for a Joint NASA/KSAT Ka-band RF Propagation Terminal at Svalbard, Norway

    Science.gov (United States)

    Volosin, Jeffrey; Acosta, Roberto; Nessel, James; McCarthy, Kevin; Caroglanian, Armen

    2010-01-01

    This slide presentation discusses the placement of a Ka-band RF Propagation Terminal at Svalbard, Norway. The Near Earth Network (NEN) station would be managed by Kongsberg Satellite Services (KSAT) and would benefit NASA and KSAT. There are details of the proposed NASA/KSAT campaign, and the responsibilities each would agree to. There are several reasons for the placement, a primary reason is comparison with the Alaska site, Based on climatological similarities/differences with Alaska, Svalbard site expected to have good radiometer/beacon agreement approximately 99% of time.

  19. 100 años investigando el mar. El IEO en su centenario (1914-2014).

    OpenAIRE

    Vela Olmo, C. (Carmen); Casado, S.; Lozano Soldevilla, G. (Gonzalo); Lloris, D.; Acosta-Yepes, J. (Juan); Armas Pérez, D. (Demetrio); Balguerías-Guerra, E. (Eduardo); Corral-Estrada, J. (Jerónimo); Díaz-Guerrero, J.I. (José Ignacio); Fernández García,A.; García-Fernández, M.J. (María Jesús); García-Soto, C. (Carlos); Lago-de-Lanzós-y-Tomás, A. (Ana); Pérez-de-Rubín-y-Feigl, J. (Juan); Llinás González, O. (Octavio)

    2014-01-01

    Se trata de un libro que pretende divulgar a la sociedad las principales investigaciones multidisciplinares llevadas a cabo por el Instituto Español de Oceanografía durante su primer siglo de vida, y dar a conocer la historia del organismo, de su Sede Central y de los nueve centros oceanográficos repartidos por los litorales mediterráneo y atlántico, en la península y archipiélagos. Kongsberg 200 Postprint

  20. Propagation and Source Parameters from Long-Period High-Gain Seismographs

    Science.gov (United States)

    1975-05-01

    Ellat Israel F8K Fairbanks Alaska TLO Toledo Spain KON Kongsberg Norway ALQ AlbuQuerque New Mexico Location Elevetion Meters Ul’WoON...Rodriguez-Portugal, C. and A. Udfas. 1972. Estudio del me- canismo y determinaci6n de los parametros dinimicos del foco del terremoto de Azores...290S-6890E EIL TLO F. mode Indian Ocean 16-Sep-72 09-14-34 1592^-9692W TLO EIL F. mode Mexico 23-Dec-72 06-29-42 1294N-8691W TLO EIL F, mode

  1. 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.

  2. Mapeo del fondo marino en el borde de la plataforma continental y talud de la Zona Económica Exclusiva (ZEE) uruguaya

    OpenAIRE

    Mello, C.; López-Orrego, G.

    2011-01-01

    Se analizaron los datos hidroacústicos obtenidos con la ecosonda multihaz Simrad EM-302 a bordo del B/O Miguel Oliver en la campaña 01-2010 durante enero-febrero de 2010. El objetivo fue mapear el fondo oceánico de parte de la plataforma y talud de la Zona Económica Exclusiva (ZEE) uruguaya. El procesamiento fue realizado mediante los softwares libres MB-System y GRASS GIS. Con los datos corregidos se obtuvieron grillas de 3 X 3 m para describir las formaciones del fondo y de 1/8m...

  3. Flare-Shaped Acoustic Anomalies in the Water Column Along the Ecuadorian Margin: Relationship with Active Tectonics and Gas Hydrates

    Science.gov (United States)

    Michaud, Francois; Proust, Jean-Noël; Dano, Alexandre; Collot, Jean-Yves; Guiyeligou, Grâce Daniella; Hernández Salazar, María José; Ratzov, Gueorgui; Martillo, Carlos; Pouderoux, Hugo; Schenini, Laure; Lebrun, Jean-Frederic; Loayza, Glenda

    2016-10-01

    With hull-mounted multibeam echosounder data, we report for the first time along the active Ecuadorian margin, acoustic signatures of water column fluid emissions and seep-related structures on the seafloor. In total 17 flare-shaped acoustic anomalies were detected from the upper slope (1250 m) to the shelf break (140 m). Nearly half of the flare-shaped acoustic anomalies rise 200-500 m above the seafloor. The base of the flares is generally associated with high-reflectivity backscatter patches contrasting with the neighboring seafloor. We interpret these flares as caused by fluid escape in the water column, most likely gases. High-resolution seismic profiles show that most flares occur close to the surface expression of active faults, deformed areas, slope instabilities or diapiric structures. In two areas tectonic deformation disrupts a Bottom Simulating Reflector (BSR), suggesting that buried frozen gas hydrates are destabilized, thus supplying free gas emissions and related flares. This discovery is important as it opens the way to determine the nature and origin of the emitted fluids and their potential link with the hydrocarbon system of the forearc basins along the Ecuadorian margin.

  4. 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.

  5. Constraints on Methane Distribution from Acoustic Profiles of Shallow Sediments Across the Alaska Shelf

    Science.gov (United States)

    Wood, W. T.; Hart, P. E.; Greinert, J.; de Batist, M. A.; Rose, K.; Coffin, R. B.

    2009-12-01

    In September of 2009 the U. S. Naval Research Laboratory, U. S. Dept of Energy, and Royal Netherlands Institute for Sea Research conducted piston coring, acoustic profiling, and water sampling on the Alaskan Arctic shelf from the U. S. Coast Guard icebreaker Polar Sea, as part of the MITAS (Methane In The Arctic Shelf) project. The overall project objective is to determine the role of methane in arctic shelf processes by determining the source, distribution, and concentration of shallow (0-30m methane accumulations as well as active and potential methane seeps along selected transects across and along the Alaskan Beaufort Sea shelf. The specific objective of the acoustic program is to delineate gas (methane) by mapping bubble release into the water column (flare detection), and free gas indications as acoustic blanking and gas fronts in the sediment. The data consist of 3.5 kHz, 12 kHz profiles acquired using hull-mounted transducers on the Polar Sea, in conjunction with 3.5 kHz sub-bottom profiler and 180 kHz multi-beam data acquired from the Polar Sea's ASB (Arctic Service Boat). Acoustic profiles and images, as well as preliminary interpretations are discussed in the presentation.

  6. 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.

  7. Strategies, methods, and technologies adopted on the R.V. G.O. Sars MAR-ECO expedition to the Mid-Atlantic Ridge in 2004

    Science.gov (United States)

    de L. Wenneck, T.; Falkenhaug, T.; Bergstad, O. A.

    2008-01-01

    The MAR-ECO project aimed to gather information on mid-ocean ridge macro- and megafaunal assemblages and their distribution patterns in relation to the abiotic environment, and the target area extended from Iceland to the Azores, comprising waters associated with the Mid-Atlantic Ridge. Strategies and methods adopted on the 2004 international expedition on the R.V. G.O. Sars and M.S. Loran were selected in order to maximise data and sample collection in all pelagic and benthic habitats to a maximum depth of 3500 m, spanning the organism size range from mm to metres. The approach selected was to combine (1) Continuous sampling along the ship's track; (2) Point observations using a pre-defined set of samplers at pre-determined sites; and (3) Opportunistic sampling to study particular phenomena or carry out exceptional tasks. A wide range of nets and mid-water and bottom trawls were mobilised in order to collect biological samples. Hull-mounted, lowered and towed optical and acoustical instruments collected data and images. Two remotely operated vehicles (ROVs) were used for pelagic and demersal studies, and moored echosounders and cameras on benthic landers collected vessel-independent information. Observation of whales and seabirds were made from a custom-built observation area on top of the wheelhouse. Using a range of technologies from the same platform efficiently provided comprehensive results and enhanced the potential for new discoveries at the organism, community, and ecosystem levels.

  8. Progress in the development of shallow-water mapping systems

    Science.gov (United States)

    Bergeron, E.; Worley, C.R.; O'Brien, T.

    2007-01-01

    The USGS (US Geological Survey) Coastal and Marine Geology has deployed an advance autonomous shallow-draft robotic vehicle, Iris, for shallow-water mapping in Apalachicola Bay, Florida. The vehicle incorporates a side scan sonar system, seismic-reflection profiler, single-beam echosounder, and global positioning system (GPS) navigation. It is equipped with an onboard microprocessor-based motor controller, delivering signals for speed and steering to hull-mounted brushless direct-current thrusters. An onboard motion sensor in the Sea Robotics vehicle control system enclosure has been integrated in the vehicle to measure the vehicle heave, pitch, roll, and heading. Three water-tight enclosures are mounted along the vehicle axis for the Edgetech computer and electronics system including the Sea Robotics computer, a control and wireless communications system, and a Thales ZXW real-time kinematic (RTK) GPS receiver. The vehicle has resulted in producing high-quality seismic reflection and side scan sonar data, which will help in developing the baseline oyster habitat maps.

  9. Investigating Hydrocarbon Seep Environments with High-Resolution, Three-Dimensional Geographic Visualizations.

    Science.gov (United States)

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

    2015-12-01

    Detailed photographic imagery and bathymetric maps of the seafloor acquired by deep submergence vehicles such as Autonomous Underwater Vehicles (AUV) and Remotely Operated Vehicles (ROV) are expanding how scientists and the public view and ultimately understand the seafloor and the processes that modify it. Several recently acquired optical and acoustic datasets, collected during ECOGIG (Ecosystem Impacts of Oil and Gas Inputs to the Gulf) and other Gulf of Mexico expeditions using the National Institute for Undersea Science Technology (NIUST) Eagle Ray, and Mola Mola AUVs, have been fused with lower resolution data to create unique three-dimensional geovisualizations. Included in these data are multi-scale and multi-resolution visualizations over hydrocarbon seeps and seep related features. Resolution of the data range from 10s of mm to 10s of m. When multi-resolution data is integrated into a single three-dimensional visual environment, new insights into seafloor and seep processes can be obtained from the intuitive nature of three-dimensional data exploration. We provide examples and demonstrate how integration of multibeam bathymetry, seafloor backscatter data, sub-bottom profiler data, textured photomosaics, and hull-mounted multibeam acoustic midwater imagery are made into a series a three-dimensional geovisualizations of actively seeping sites and associated chemosynthetic communities. From these combined and merged datasets, insights on seep community structure, morphology, ecology, fluid migration dynamics, and process geomorphology can be investigated from new spatial perspectives. Such datasets also promote valuable inter-comparisons of sensor resolution and performance.

  10. Hydroacoustic registration of fish abundance of offshore wind farms. Horns Rev offshore wind farm. Annual report 2004.

    Energy Technology Data Exchange (ETDEWEB)

    Hvidt, C.B.; Bruenner, L.; Reier Knudsen, F.

    2005-05-15

    Elsam Engineering AS has approved the implementation of a project concerning the registration of fish communities in Horns Rev Offshore Wind Farm with use of hydroacoustic methods. In a joint effort, Bio/consult as, Carl Bro as and SIMRAD AS have monitored the fish communities at Horns Rev Offshore Wind Farm using a new hydroacoustic methodology. The new hydroacoustic technique combines the use of scientific sonar acoustics with GPS to determine the density, diversity and location of fish. The objectives of this project were to test the possibility of using hydroacoustic techniques as alternative methods to traditional techniques to assess the fish assemblage inhabiting offshore wind farms and to investigate the possible effect from the wind farm and hard bottom substrates (turbine foundations) on fish abundance. The field study was carried out October 9-10, 2004 and consisted of four horizontal hydroacoustic survey transects each covering impact and reference areas. Transects were surveyed in order to achieve identical impact and reference transect pairs concerning environment, topography and time correspondence. The hydroacoustic equipment consisted of a SIMRAD EK60/EY60 echo sounder with a split-beam transducer (Simrad ES 120-4x10) mounted on a pan and tilt unit, a transceiver, a laptop extended with a GPS-receiver and additional large external hard discs. The raw data files from EK60 were converted to echogram files suitable for the post processing application, Sonar5-Pro. The Sonar5-Pro software makes it possible to filter out echo detections from the surface and the bottom, as well as perform cross filter detection. The validity of the results using the hydroacoustic method is high due to the cross filtering and single target tracking technique. From the hydroacoustic results, no or very little effect from the wind farm or from hard bottom substrates was found on the fish densities at Horns Rev Wind Farm at the time of the survey. The execution of the field

  11. A Sedimentary and Stratigraphic Record of the Deglaciation of the Beaufort Margin, Arctic Ocean

    Science.gov (United States)

    Klotsko, S.; Driscoll, N. W.; Keigwin, L. D.; Rosenblatt, X.

    2016-12-01

    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 four sediment cores will be presented. These records provide insight into the variability of deglacial processes experienced along the margin. They also help constrain the extent of two ice rafted debris (IRD) events captured in the existing grain size data from JPCs 15/27, just east of the Mackenzie trough. These overlapping cores contain two layers that have peaks in grain size around 20 microns compared to the 5 micron average for the core. The grain size peaks correlate to the high amplitude reflectors observed in the seismic CHIRP data, as well as peaks in magnetic susceptibility. These layers also correlate with light δ18O events in the oxygen isotope data. The lower IRD layer occurred 14.5 ka and is interpreted to be enhanced ice discharge from the Amundsen and McClure ice streams. The upper IRD layer is much thicker and started 12.9 ka. This event is interpreted to be massive freshwater discharge from Lake Agassiz that flowed down the Mackenzie and caused the Younger Dryas cold period. The seismic data from the stations around the Mackenzie also record a large sediment package that reaches 7 meters thick at the depocenter. This layer was deposited from 14 to 13.7 ka, reaching sedimentation rates over 8 m/kyr. The large sedimentation event and the IRD events are best observed around the Mackenzie River and extend to JPC 37 in the west and JPC 25 in the east. Farther away from the river trough, other signals dominate the sediment record.

  12. 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.

  13. Oceanographic Conditions in the Canada Basin at the End of Winter during 2014 Recorded by the Scicex Program

    Science.gov (United States)

    Sambrotto, R.; Smethie, W. M., Jr.; Morison, J.; Gossett, J.

    2014-12-01

    Submarines offer a unique sampling capability for the Arctic Ocean. They can rapidly transit to anywhere in the Arctic making continuous measurements of ice draft, sea floor depth, temperature, salinity and other properties. They can also collect water samples for a variety of chemical and biological measurements and can be a valuable component of the Arctic Observing System. An agreement with the US Navy continues scientific measurements on transit legs of submarines crossing the Arctic Ocean as phase II of the SCICEX program that was begun in the 1990s. We present results from this program collected during a period of complete ice cover in the western Arctic in spring 2014 by two submarines. Continuous data were recorded with the hull-mounted CTD along 4 crossings of the Canada Basin totaling over 6500 km. Vertical profiles of temperature and salinity were obtained at multidepth stations where the submarine changed depths and from periodic XCTDs. Fresher, Pacific water dominated the upper 150 m of the Canada Basin, but shoaled significantly across the Makarov Basin and onto the Lomonosov Ridge. Discrete water samples also were collected with a horizontal spacing of about 60 km along track and during 12 multidepth stations with 6 sampling depths in the upper 250 m. The water samples are being measured at shore based labs for oxygen isotopes, nutrients, tritium, helium-3, CFCs, SF6, carbonate system variables, particulate carbon and nitrogen and chlorophyll levels. These results will be presented in the context of the hydrographic measurements to provide a unique view of the biogeochemical and physical state of the western Arctic at the end of winter.

  14. 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.

  15. 海洋调查船动力定位能力分析

    Institute of Scientific and Technical Information of China (English)

    刘铁生; 陈建涛; 刘枫琛; 朱亮亮; 王远飞

    2015-01-01

    文中根据IMCA的相关规范,基于MATLAB语言编写动力定位能力分析程序.以某型海洋调查船为研究对象,计算了不同设计工况下不同方位角时所选用推进器的实际推力与最大推力百分比,并且绘制了动力定位能力曲线,对其定位能力进行了分析.采该分析程序计算结果与Kongsberg Maritime分析报告结果吻合良好,表明该分析程序的可靠性,该分析程序可以为海洋调查船推进器的选型和布置提供依据.

  16. Sensitivity Analysis of Automated Ice Edge Detection

    Science.gov (United States)

    Moen, Mari-Ann N.; Isaksem, Hugo; Debien, Annekatrien

    2016-08-01

    The importance of highly detailed and time sensitive ice charts has increased with the increasing interest in the Arctic for oil and gas, tourism, and shipping. Manual ice charts are prepared by national ice services of several Arctic countries. Methods are also being developed to automate this task. Kongsberg Satellite Services uses a method that detects ice edges within 15 minutes after image acquisition. This paper describes a sensitivity analysis of the ice edge, assessing to which ice concentration class from the manual ice charts it can be compared to. The ice edge is derived using the Ice Tracking from SAR Images (ITSARI) algorithm. RADARSAT-2 images of February 2011 are used, both for the manual ice charts and the automatic ice edges. The results show that the KSAT ice edge lies within ice concentration classes with very low ice concentration or open water.

  17. 国际新闻

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    北美箱纸板需求量下降;ICCA公布2004年瓦楞纸箱行业统计数据;DS Smith销售收入增加;OCC需求量大增;美国纸板价格浮动不大;加拿大纸箱出货量减少;德国LASERCOMB公司成功举办2005年度现场演示会;爱克发销售艾司科公司的包装印刷产品;国际纸业总部将搬迁;SSCC将缩减产量;MBM成为山特维克代理商;Esko-Graphics Kongsberg XL打样机产量突破1000。

  18. KEMAMPUAN TANGKAP JARING TRAWL TERHADAP IKAN DEMERSAL DI PERAIRAN TARAKAN DAN SEKITARNYA

    Directory of Open Access Journals (Sweden)

    Asep Priatna

    2016-03-01

    Fish stock estimation is very important information as basis for developing fisheries. Until now, estimation of demersal fish stock is usually used swept area method by using trawl net fishing. However, there was the problem related to accuracy of fish abundant estimation that is how much the demersal fish could be accurately caught by the trawl net. To solve this problem, an approach estimation of dmersal fish stock using acoustic survey conducted simultaneously with demersal trawl fishing. Research activities were conducted on May, August and November 2012 in Tarakan waters, North Kalimantan using echosounder Simrad EY60-120 kHz and bottom trawl net with 26 m headrope. The result show that the catchability coefficient of trawl net estimated  0,3, it means that the trawl net could be able to catch 30% of demersal fish during swept area trawl fishing.

  19. Sea floor maps showing topography, sun-illuminated topography, and backscatter intensity of the Stellwagen Bank National Marine Sanctuary region off Boston, Massachusetts

    Science.gov (United States)

    Valentine, P.C.; Middleton, T.J.; Fuller, S.J.

    2000-01-01

    This data set contains the sea floor topographic contours, sun-illuminated topographic imagery, and backscatter intensity generated from a multibeam sonar survey of the Stellwagen Bank National Marine Sanctuary region off Boston, Massachusetts, an area of approximately 1100 square nautical miles. The Stellwagen Bank NMS Mapping Project is designed to provide detailed maps of the Stellwagen Bank region's environments and habitats and the first complete multibeam topographic and sea floor characterization maps of a significant region of the shallow EEZ. Data were collected on four cruises over a two year period from the fall of 1994 to the fall of 1996. The surveys were conducted aboard the Candian Hydrographic Service vessel Frederick G. Creed, a SWATH (Small Waterplane Twin Hull) ship that surveys at speeds of 16 knots. The multibeam data were collected utilizing a Simrad Subsea EM 1000 Multibeam Echo Sounder (95 kHz) that is permanently installed in the hull of the Creed.

  20. Measurement of single-fish target strength in the South China Sea

    Institute of Scientific and Technical Information of China (English)

    CHEN Guobao; LI Yongzhen; CHEN Pimao; ZHANG Jun; FANG Lichen; LI Nana

    2012-01-01

    We measured the target strength (TS) of three commercial fish species:whitespotted spinefoot (Siganus canaliculatus),black porgy (Acanthopagrus schlegelii),and creek red bream (Lutjanus argentimaculatus),in the South China Sea.The TS of caged or tethered fish (n=76 total) was measured using a Simrad EY60 portable scientific echosounder at 120 kHz.We evaluated the relationship between TS and total length (TL,cm) for the three species.This is the first attempt to use split-beam acoustics to measure single-fish TS in the South China Sea by Chinese researchers.Our results will improve the accuracy and precision of acoustic abundance estimates of commercially important species and further the development of underwater acoustic survey techniques in fisheries in the South China Sea.

  1. High-Frequency Acoustic Sediment Classification in Shallow Water

    CERN Document Server

    Bentrem, F W; Kalcic, M T; Duncan, M E; Bentrem, Frank W.; Sample, John; Kalcic, Maria T.; Duncan, Michael E.

    2002-01-01

    A geoacoustic inversion technique for high-frequency (12 kHz) multibeam sonar data is presented as a means to classify the seafloor sediment in shallow water (40-300 m). The inversion makes use of backscattered data at a variety of grazing angles to estimate mean grain size. The need for sediment type and the large amounts of multibeam data being collected with the Naval Oceanographic Office's Simrad EM 121A systems, have fostered the development of algorithms to process the EM 121A acoustic backscatter into maps of sediment type. The APL-UW (Applied Physics Laboratory at the University of Washington) backscattering model is used with simulated annealing to invert for six geoacoustic parameters. For the inversion, three of the parameters are constrained according to empirical correlations with mean grain size, which is introduced as an unconstrained parameter. The four unconstrained (free) parameters are mean grain size, sediment volume interaction, and two seafloor roughness parameters. Acoustic sediment cla...

  2. Comparison of Airborne Lidar and Multibeam Bathymetric Data in the Florida Reef Tract Along Broward County

    Science.gov (United States)

    Morton, N. E.; Burd, J. J.

    2003-12-01

    Although large, well-known concentrations of corals are found in deeper waters off Florida's eastern seaboard, most mapping of Florida's coral resources addresses the relatively shallow waters of the Florida Keys. To date, technological limitations precluded mapping corals in these deeper waters. Satellite imaging systems and natural color aerial photography, two mapping mainstays, are generally only effective in Florida waters shallower than 20 meters. Conservation of the northern portion of the Florida reef tract, which parallels the Atlantic coast in Miami-Dade, Broward, and Palm Beach counties, has been hampered by minimal or nonexistent coordinated management, monitoring, and mapping activities. In November 2000, the Simrad EM3000 multibeam system was used to collect data south of Port Everglades. Additionally, the Broward County shore protection project conducted a Laser Airborne Depth Sounder (LADS) survey in 2001. Wavelet analyses performed on overlapping transects of the two data sets compare the accuracy of reef bathymetry and complexity captured in the two data collection projects.

  3. ESTIMASI STOK SUMBER DAYA IKAN DENGAN METODE HIDROAKUSTIK DI PERAIRAN KABUPATEN BENGKALIS

    Directory of Open Access Journals (Sweden)

    Asep Priatna

    2016-06-01

    Full Text Available Perairan Bengkalis termasuk wilayah pengelolaan perikanan Selat Malaka, merupakan kawasan dengan status pemanfaatan tinggi sehingga diperlukan tahapan pemantauan yang intensif dan penelitian potensi sumber daya ikan. Penelitian ini bertujuan untuk mendapatkan nilai estimasi biomassa dan kepadatan stok sumber daya ikan dengan metode akustik. Data kuantitatif yang diperoleh akan menjadi sumber informasi terkini dari kondisi sumber daya ikan di perairan Kabupaten Bengkalis. Penelitian ini dilaksanakan pada bulan Oktober 2009 di perairan Kabupaten Bengkalis yang merupakan bagian dari Selat Malaka. Perangkat akustik yang digunakan adalah split beam echosounder Simrad EY60 dengan frekuensi 120 kHz. Data hasil tangkapan dengan trawl dari jenis ikan pelagis dan demersal yang dominan di perairan ini digunakan untuk memverifikasi data akustik. Estimasi biomassa pada luas daerah 5.433 km2 adalah 9.374 ton dengan kepadatan stok 0,44 ton/km2 untuk ikan pelagis dan 4.441,5 ton dengan kepadatan stok 0,17 ton/km2 untuk ikan demersal.   Bengkalis waters was included in the regional fisheries management of Malacca Strait, having high utilization in fisheries. Therefore intensive monitoring as well as research on fish stock is needed. The aim of the research was to estimate fish biomass and stock density based on acoustic method. The quantitative data are source of current information for fish resources condition in Bengkalis waters. The survey was conducted in October 2009 in Bengkalis waters. Simrad EY60 split beam echosounder with frequency 120 kHz was used for acquisition of acoustic data. Both pelagic and demersal fish as dominant species caught were used for verification acoustic data. The biomass estimation on 5,433 km2 covered area was about 9,374 ton with stock density about 0.44 ton/km2 for pelagic fish, while 4,441.5 ton with stock density about 0.17 ton/km2 for demersal fish.

  4. CHIRP seismic reflection study of falling-stage (forced regressive) sediment wedges on the New Jersey outer continental shelf

    Science.gov (United States)

    Santra, M.; Goff, J.; Ron, S.; Austin, J.

    2007-12-01

    High-resolution (1-12 kHz), deep-towed and hull-mounted CHIRP seismic data were collected on the New Jersey outer shelf in 2001, 2002 and 2006 as part of Office of Naval Research-funded projects. These data have imaged two well-developed, offlapping sedimentary wedges (named outer-shelf wedge and deep-shelf wedge) that are now postulated to have developed on the falling-stage limb of the last glacial cycle, during some time prior to the Last Glacial Maximum (20-22 kyrs BP). These wedges formed atop the high-amplitude, regional R horizon, a complex erosional unconformity that formed about 40,000 years ago. The outer shelf wedge is also characterized in part by an enigmatic, erose boundary separating layered horizons below from a mostly transparent section above. New Jersey shelf wedges appear analogous to forced-regressive units imaged on the Rhone shelf edge, as well as Eocene sections documented from seismic-scale outcrops on Spitsbergen Island. These examples can reach thicknesses up to 100 m on the shelf edge and uppermost slope, but usually thin rapidly downslope. Such wedges represent one of two documented mechanisms involving sand transport across a shelf margin into deeper water settings, the other being a canyonized shelf-edge. Our study will includes analysis of the CHIRP data and, if available, additional ground truth provided by short cores collected in summer 2007 at numerous intra-wedge stratigraphic horizons. Our goals are to understand the external and internal geometry of the wedges and sediment pathways across the paleo-shelf. These data should allow us to characterize margin segments that build during sea-level fall by slope-apron accretion rather than by the formation of channel-levee complexes. The literature is heavily weighted by the latter and their associated canyon systems, but information on shelf-edge attached slope aprons and how they contribute to deep-water sedimentation, and in particular the delivery of clean sands to slope settings

  5. Sedimentological and Stratagraphic Evidence for a Catastrophic Flood Along the Beaufort Margin, Arctic Ocean

    Science.gov (United States)

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

    2014-12-01

    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. Sediment cores were also acquired. The seismic data image an extensive margin-wide drift deposit, which appears to have entered the Beaufort margin from the Mackenzie River. The deposit is thickest on the eastern side of the Mackenzie Delta, near stations 5 and 9. It thins west along the Beaufort margin nearing Barrow Canyon. The deposit also thins to the east, but does not extend as far in this direction. Sediment core Healy1302-JPC15, from station 5 on the Mackenzie slope, was analyzed for grain size using a Laser Diffraction Particle Size Analyzer. These data were compared to the magnetic susceptibility data from the core. Peaks in the susceptibility correlate with increases in grain size, as well as high amplitude reflectors within the drift deposit present in the seismic data. The drift deposit appears to have a diagnostic reflection pattern observed in the seismic data with the base being characterized by a high amplitude reflector that correlates with increased IRD. Above the basal reflectors, an acoustically transparent interval is observed with thicknesses on the order of 7 m near the depocenter; this interval has diminished IRD and radiocarbon dates yield accumulation rates as high as 8 m/ky. The dominant grain size for this interval is ~5 μm. Above the transparent interval is a series of high amplitude reflectors defining the top of the drift deposit. The dominant grain size for the basal and upper high amplitude reflectors reaches ~20 μm. We postulate that the drift deposit was sourced from glacial Lake Agassiz and flowed down the Mackenzie River, entering the Arctic Ocean. It was then entrained by the Beaufort Gyre, migrating clockwise along the margin. Oxygen isotope data reflects the light δO18 signature consistent with a large glacial meltwater input

  6. Fisheries Oceanography in the Virgin Islands: Preliminary Results from a Collaborative Research Endeavor

    Science.gov (United States)

    Smith, R. H.; Gerard, T. L.; Johns, E. M.; Lamkin, J. T.

    2008-05-01

    A multi-species spawning aggregation located on the banks south of St. Thomas includes several economically important fish species, including dog snapper, yellowfin grouper, Nassau grouper, and tiger grouper. Increased fishing pressure on these banks has prompted the Caribbean Fisheries Council to take actions such as seasonally closing fishing grounds and establishing Marine Protected Areas (MPAs). Due to a lack of biological and oceanographic data for the region, these management decisions have been based on professional judgment rather than scientific data. In response to this situation, NOAA scientists from SEFSC and AOML began an interdisciplinary field study in the region in 2007. Research cruises utilize biological sampling techniques such as MOCNESS, neuston, and bongo trawl tows simultaneously with standard physical sampling methods such as CTD/LADCP casts, hull- mounted water velocity measurements, and Lagrangian drifter deployments. The three year project aims to determine how the unprotected banks of the Virgin Islands and surrounding region, the seasonally closed banks and MPAs, and near-shore areas are ecologically linked in terms of larval dispersal, transport, and life history patterns. This collaboration should produce an assessment, based on scientific data, of the effectiveness of Caribbean Research Council management decisions and suggest modifications and improvements to current policy. Additionally, this project will also provide fisheries independent data, and develop ecological indices which can be integrated into stock assessment models. Analysis of data gathered during the project's first research cruise is yielding preliminary results. A total of 26,809 fish larvae were collected from the Grammanik and Red Hind Banks and surrounding regions. Of this total, 585 Serranidae (grouper) and 93 Lutjanidae (snapper) larval specimens were collected. Typical sampling transects included near-shore, shelf-break, and offshore regimes. The most

  7. 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

  8. 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

  9. 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

  10. Multibeam Bathymetry of Haleakala Volcano, Maui

    Science.gov (United States)

    Eakins, B. W.; Robinson, J.

    2002-12-01

    The submarine northeast flank of Haleakala Volcano, Maui was mapped in detail during the summers of 2001 and 2002 by a joint team from the Japan Marine Science and Technology Center (JAMSTEC), Tokyo Institute of Technology, University of Hawaii, and the U.S. Geological Survey. JAMSTEC instruments used included SeaBeam 2112 hull-mounted multibeam sonar (bathymetry and sidescan imagery), manned submersible Shinkai 6500 and ROV Kaiko (bottom video, photographs and sampling of Hana Ridge), gravimeter, magnetometer, and single-channel seismic system. Hana Ridge, Haleakala's submarine east rift zone, is capped by coral-reef terraces for much of its length, which are flexurally tilted towards the axis of the Hawaiian Ridge and delineate former shorelines. Its deeper, more distal portion exhibits a pair of parallel, linear crests, studded with volcanic cones, that suggest lateral migration of the rift zone during its growth. The northern face of the arcuate ridge terminus is a landslide scar in one of these crests, while its southwestern prong is a small, constructional ridge. The Hana slump, a series of basins and ridges analogous to the Laupahoehoe slump off Kohala Volcano, Hawaii, lies north of Hana Ridge and extends down to the Hawaiian moat. Northwest of this slump region a small, dual-crested ridge strikes toward the Hawaiian moat and is inferred to represent a fossil rift zone, perhaps of East Molokai Volcano. A sediment chute along its southern flank has built a large submarine fan with a staircase of contour-parallel folds on its surface that are probably derived from slow creep of sediments down into the moat. Sediments infill the basins of the Hana slump [Moore et al., 1989], whose lowermost layers have been variously back-tilted by block rotation during slumping and flexural loading of the Hawaiian Ridge; the ridges define the outer edges of those down-dropped blocks, which may have subsided several kilometers. An apron of volcaniclastic debris shed from

  11. 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

  12. Seamount subduction and related deformation and seismicity of the continental slope off Manzanillo, Mexico, as evidenced by multibeam data

    Science.gov (United States)

    Bandy, W. L.; Castillo Maldonado, M.; Mortera-Gutierrez, C. A.

    2014-12-01

    The west coast of Mexico presents a complex pattern of deformation related to the convergence and subduction of the Rivera plate beneath the Jalisco Block/North American plate. Previous single beam bathymetric data have evidenced a large bathymetric high at 104.6218oW, 18.7123oN, in the continental slope region off Manzanillo, Mexico. One school of thought held that this high was the offshore extension of the onshore Manzanillo horst, although the two features are offset in a right-lateral sense. Alternatively, given the presence of a large positive magnetic anomaly near the bathymetric high, the high could also be caused by the collision and subsequent subduction of a large seamount. Given that the offset between the two structures was the main evidence for proposing the existence of a forearc sliver in the offshore area of the Jalisco margin, resolving the nature of this bathymetric high is quite important in our attempts to understand the plate kinematics and tectonics of this region. Thus, to better define the deformation pattern associated with the bathymetric high, multibeam bathymetric data (obtained using the Kongsberg EM300 multibeam system), subbottom profiles (obtained using the Kongsberg TOPAS18 system), and total field magnetic data (obtained using the Geometrics G877 marine proton precession magnetometer) were collected in the continental slope region between Manzanillo, Colima, and Chamela, Jalisco, during several cruises of UNAM´s research vessel the B.O. EL PUMA. The morphology and structural deformation patterns obtained in this study indicate very clearly that a large seamount is in the process of subducting beneath the continental slope off Manzanillo. The results also indicate that not only has the seamount uplifted the slope but has resulted in slumping of the area of the slope landward of the seamount. Given these results the proposal of the existence of an independent forearc sliver in the offshore area of the southern Jalisco block needs

  13. 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

  14. Hydroacoustic methodology for detection, localization, and quantification of gas bubbles rising from the seafloor at gas seeps from the eastern Black Sea

    Science.gov (United States)

    Nikolovska, Aneta; Sahling, Heiko; Bohrmann, Gerhard

    2008-10-01

    Detailed acoustic investigation of bubble streams rising from the seafloor were conducted during R/V Meteor cruise M72/3a at a deep submarine hydrocarbon seep environment. The area is located offshore Georgia (eastern part of the Black Sea) at a water depth between 840 m and 870 m. The sediment echosounder Parasound DS-3/P70 was used for detecting bubbles in the water column that causes strong backscatter in the echographs ("flares"). Employing the swath echsounder Kongsberg EM710 flares in the water column were mapped along the entire swath width of approximately 1000 m at high spatial resolution. The exact location of the flares could be extracted manually. Subsequently, the horizontally looking sonar Kongsberg digital telemetry MS1000 mounted on a remotely operated vehicle (ROV) was utilized to quantify the flux of bubbles. A model was developed that is based on the principle of finding the "acoustic mass" in order to quantify the bubble flux at various seeps. The acoustic approach from the backscatter data of the ROV sonar resulted in bubble fluxes in the range of 0.01 to 5.5 L/min (corresponding to 0.037 to 20.5 mol CH4/min) at in situ conditions (˜850 m water depth, ˜9°C). Independent flux estimations using a funnel-shaped device showed that the acoustic model consistently produced lower values but the offset is less than 12%. Furthermore, the deviation decreased with increasing flux rates. A field of bubble streams was scanned three times from different directions in order to reveal the reproducibility of the method. Flux estimations yielded consistent fluxes of about 2 l/min (7.4 mol CH4/min) with variations of less than 10%. Although gas emissions have been found at many sites at the seafloor in a range of geological settings, the amount of escaping gas is still largely unknown. With this study presenting a novel method of quantifying bubble fluxes employing a horizontally looking sonar system, it is intended to contribute to the global effort of better

  15. 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

  16. A Neuroscience Approach in User Satisfaction Evaluation in Maritime Education

    Directory of Open Access Journals (Sweden)

    Maria Lambrou

    2013-09-01

    Full Text Available The evaluation with the use of neuroscience methods and tools of a student’s satisfaction – happiness from using the e-learning system (e-learning platforms, e-games, simulators poses an important research subject matter. In the present paper, it is presented a research on course conducted in the Marine Training Centre of Piraeus. In particular, this research with the use of a neuroscience tools-gaze tracker and voice recording (lexical analysis, investigates the amount of satisfaction of the students using Engine room simulator (ERS 5L90MCL11, Kongsberg 2003 AS and ECDIS system by monitoring the users’ eye movement and speech in combination with the use of qualitative and quantitative methods. The ultimate goal of this research is to find and test the critical factors that influence the educational practice and user satisfaction of e-learning marine systems and the ability to conduct full-time system control by the marine crew.

  17. Tyrihans SRSWI (subsea raw seawater injection)

    Energy Technology Data Exchange (ETDEWEB)

    Time, Nils Petter

    2010-07-01

    By the summer of 2010, Statoil will have installed and commissioned a 2 x 2.5 MW electrical subsea pump system for injection of seawater on the Tyrihans field. Powered from the Kristin platform, the system will pump untreated water directly from the sea into one well at a rate of 14000 m3/day to achieve an Increased Oil Recovery of 10%. The pump system was designed and delivered by Aker Solutions and interfaces the Tyrihans subsea production system delivered by FMC, a power umbilical from Nexans as well as the Kristin topside facilities. In addition to qualification testing, the SRSWI system underwent extensive system testing, including performance- and long term testing, and function testing of the control system from FMC and Kongsberg Maritime. The subsea modules of the SRSWI system and the power umbilical were installed by Acergy's vessel Scandi Acergy, while the topside transformers and variable speed drives were installed on Kristin by Aker Reinertsen, the topside modifications and hook-up contractor. The many interfaces in this project required close and constructive cooperation between the parties in all phases of the development. This paper summarises the experiences from the project. (Author)

  18. 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.

  19. A new multibeam swath mapping echosounder for USCGC Healy

    Science.gov (United States)

    Chayes, D. N.; Roberts, S. D.; Perron, P. J.; Beaudoin, J.; Arko, R. A.; Perry, R. S.

    2010-12-01

    The Healy is the primary U.S. research icebreaker working in the Arctic. In 2003, the UNOLS Arctic Icebreaker Coordinating Committee (AICC) endorsed a plan to replace the aging SeaBeam 2112 multibeam echosounder that was purchased for the Healy at the beginning of construction and delivered with the vessel. Replacement was judged necessary due primarily to age and support issues associated with the original multibeam. Although the original plan was to do the replacement during the regularly scheduled drydock during CY 2006-07, the goal was realized during the CY 2009-10 drydock in Seattle, WA. The selected replacement was a Kongsberg EM122 with one degree (1°) transmit and two degree (2°) beam widths. The transducers are recessed behind windows to protect them from ice damage. The EM122 is configured with water column and raw stave data recording capabilities along with a synchronization interface. Due to the long cable runs and the potential for electromagnetic interference (EMI), a fiberoptic interface was implemented for this system. The installation was completed just prior to departure from the drydock in mid-March 2010, with integration into the existing data system largely completed prior to getting underway for engine trials. A successful Sea Acceptance Test was completed on June 12, 2010, just prior to the first of three research cruises in the Arctic during the 2010 season. Details of the installation and performance of the system will be presented.

  20. Three-dimensional mapping of the sea ice underside from AUVS and applications to the offshore industry

    Energy Technology Data Exchange (ETDEWEB)

    Wadhams, P.; Doble, M.J. [Cambridge Univ., Cambridge, (United Kingdom). Dept. of Applied Mathematics and Theoretical Physics; Wilkinson, J.P. [Scottish Association for Marine Science, Oban (United Kingdom). Dunstaffnage Marine Laboratory

    2008-09-15

    The first multibeam digital terrain mapping of the sea ice underside was performed in August 2004 by the Autosub-2 autonomous underwater vehicle (AUV), operating off northeast Greenland, using a Kongsberg EM2000 sonar. This paper presented some of the high-quality imagery from the experiment, and discussed its implications for ice thickness mapping and other applications. A second mapping experiment took place in April 2007, but this time using a small ice-launched Gavia AUV, equipped with a GeoSwath 500 kHz interferometric sonar system. Gavia could be launched and recovered manually through 3 by 1 metre holes while Autosub required a ship and a crane. The paper also described and contrasted the greater range of Autosub with the greater flexibility of Gavia in multisensor programs. Finally, the paper addressed how AUV techniques could be applied to problems such as mapping rubble fields around drilling platforms, oil containment by sea ice, and other topics of interest to the offshore industry. It was concluded that the combination of an AUV and a multibeam sonar provides a new dimension to under-ice studies, and is important for work on ice thickness changes, the disappearance of deep ridges from the Arctic, navigability in ice, the effects of oil and other pollutants, the interactions between sea ice and under-ice currents and water structure, the underside as biological habitat, and many other studies critical to the role of ice in polar climate change and ice mechanics. 22 refs., 5 figs.

  1. The Arctic DP Research Project: Effective Stationkeeping in Ice

    Directory of Open Access Journals (Sweden)

    Roger Skjetne

    2014-10-01

    Full Text Available Stress on the environment from a potentially growing energy use is set to rise. Without doubt the energy resources in Arctic regions will be developed. An important goal will be to exploit the resources offered by for instance the Barents Sea as a new European energy province, and to do this in accordance with the principles of sustainable development that have successfully been used e.g. in the North Sea. The special edition of MIC on Arctic DP presents a set of articles that summarize to an extent the activities of the research project Arctic DP: Safe and green dynamic positioning operations of offshore vessels in an Arctic environment. This project was awarded in 2010 by the Research Council of Norway (RCN as a competence-building project (KMB project to NTNU and its partners Kongsberg Maritime, DNV GL, and Statoil. The objective was to target some of the challenges related to safe Arctic offshore operations by dynamic positioning. In this first article of the Arctic DP special edition we discuss the background for and establishment of the project, its planning and execution, and project closure. An overview is given for the scientific and engineering research performed in the project, with an account of what we have considered as Effective stationkeeping in ice by dynamic positioning. The corresponding research activities conducted under this main theme is summarized.

  2. Lake Tahoe Bottom Characteristics Extracted from SHOALS Lidar Waveform Data and Compared to Backscatter Data From a Multibeam Echo Sounder

    Science.gov (United States)

    Elston, G. R.; Gardner, J. V.

    2002-12-01

    The waveforms recorded by airborne lidar bathymetry (ALB) systems are currently processed only for depth information. In addition to bathymetry, multibeam echo sounder (MBES) systems provide backscatter data in which regions of different acoustic properties are distinguishable. These regions can often be correlated to different bottom types. Initial attempts to extract equivalent data from the ALB waveforms have confirmed the expectation that such information is encoded in those waveforms. Water clarity, bathymetry, and bottom type control the detailed shapes of ALB waveforms in different ways. Specific features of a bottom-reflected signal can be identified, for example its rise-time and amplitude, and used for clustering and classifying the individual data points. Two data sets from Lake Tahoe are available for comparison: ALB data from the SHOALS (scanning hydrographic operational airborne lidar survey) system of the US Army Corps of Engineers, and Simrad EM1000 MBES data from the USGS. Feature extraction, clustering, and classification of the SHOALS data reveals changes in the optical bottom reflectance characteristics that are echoed in the acoustic bottom backscatter properties.

  3. Epibiotic relationships on Zygochlamys patagonica (Mollusca, Bivalvia, Pectinidae) increase biodiversity in a submarine canyon in Argentina

    Science.gov (United States)

    Schejter, Laura; López Gappa, Juan; Bremec, Claudia Silvia

    2014-06-01

    The continental slope of the southern SW Atlantic Ocean has many distinguishable deep submarine canyons, varying in depth and extension. The benthic fauna within one of them, detected in April 2005 by means of a multibeam SIMRAD EM1002 sonar, and located at 43°35‧S to 59°33‧W, 325 m depth, was studied to discuss faunal affinities with the neighbouring Patagonian scallop fishing grounds located at upper slope depths. In order to add faunal information to the previous general study, we studied the epibiotic species settled on Patagonian scallops (the dominant species in the area) collected in the reference sampling site using a 2.5-m mouth-opening dredge, 10 mm mesh size. We sampled 103 scallops with shell heights between 22 and 69 mm; epibionts were recorded on both valves. We found 53 epibiotic taxa, which were most conspicuous on the upper valve. Bryozoa was the most diverse group (34 species) while Polychaeta was the most abundant group, recorded on 94% of the scallops. Stylasteridae (2 species) and Clavulariidae (Cnidaria) conform newly recorded epibionts on Z. patagonica and the sponge Tedania (Tedaniopsis) infundibuliformis also represents a new record for the SW Atlantic Ocean.

  4. The relationship among oceanography, prey fields, and beaked whale foraging habitat in the Tongue of the Ocean.

    Directory of Open Access Journals (Sweden)

    Elliott L Hazen

    Full Text Available Beaked whales, specifically Blainville's (Mesoplodon densirostris and Cuvier's (Ziphius cavirostris, are known to feed in the Tongue of the Ocean, Bahamas. These whales can be reliably detected and often localized within the Atlantic Undersea Test and Evaluation Center (AUTEC acoustic sensor system. The AUTEC range is a regularly spaced bottom mounted hydrophone array covering >350 nm(2 providing a valuable network to record anthropogenic noise and marine mammal vocalizations. Assessments of the potential risks of noise exposure to beaked whales have historically occurred in the absence of information about the physical and biological environments in which these animals are distributed. In the fall of 2008, we used a downward looking 38 kHz SIMRAD EK60 echosounder to measure prey scattering layers concurrent with fine scale turbulence measurements from an autonomous turbulence profiler. Using an 8 km, 4-leaf clover sampling pattern, we completed a total of 7.5 repeat surveys with concurrently measured physical and biological oceanographic parameters, so as to examine the spatiotemporal scales and relationships among turbulence levels, biological scattering layers, and beaked whale foraging activity. We found a strong correlation among increased prey density and ocean vertical structure relative to increased click densities. Understanding the habitats of these whales and their utilization patterns will improve future models of beaked whale habitat as well as allowing more comprehensive assessments of exposure risk to anthropogenic sound.

  5. Meter Accuracy Seafloor Geodesy using Repeated Multibeam Surveys

    Science.gov (United States)

    DeSanto, J. B.; Sandwell, D. T.

    2014-12-01

    Ship-board multibeam surveys are a useful tool in measuring tectonic deformation of the seafloor, having been used to measure the ~50 m of surface slip along the Japan trench during the 2011 Tohoku-Oki earthquake with an uncertainty of 20 m (Fujiwara et al, 2011, Science). In this study, we investigate the improvement in positioning accuracy obtainable when comparing multibeam and sidescan surveys repeated along the same track to within 1/10 of the critical baseline and taken at a slow ship speed of 1 knot. We compare two surveys of the Juan de Fuca Ridge axis fitting these criteria with two coincident surveys of the Cocos Ridge, taken at 11 knots. Both pairs of surveys were collected using a Simrad EM120 sonar system aboard the RV Roger Revelle. We find the multibeam surveys of the Juan de Fuca ridge axis sufficient to measure displacements accurate to better than 2 m, a marked improvement over the 50 m accuracy of the Cocos ridge surveys. Likewise, we can measure displacement accurate to 2 m using the sidescan data from the Juan de Fuca surveys. This accuracy is sufficient to observe meter-level horizontal movements on the deep ocean associated with large earthquakes and landslides.

  6. 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 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.

  7. Multifrequency analyses of fish distributions in the northwest Atlantic

    Science.gov (United States)

    Jech, J. Michael

    2004-05-01

    Routine acoustical surveys for estimating Atlantic herring (Clupea harengus) population abundance have been conducted on Georges Bank during the autumn spawning season from 1998 to present. Acoustical data are collected with a Simrad EK500 scientific echo sounder operating at 12 or 18, 38, and 120 kHz, and split-beam (the 12-kHz system is a single beam) transducers. Biological measurements and verification of acoustical scatterers are obtained with a pelagic trawl. Acoustical data are evaluated (scrutinized) manually to remove noise, faulty bottom detections, and to classify acoustical backscattering to species. Species classification is currently subjective, and is based on the experience of the scientists and trawl catches. Objective species classification and automated fish density and abundance estimates are an obvious goal for fisheries surveys using advanced technologies. Classification methods using relationships among frequency-dependent volume backscattering strengths, such as presence-absence and combination-permutation, are described and presented. Results indicate that while classification using these methods and acoustical information alone is not robust, these methods highlight backscattering patterns within aggregations and have the potential to characterize backscattering patterns observed in fisheries acoustics data. [Work supported by NOAA Fisheries and ONR.

  8. Predicting the Presence of Large Fish through Benthic Geomorphic Features

    Science.gov (United States)

    Knuth, F.; Sautter, L.; Levine, N. S.; Kracker, L.

    2013-12-01

    Marine Protected Areas are critical in sustaining the resilience of fish populations to commercial fishing operations. Using acoustic data to survey these areas promises efficiency, accuracy, and minimal environmental impact. In July, 2013, the NOAA Ship Pisces collected bathymetric, backscatter and water column data for 10 proposed MPA sites along the U.S. Southeast Atlantic continental shelf. A total of 205 km2 of seafloor were mapped between Mayport, FL and Wilmington, NC, using the SIMRAD ME70 and EK60 echosounder systems. These data were processed in Caris HIPS, QPS FMGT, MATLAB and ArcGIS. The backscatter and bathymetry reveal various benthic geomorphic features, including flat sand, rippled sand, and rugose hard bottom. Water column data directly above highly rugose hardbottom contains the greatest counts for large fish populations. Using spatial statistics, such as a geographically weighted regression model, we aim to identify features of the benthic profile, including rugosity, curvature and slope, that can predict the presence of large fish. The success of this approach will greatly expedite fishery surveys, minimize operational cost and aid in making timely management decisions.

  9. Dissipation processes in the Tongue of the Ocean

    Science.gov (United States)

    Hooper V, James A.; Baringer, Molly O.; St. Laurent, Louis C.; Dewar, William K.; Nowacek, Doug

    2016-05-01

    The Tongue of the Ocean (TOTO) region located within the Bahamas archipelago is a relatively understudied region in terms of both its biological and physical oceanographic characteristics. A prey-field mapping cruise took place in the fall between 15 September 2008 and 1 October 2008, consisting of a series of transects and "clovers" to study the spatial and temporal variability. The region is characterized by a deep scattering layer (DSL), which is preyed on by nekton that serves as the food for beaked whale and other whale species. This study marks the first of its kind where concurrent measurements of acoustic backscatter and turbulence have been conducted for a nekton scattering layer well below the euphotic zone. Turbulence data collected from a Deep Microstructure Profiler are compared to biological and shear data collected by a 38 kHz Simrad EK 60 echo sounder and a hydrographic Doppler sonar system, respectively. From these measurements, the primary processes responsible for the turbulent production in the TOTO region are assessed. The DSL around 500 m and a surface scattering layer (SSL) are investigated for raised ɛ values. Strong correlation between turbulence levels and scattering intensity of prey is generally found in the SSL with dissipation levels as large as ˜10-7 W kg-1, 3 orders of magnitude above background levels. In the DSL and during the diel vertical migration, dissipation levels ˜10-8 W kg-1 were observed.

  10. Dorsal and ventral target strength measurements on gilthead sea bream (Sparus aurata) in sea cages

    CERN Document Server

    Soliveres, Ester; Espinosa, Victor

    2012-01-01

    The aim of this study is to establish a relationship between target strength (TS) and total body length of the gilthead sea bream (Sparus aurata), in order to monitor its growth in sea cages. Five classes of commercial size gilthead sea bream are characterized, comprising lengths from 20 to 25 cm, corresponding to weights between 160 and 270 g. A few specimens were introduced into a sea cage of 3 m in diameter and a height of 2.7 m. We measure TS directly using a Simrad EK60 echosounder with a 7^{\\circ} split-beam transducer working at 200 kHz. The transducer was located in the center of the cage during measurements, at the bottom facing upwards for ventral recordings and on the surface facing downwards to perform dorsal recordings. Two analyses based on single echo detection were performed: the first one obtains compensated transducer directivity TS values from intensity and angular echosounder data; while the second one omit phase information, affording uncompensated TS values (TSu). Two algorithms have bee...

  11. The relationship among oceanography, prey fields, and beaked whale foraging habitat in the Tongue of the Ocean.

    Science.gov (United States)

    Hazen, Elliott L; Nowacek, Douglas P; St Laurent, Louis; Halpin, Patrick N; Moretti, David J

    2011-04-27

    Beaked whales, specifically Blainville's (Mesoplodon densirostris) and Cuvier's (Ziphius cavirostris), are known to feed in the Tongue of the Ocean, Bahamas. These whales can be reliably detected and often localized within the Atlantic Undersea Test and Evaluation Center (AUTEC) acoustic sensor system. The AUTEC range is a regularly spaced bottom mounted hydrophone array covering >350 nm(2) providing a valuable network to record anthropogenic noise and marine mammal vocalizations. Assessments of the potential risks of noise exposure to beaked whales have historically occurred in the absence of information about the physical and biological environments in which these animals are distributed. In the fall of 2008, we used a downward looking 38 kHz SIMRAD EK60 echosounder to measure prey scattering layers concurrent with fine scale turbulence measurements from an autonomous turbulence profiler. Using an 8 km, 4-leaf clover sampling pattern, we completed a total of 7.5 repeat surveys with concurrently measured physical and biological oceanographic parameters, so as to examine the spatiotemporal scales and relationships among turbulence levels, biological scattering layers, and beaked whale foraging activity. We found a strong correlation among increased prey density and ocean vertical structure relative to increased click densities. Understanding the habitats of these whales and their utilization patterns will improve future models of beaked whale habitat as well as allowing more comprehensive assessments of exposure risk to anthropogenic sound.

  12. 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

  13. 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

  14. Impact of Offshore Wind Energy Plants on the Soil Mechanical Behaviour of Sandy Seafloors

    Science.gov (United States)

    Stark, Nina; Lambers-Huesmann, Maria; Zeiler, Manfred; Zoellner, Christian; Kopf, Achim

    2010-05-01

    Over the last decade, wind energy has become an important renewable energy source. Especially, the installation of offshore windfarms offers additional space and higher average wind speeds than the well-established windfarms onshore. Certainly, the construction of offshore wind turbines has an impact on the environment. In the framework of the Research at Alpha VEntus (RAVE) project in the German offshore wind energy farm Alpha Ventus (north of the island Borkum in water depths of about 30 m) a research plan to investigate the environmental impact had been put into place. An ongoing study focuses on the changes in soil mechanics of the seafloor close to the foundations and the development of scour. Here, we present results of the first geotechnical investigations after construction of the plants (ca. 1 - 6 months) compared to geotechnical measurements prior to construction. To study the soil mechanical behaviour of the sand, sediment samples from about thirty different positions were measured in the laboratory to deliver, e.g., grain size (0.063 - 0.3 mm), friction angles (~ 32°), unit weight (~ 19.9 kN/m³) and void ratios (~ 0.81). For acoustic visualisation, side-scan-sonar (towed and stationary) and multibeam-echosounders (hull mounted) were used. Data show a flat, homogenous seafloor prior to windmill erection, and scouring effects at and in the vicinity of the foundations afterwards. Geotechnical in-situ measurements were carried out using a standard dynamic Cone Penetration Testing lance covering the whole windfarm area excluding areas in a radius 50 %) occur above all close to the foundations. Furthermore, patterns of relatively soft zones (qsbc.: 50 - 80 kPa) and hard zones (qsbc. > 100 kPa) were mapped during the high-resolution surveys close to the foundation. Beside that, a very soft sediment layer (0.03 - 0.05 m) drapes most of the soft zones. This may be recently eroded and re-deposited sediment, whereas the hard zones may indicate areas of sediment

  15. 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

  16. Integration of NOAA Ship Okeanos Explorer Seafloor Mapping, Little Hercules ROV, and Sentry AUV Data into Ocean Exploration Operations and Public Data Holdings

    Science.gov (United States)

    Lobecker, E.; Malik, M.; Skarke, A. D.; VerPlanck, N.

    2012-12-01

    Within NOAA's Office of Ocean Exploration and Research, the Okeanos Explorer Program's main tools for preliminary ocean exploration include a Kongsberg EM 302 multibeam sonar (30 kHz), Kongsberg EK 60 singlebeam sonar (18 kHz), and Knudsen subbottom profiler (3.5 kHz chirp). The program devoted multiple expeditions in the Gulf of Mexico and U.S. Atlantic Margin during its 2012 Field Season to confirm and further develop the EM 302 multibeam sonar's water column backscatter data capability to detect gaseous seeps and vents. While mapping in the seafloor and water column in the vicinity of the salt domes of the Northern Gulf of Mexico, the EM 302 detected over two hundred distinct seeps in the water column. Several seeps have been explored in more detail using high definition cameras and lighting systems of the remotely operated vehicle Little Hercules and the camera platform Seirios. This included filming bubbles escaping from the seafloor at the locations determined by the EM 302 data to ground truth EM302 observations and deduce other properties of these gas seeps e.g. gas flux, and effect of these seeps on surrounding ecosystem. These seeps are now a major research focus area by scientists at the University of New Hampshire's Center for Coastal and Ocean Mapping and other academic institutions around the U.S., and the U.S. Bureau of Ocean Energy Management. . While mapping the Blake Ridge and Cape Fear Diapirs, seven distinct seeps were detected, each rising approximately 900 meters from the seafloor in water depths ranging from 2200 to 2500 meters. Several of these seeps were further explored with Woods Hole Oceanographic Institute's Sentry autonomous underwater vehicle, utilizing itsReson 7125 high resolution multibeam, photo imagery, sidescan, subbottom, and various in-situ sensors to characterize the local environment. It is to be noted that very few of these seeps were previously known. Following the Okeanos Explorer Program's paradigm of "Always Exploring

  17. Three-dimensional observations of swarms of Antarctic krill ( Euphausia superba) made using a multi-beam echosounder

    Science.gov (United States)

    Cox, Martin J.; Warren, Joseph D.; Demer, David A.; Cutter, George R.; Brierley, Andrew S.

    2010-04-01

    Antarctic krill ( Euphausia superba) aggregate in dense swarms. Previous investigations of krill swarms have used conventional single- or split-beam echosounders that, with post-processing, provide a two-dimensional (2-D) view of the water column, leaving the third dimension to be inferred. We used a multi-beam echosounder system (SM20, 200 kHz, Kongsberg Mesotech Ltd, Canada) from an inflatable boat (length=5.5 m) to sample water-column backscatter, particularly krill swarms, directly in 2-D and, with post-processing, to provide a three dimensional (3-D) view of entire krill swarms. The study took place over six days (2-8 February 2006) in the vicinity of Livingston Island, South Shetland Islands, Antarctica (62.4°S, 60.7°W). An automatic 3-D aggregation detection algorithm resolved 1006 krill swarms from the survey data. Principal component analyses indicated that swarm morphology metrics such as length, surface area and volume accounted for the largest between swarm variance, followed by echo energy, and finally swarm geographic location. Swarms did not form basic cylindrical or spherical shapes, but had quite consistent surface area to volume ratios of 3.3 m -1. Swarms were spatially segregated, with larger sizes (mean north-south length=276 m, at least double that of two other swarm classifications), found to the northwest of the survey area. The apparent clustering of swarm types suggests that krill biomass surveys and ecosystem investigations may require stratified survey design, in response to varying 3-D swarm morphology, variation that may be driven in turn by environmental characteristics such as bathymetry.

  18. High-resolution Topography of PACMANUS and DESMOS Hydrothermal Fields in the Manus Basin through ROV "FAXIAN"

    Science.gov (United States)

    Luan, Z.; Ma, X.; Yan, J.; Zhang, X.; Zheng, C.; Sun, D.

    2016-12-01

    High-resolution topography can help us deeply understand the seabed and related geological processes (e.g. hydrothermal/cold spring systems) in the deep sea areas. However, such studies are rare in China due to the limit of deep-sea detection technology. Here, we report the advances of the application of ROV in China and the newly measured high-resolution topographical data in PACMANUS and DESMOS hydrothermal fields. In June 2015, the ROV "FAXIAN" with a multibeam system (Kongsberg EM2040) was deployed to measure the topography of PACMANUS and DESMOS hydrothermal fields in the Manus basin. A composite positioning system on the ROV provided long baseline (LBL) navigation and positioning during measurements, giving a high positioning accuracy (better than 0.5m). The raw bathymetric data obtained were processed using CARIS HIPS (version 8.1). Based on the high-resolution data, we can describe the topographical details of the PACMANUS and DESMOS hydrothermal fields. High-resolution terrain clearly shows the detailed characters of the topography in the PACMANUS hydrothermal field, and some cones are corresponding to the pre discovered hydrothermal points and volcanic area. Most hydrothermal points in the PACMANUS hydrothermal field mainly developed on the steep slopes with a gradient exceeding 30 °. In contrast, the DESMOS field is a caldera that is approximately 250 m deep in the center with an E-W diameter of approximately1 km and a N-S diameter of approximately 2 km. The seafloor is much steeper on the inner side of the circular fracture. Two highlands occur in the northern and the southern flanks of the caldera. Video record indicated that pillow lava, sulfide talus, breccia, anhydrite, outcrops, and sediment all appeared in the DESMOS field. This is the first time for the ROV "FAXIAN" to be used in near-bottom topography measurements in the hydrothermal fields, opening a window of deep-sea researches in China.

  19. Estimating dependability of programmable systems using bayesian belief nets

    Energy Technology Data Exchange (ETDEWEB)

    Gran, Bjoern Axel; Dahll, Gustav

    2000-05-15

    The research programme at the Halden Project on software safety assessment is augmented through a joint project with Kongsberg Defence and Aerospace AS and Det Norske Veritas. The objective of this project is to investigate the possibility to combine the Bayesian Belief Net (BBN) methodology with a software safety standard. The report discusses software safety standards in general, with respect to how they can be used to measure software safety. The possibility to transfer the requirements of a software safety standard into a BBN is also investigated. The aim is to utilise the BBN methodology and associated tools, by transferring the software safety measurement into a probabilistic quantity. In this way software can be included in a total probabilistic safety analysis. This project was performed by applying the method for an evaluation of a real, safety related programmable system which was developed according to the avionic standard DO-178B. The test case, the standard, and the BBN methodology are shortly described. This is followed by a description of the construction of the BBN used in this project. This includes the topology of the BBN, the elicitation of probabilities and the making of observations. Based on this a variety of computations are made using the SERENE methodology and the HUGIN tool. Observations and conclusions are made on the basis of the findings from this process. This report should be considered as a progress report in a more long-term activity on the use of BBNs as support for safety assessment of programmable systems. (Author). 23 refs., 9 figs., tabs

  20. Characterisation of Na-metasomatism in the Sveconorwegian Bamble Sector of South Norway

    Directory of Open Access Journals (Sweden)

    Ane K. Engvik

    2014-09-01

    Full Text Available Na-metasomatism in the form of albitisation is regionally extensive in the Precambrian crust of southern Scandinavia and is particularly widespread in the Bamble Sector, the Kongsberg-Modum Sector and the Norwegian part of the Mylonite Zone. Sites of albitisation outside these belts are associated with hydrothermal breccia pipes and fracture-bound alteration. The albitites are composed of near end-member sodic plagioclase (An0–5Ab94–99 with minor carbonate (calcite and dolomite, rutile, clinopyroxene (En30Fs21–23Wo47–49, amphibole (edenite-pargasite, quartz, titanite, tourmaline, epidote (Fe3+ = 0.20–0.85 a.p.f.u and chlorite (Mg# = 0.81–0.89. The albitites have been studied in detail in the region around the town of Kragerø, and are described as albitisation along veins, as breccias, albitic felsites, massive carbonate-bearing albitites and megascale clinopyroxene-titanite-bearing albitite. The strong fluid control on their formation is illustrated by the veining and mineral replacement reactions, showing fluid transport by a H2O-CO2 fluid rich in Na, depleting Fe and Mg from the host rock, in accordance with calculated mass transfer. A study of the mineralogical replacement reactions in combination with a regional compilation has demonstrated the relationship between metasomatic processes and the formation of apatite, rutile and Fe deposits. The albitites occur spatially associated with other metasomatic rocks such as scapolitised metagabbros. We document that metasomatism is an important mineral- and rock-forming process in the continental crust, which in the Bamble Sector is a part of the tectonometamorphic evolution of the Sveconorwegian orogen.

  1. 珠江首次禁渔西江段鱼类资源声学跟踪监测分析%Acoustic monitoring on fish resources in Xijiang section of Pearl River during first closed fishing season

    Institute of Scientific and Technical Information of China (English)

    武智; 谭细畅; 李新辉; 汤勇

    2014-01-01

    2011年珠江开始实行禁渔期制度。该研究采用 Simrad EY60鱼探仪,分别于2010年5月19日和2011年5月22日对珠江西江段进行了走航式探测。结果显示,珠江禁渔期期间西江段鱼类资源密度增加,2010年和2011年鱼类平均密度分别为0.0513尾·m -3和0.1068尾·m -3,根据渔获物调查数据,推算增幅分别为广东鲂(Megalo-brama terminalis)47.85%、赤眼鳟(Squaliobarbus curriculus)18.54%、鲮(Cirrhina moitorella)10.87%和鳊(Parabra-mis pekinensis)6.25%;两年西江段深水区域鱼类密度均较大,尤其是水底结构为凹形区域,鱼类有明显的聚集现象;浅水区域且底部较平整的水域,鱼类分布分散且密度较低;垂直分布方面,鱼类主要分布4~10 m 中下层水层。珠江禁渔期的实施,在一定程度上保护了鱼类的产卵亲体繁殖,对鱼类资源数量的补充起到了增殖作用,同时在很大程度上护养了鱼类的自然生长,起到了资源增重作用。%Closed fishing season was initially implemented in Pearl River in 2011. We used a Simrad EY60 echo-sounder with 120 kHz split-beam transducer to survey the Xijiang section of Pearl River. The results show that during the closed season,the density of fish resources was increasing,and the average fish densities were 0. 051 3 ind·m - 3 and 0. 106 8 ind·m - 3 in 2010 and 2011,respec-tively. According to the data of catches,the increases were deduced as follows:Megalobrama terminalis 47. 85% ,Squaliobarbus cur-riculus 18. 54% ,Cirrhina moitorella 10. 87% and Parabramis pekinensis 6. 25%. The deep water had higher fish density than shallow water,especially that fish obviously aggregated in concave region. The fish mainly distributed at depth of 4 ~ 10 m. The implementa-tion of closed fishing season,to some extent,protects breeding of spawning stocks and supplements fish resources as well as mainte-nances natural growth of fishes.

  2. 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.

  3. Enigmatic sediment ridges in the German Bight - glacial vs post-glacial morphologies?

    Science.gov (United States)

    Unnithan, Vikram; Pio Rossi, Angelo; Praeg, Daniel

    2014-05-01

    The German Wadden Sea extends over 1000 km from the Dutch coast to that of Sweden and consists of a long chain of barrier islands and ephemeral sand banks punctuated by estuaries and rivers. The sedimentary environment is currently shaped and characterised by storm surges, high tidal and wave energy levels. However, this part of the North Sea has been repeatedly covered by continental ice sheets, and it remains unclear how glacial to interglacial sedimentary processes may have influenced seabed morphology in the region. The study area is situated approximately 70 km north of Cuxhaven, and 5 km due east of the islands of Helgoland and Dune. It covers an approximate area of 5 km square with water depths ranging from 50 m in the south to about 20 m in the north. High resolution multibeam (Simrad EM710) and parametric echosounder (Innomar SES2000) data were acquired during graduate and undergraduate teaching excursions on the RV Heincke in Spring 2010 (HE-324) and 2011 (HE-349). The seabed swath bathymetric data reveal distinctive linear seabed ridges. The ridges trend NNW-SSE, are 1-5 m in height, have wavelengths on the order of 100 m and crest lengths ranging from 100-2500 m. The ridge crests are broadly anastomosing. They bifurcate towards the north to form more subdued structures, while they converge and disappear to the south. Profiles across the ridges show an asymmetric structure, with steeper slopes trending west in the western part of the study area but trending east in the eastern part. These enigmatic sedimentary structures have not been previously mapped in the Wadden Sea, and their origin remains uncertain. Possible interpretations to be tested include sub-crop structural control on seabed morphology, relict glacial or glaciofluvial landforms and post-glacial marine bedforms linked to processes of sediment redistribution.

  4. 基于水声学探测的香溪河鱼类资源时空分布特征评估%HYDROACOUSTIC ASSESSMENT OF SPATIO-TEMPORAL DISTRIBUTION AND ABUNDANCE OF FISH RESOURCES IN THE XIANGXI RIVER

    Institute of Scientific and Technical Information of China (English)

    连玉喜; 黄耿; Ma(l)gorzata Godlewska; 李翀; 赵修江; 叶少文; 李钟杰

    2015-01-01

    为了掌握三峡水库香溪河鱼类资源时空分布特征,2013年5月和11月运用Simrad EY60型分裂波束回声探测仪在香溪河进行了水声学探测,辅以常规渔获物分析方法.渔获物调查共发现鱼类7科41种,其中似鳊、贝氏餐、餐、银(约)和蛇(约)等小型鱼类在数量上占据优势地位.水声学探测结果表明,香溪河春季鱼类密度显著高于秋季,采用加权平均法求得2013年5月和11月探测的鱼类密度分别为53.4和15.4 ind./1000 m3.鱼类资源在空间上不均匀分布,从高岚河至香溪河口鱼类密度逐渐降低;在垂直方向上,春季和秋季水声学探测的鱼类密度显示出相同的趋势,即表层>中层>底层.在运用鱼类生物操纵改善水质途径方面,建议通过壮大肉食性鱼类种群来控制小型鱼类资源量,同时通过增殖放流鲢、鳙以加强对浮游植物的滤食作用.

  5. 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.

  6. Quantifying submarine landslide processes driven by active tectonic forcing: Cook Strait submarine canyon, New Zealand.

    Science.gov (United States)

    Mountjoy, J. J.; Barnes, P. M.; Pettinga, J. R.

    2006-12-01

    The Cook Strait submarine canyon system is a multi-branched, deeply incised and highly sinuous feature of New Zealand's active margin, covering some 1500km2 of sea floor between the North and South Islands and spanning water depths of between 50 and 2700m. The canyon occurs at the transition from the westward dipping oblique subduction zone adjacent to the SE North Island and the zone of continental transpression in NE South Island. The recent acquisition of high resolution (5-10m) SIMRAD EM300 bathymetric data allows active tectonic and geomorphic processes to be assessed and quantified at a level of detail previously not possible. While multiple active submarine fault traces have been identified in the Cook Strait by previous studies, quantitative information on their activity has been limited. Cook Strait is structurally characterized by westward dipping thrust faults and E-W trending dextral strike slip faults. The multiple large magnitude high frequency earthquake sources define zones of very high ground shaking expected to contribute to triggering of extensive submarine slope failures. Landslide activity within the canyon system is widespread and represents the dominant mass movement process affecting canyon heads and walls, redistributing material into valley fills. Complexes of large (km3) multi-stepped, deep-seated (100m) translational bedding plane failures represented by gently sloping (<3°) evacuated slide-scar areas with associated blocky valley fill deposits are numerous. Steep catchment heads, channel walls and the leading edges of asymmetric thrust-fault driven anticlines are dominated by gulley and rill systems with associated eroded and/or incipient slump features. Large (107m3+) slide blocks are recognized in discrete failures with quantifiable displacement vectors. Tsunamigenic landslides in this environment are inevitable. This study will provide quantification of landslide models including triggering mechanisms, discrete geometries and

  7. Comparison of Airborne Lidar and Mulitbeam Bathymetric Data in the Florida Reef Tract Along Broward County

    Science.gov (United States)

    Morton, N. E.; Burd, J. J.; McIntyre, M. L.; O'Kiefe, K. M.; Wheaton, J. L.; Naar, D. F.; Donahue, B. T.; Kohler, M. F.

    2002-12-01

    Most mapping of Florida's coral resources has been in the relatively shallow waters of the Florida Keys. However, it is well known that large concentrations of corals are found in deeper waters off Florida's eastern seaboard. To date, technological limitations have precluded the mapping of corals in these deeper waters. Satellite imaging systems and natural color aerial photography, two mapping mainstays, are generally only effective in Florida waters shallower than 20 meters. Conservation of the northern portion of the Florida reef tract, which parallels the Atlantic coast in Miami-Dade, Broward and Palm Beach counties, has been hampered by the fact that there are little or no coordinated management, monitoring and mapping activities in place. To assist the Broward county shore protection project geographic information systems database, a Laser Airborne Depth Sounder (LADS) survey was performed in 2001. The surveyFlanked the 43 km shoreline to a depth of ~50m and distances out to 2km in the north and 3.5km in the southern portion at a spatial resolution of 1.524m (5ft). Additionally, in November 2000 as part of a container vessel grounding lawsuit, funding was allocated to find an alternative anchorage for Port Everglades. The Simrad EM3000 multibeam system was used to collect data in a 2km x 2km square south of Port Everglades, offshore at a depth from 7m to 36m deep and at a spatial resolution of 1m. The area of overlap coincided with the second and third reef tracts, which have the highest biodiversity of the three reef tracts. These datasets were compared at overlapping geographic extents.

  8. Heard Island and McDonald Islands Acoustic Plumes: Split-beam Echo sounder and Deep Tow Camera Observations of Gas Seeps on the Central Kerguelen Plateau

    Science.gov (United States)

    Watson, S. J.; Spain, E. A.; Coffin, M. F.; Whittaker, J. M.; Fox, J. M.; Bowie, A. R.

    2016-12-01

    Heard and McDonald islands (HIMI) are two active volcanic edifices on the Central Kerguelen Plateau. Scientists aboard the Heard Earth-Ocean-Biosphere Interactions voyage in early 2016 explored how this volcanic activity manifests itself near HIMI. Using Simrad EK60 split-beam echo sounder and deep tow camera data from RV Investigator, we recorded the distribution of seafloor emissions, providing the first direct evidence of seabed discharge around HIMI, mapping >244 acoustic plume signals. Northeast of Heard, three distinct plume clusters are associated with bubbles (towed camera) and the largest directly overlies a sub-seafloor opaque zone (sub-bottom profiler) with >140 zones observed within 6.5 km. Large temperature anomalies did not characterize any of the acoustic plumes where temperature data were recorded. We therefore suggest that these plumes are cold methane seeps. Acoustic properties - mean volume backscattering and target strength - and morphology - height, width, depth to surface - of plumes around McDonald resembled those northeast of Heard, also suggesting gas bubbles. We observed no bubbles on extremely limited towed camera data around McDonald; however, visibility was poor. The acoustic response of the plumes at different frequencies (120 kHz vs. 18 kHz), a technique used to classify water column scatterers, differed between HIMI, suggestiing dissimilar target size (bubble radii) distributions. Environmental context and temporal characteristics of the plumes differed between HIMI. Heard plumes were concentrated on flat, sediment rich plains, whereas around McDonald plumes emanated from sea knolls and mounds with hard volcanic seafloor. The Heard plumes were consistent temporally, while the McDonald plumes varied temporally possibly related to tides or subsurface processes. Our data and analyses suggest that HIMI acoustic plumes were likely caused by gas bubbles; however, the bubbles may originate from two or more distinct processes.

  9. Bathymetry and seafloor image surveys for benthic habitat mapping of Dokdo

    Science.gov (United States)

    Kim, Chang Hwan; Rho, Hyun Soo; Lee, Myung Hoon

    2014-05-01

    Dokdo (do means a island), our study area, is a volcanic island, which is located in the northeastern part of the Ulleung Back-Arc Basin, the East Sea and approximately 216.8 km away from the eastern part of the Korean peninsula. The Dokdo volcano anomalously emerges, rising abruptly from the sea floor (~2,100 m below sea level). Dokdo comprises two main islets (Seo-do and Dong-do) and the associated submerged volcanic edifice. To management the eco-system of coastal area and establish the policy against the change of marine environment, advanced nations for marine have conducted benthic habitat mapping studies like PIBHMC (Pacific Islands Benthic Habitat Mapping Center) and MESH (Mapping European Seabed Habitats) projects. For the benthic habitat mapping of the southern coastal area of Seo-do, the precise topographical map of the coastal area was made using the detailed bathymetry data from multi-beam echosounder (EM 3001, Kongsberg). The seafloor images of the survey area were obtained by Side Scan Sonar (4125, Edgetech). The grain size and TOC (Total Organic Carbon) of 6 surface sediment samples of the survey area were analyzed. We used small research vessels for this study, because of shallow water. The bathymetry data of the survey area show that the range of water depth is about from 1 m to 28 m and the underwater reefs are irregularly scattered and extended from inland of Seo-do, with shallow water depth (within about 10 m). In the underwater reefs area, the flank slopes are very steep and irregular, overlain by many large or small submerged rocks, indicating partial erosion due to waves, strong currents and weathering. And below ~15 m, the bathymetry gradually transitions to a relatively even undulation with a smooth slope. The seafloor images, from Side Scan Sonar, show that many large or small submerged rocks occur in the shallow water and other seabed area is covered with small gravels. The grain size of sediments is varied along bathymetric gradients

  10. 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

  11. What a Difference a Swath Makes!

    Science.gov (United States)

    Mayer, L. A.; Gardner, J. V.

    2014-12-01

    Since the introduction to the academic community of multibeam sonar swath mapping techniques in the late 1970s, the ability to collect high-resolution bathymetry and seafloor imagery has steadily increased. Early systems provided a limited number (e.g., 16) of relatively broad (2-4 degree) beams and swath widths of approximately one times the water depth, whereas current systems offer hundreds of narrower (0.5 to 1 degree) beams over swath widths of five to seven times water depth. Innovations like chirped pulses and high-density beam forming (multiple depth solutions per beam footprint) have also pushed the resolution of modern systems. Despite these improvements, the resolution achievable is fundamentally limited by trade-offs between beam width, bandwidth, transducer size and propagation, resulting in the need for short ranges to the seafloor to achieve the highest levels of resolution. In the deep sea this means delivery of high-frequency, high-resolution mapping systems close to the bottom by means of towed or autonomous vehicles, the trade-off here being limited areal coverage due to narrow swaths and slow mapping speeds. Despite these constraints, we cannot forget that only a small fraction of the deep ocean has been mapped by any sort of swath mapping system (10-20%) and that even a single well-calibrated and properly operated multibeam swath collected at high-speed during a long transit can offer a remarkable amount of insight into seafloor processes. We will illustrate this through the exploration of a single transit by the R/V KILO MOANA (using a Kongsberg EM120 MBES) from Hawaii to Kodiak Alaska. When compared to the best available global bathymetric compilations using both satellite derived bathymetry and existing bathymetric data (e.g., Global Topography of Smith and Sandwell, GMRT, or ETOPO-1), the single swath offers detailed views of deep-sea channels, seamount and guyots, tectonic structure and volcanic processes that are totally absent in the

  12. Mapping cold seeps with high-resolution deep water multibeam echosounders in the Black Sea

    Science.gov (United States)

    Wintersteller, P.; dos Santos Ferreira, C.; Klaucke, I.; Ivanov, M.; Sahling, H.; Bohrmann, G.

    2011-12-01

    Cold seeps are locations at the seafloor where gas and/or fluids are emitting. In contrast to mud volcanoes, which distinctly change the seafloor morphology, cold seeps often lack significant relief. However, in comparison with surrounding sediments seep locations on the sea floor are often characterized by high acoustic backscatter intensity. This was documented during several investigations with deep towed side-scan sonar (SSS) systems in recent years. Authigenic carbonates, free gas and gas hydrates, as evidenced by ground truthing, are responsible for the high backscatter values. Last year's upgrade of the 1°x2° KONGSBERG deep water echosounder EM120 to EM122 on RV Meteor enhanced the system to almost 4 times the previous resolution due to multi-ping and high density signal processing. Based on the physics of sound propagation in the water column, multibeam echosounders (MBES) for deep water use relatively low frequencies of about 12-15 kHz. Apparently highly water-saturated sediments are penetrated by these signals and can cause artificial offsets in bottom detection in comparison to high-frequency echosounders. Nevertheless the effect of the slightly penetrating signal has a useful side effect on the backscatter. Investigations on several seep sites in the Black Sea, carried out with both EM122 and EM710 during Meteror cruise M84-2, resulted in maps of remarkable bathymetric resolution but also showed multibeam backscatter information of a 12 kHz signal to be an excellent tool to map seep-influenced seafloor areas. New seep locations have been mapped in regions of the western Turkish continental margin close to Eregli and of the eastern Turkish margin off Samsun. In both areas high backscatter patches were mapped with nearly comparable resolution as achieved by deep-tow SSS systems. At Eregli the new data is compared with data from a deep-towed EdgeTech SSS system recorded with a frequency of 75 kHz. At Samsun the results are compared with data from a MAK-1

  13. High-resolution Mapping of Offshore and Onshore Glaciogenic Features in Melville Bay, Northwestern Greenland

    Science.gov (United States)

    Freire, F.; Gyllencreutz, R.; Greenwood, S.; Mayer, L. A.; Jakobsson, M.

    2014-12-01

    This study presents results from high resolution mapping in the northwestern part of Greenland's continental shelf, offshore from the Greenland Ice Sheet. The study area is located at about 74o30'N and 58 o40'W where high-resolution seafloor imagery were collected from ~200-500 m water depth. These data were analyzed and compared to existing high-resolution satellite imagery of exposed glacial landforms from the nearby coastal areas. Offshore geophysical mapping equipment consisted of a Kongsberg EM2040 multibeam that was bow-mounted on the sailing vessel Explorer of Sweden together with a Seatex MRU5+ motion sensor and GPS antennas. In addition, a GAVIA autonomous underwater vehicle (AUV) from University of Iceland with installed Geoswath interfometric sonar and Marine Sonic side-scan was used. The data from these systems permitted the production of both 5-m (for the EM2040) and 2-m (for the Geoswath) resolution bathymetric grids for landform analyzes. Sediment characterization analysis was also undertaken using the co-registered backscatter data. The exposed onshore landforms were studied using data from the high-res QuickBird satellite images with a 2-m pixel resolution. Geomorphic analysis of the data shows that past tectonic and glacial scouring processes have shaped the present-day landscape in both the offshore and onshore study areas. The terrain consists of glacially eroded bedrock covered with very thin surficial sediments resembling a 'cnoc-and-lochan' terrain, although the degree of erosion varies spatially, probably as a result of local variations in the rock properties. Different glacially influenced features are identified and described in the study. These features have been used to understand and infer past ice-sheet processes, particularly ice-flow direction and the extent of ice-cover on the continental shelves from previous extreme glaciation events. The backscatter information from the high-resolution interferometric sonar show fine

  14. 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

  15. Comparison of Shallow Survey 2012 Multibeam Datasets

    Science.gov (United States)

    Ramirez, T. M.

    2012-12-01

    The purpose of the Shallow Survey common dataset is a comparison of the different technologies utilized for data acquisition in the shallow survey marine environment. The common dataset consists of a series of surveys conducted over a common area of seabed using a variety of systems. It provides equipment manufacturers the opportunity to showcase their latest systems while giving hydrographic researchers and scientists a chance to test their latest algorithms on the dataset so that rigorous comparisons can be made. Five companies collected data for the Common Dataset in the Wellington Harbor area in New Zealand between May 2010 and May 2011; including Kongsberg, Reson, R2Sonic, GeoAcoustics, and Applied Acoustics. The Wellington harbor and surrounding coastal area was selected since it has a number of well-defined features, including the HMNZS South Seas and HMNZS Wellington wrecks, an armored seawall constructed of Tetrapods and Akmons, aquifers, wharves and marinas. The seabed inside the harbor basin is largely fine-grained sediment, with gravel and reefs around the coast. The area outside the harbor on the southern coast is an active environment, with moving sand and exposed reefs. A marine reserve is also in this area. For consistency between datasets, the coastal research vessel R/V Ikatere and crew were used for all surveys conducted for the common dataset. Using Triton's Perspective processing software multibeam datasets collected for the Shallow Survey were processed for detail analysis. Datasets from each sonar manufacturer were processed using the CUBE algorithm developed by the Center for Coastal and Ocean Mapping/Joint Hydrographic Center (CCOM/JHC). Each dataset was gridded at 0.5 and 1.0 meter resolutions for cross comparison and compliance with International Hydrographic Organization (IHO) requirements. Detailed comparisons were made of equipment specifications (transmit frequency, number of beams, beam width), data density, total uncertainty, and

  16. Mid-water Software Tools and the Application to Processing and Analysis of the Latest Generation Multibeam Sonars

    Science.gov (United States)

    Gee, L.; Doucet, M.

    2010-12-01

    of the significant volume of water column data. Currently, the source conversion system supports a wide variety of hydrographic and fisheries sonars such as the Kongsberg EM3002, EM302, EM122, ME70, EK60, EK500 and Reson 7125. It is proposed that the GWC format be public, and it has been distributed for review and comment to researchers, sonar manufacturers and software developers (http://www.ivs3d.com/support/gwc/). 3-D view of the bubble plume NW Rota Volcano. Data courtesy US Naval Oceanographic Office

  17. 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

  18. GEMAS: Concentrations and origin of indium in agricultural soil of Europe

    Science.gov (United States)

    Ladenberger, Anna; Sadeghi, Martiya; Demetriades, Alecos; Reimann, Clemens; Birke, Manfred; Andersson, Madelen; Jonsson, Erik

    2014-05-01

    Indium is classified as a critical metal, urgently needed in the electronics industry, especially for the production of solar panels and LCD screens. It is a volatile chalcophile rare element and its primary sources are different types of sulphide ore deposits. Although sphalerite is the main host mineral for indium, chalcopyrite-rich ores usually contain the highest contents of this element. Apart from common sulphides, higher indium concentrations can occur in cassiterite, wolframite and magnetite, in addition to few known indium minerals such as roquesite. Indium is a very rare element and its determination needs a technique with very low detection limits. Data for In are hardly ever provided in geochemical data sets due to its function as an internal standard when using the ICP-MS for analysis. Within the GEMAS project, over 4000 samples of agricultural (Ap) and grazing land (Gr) soil have been collected, and indium concentrations have been measured by ICP-MS in an aqua regia extraction. The median value of aqua regia extractable In in European soil is 0.0176 mg/kg in the Ap and 0.0177 mg/kg in the Gr samples. The most striking pattern on an In distribution map of Europe in an aqua regia extraction is the large difference between northern (low - median 0.012 mg/kg In in the Ap samples) and southern Europe (high - median 0.021 mg/kg In in the Ap samples). The boundary between predominantly high and low concentrations follows exactly the southernmost limit of the last glaciation. In southern Scandinavia, clay-rich soil is indicated by In anomalies, as is the Oslo Rift and the old silver mine at Kongsberg (Norway). Generally, distinct In anomalies mark many of the famous old mining areas of the continent, typically those featuring relatively young hydrothermal deposits (northern Portugal, Iberian Pyrite Belt, Cornwall in the UK, Harz in Germany and Erzgebirge at the German/Czech border), and granitic intrusions (probably related to associated Sn and skarn

  19. 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

  20. Submarine canyon morphologies and evolution on a modern carbonate system: the Northern Slope of Little Bahama Bank (Bahamas).

    Science.gov (United States)

    Tournadour, Elsa; Mulder, Thierry; Borgomano, Jean; Hanquiez, Vincent; Ducassou, Emmanuelle; Gillet, Hervé; Sorriaux, Patrick

    2013-04-01

    The recent CARAMBAR cruise (Nov. 2010) on the northern slope of Little Bahama Bank (LBB, Bahamas) provided new seafloor and subsurface data, that improve our knowledge on carbonate slope systems. The new high-resolution multibeam bathymetry data (Kongsberg EM302 echosounder) and very high resolution (3.5 kHz/Chirp subbotom profiler) seismic data show that the upper LBB slope is dissected by 18 canyons. These canyons evolve sharply into short channels opening to depositional fan-shaped lobes. These architectural elements form a narrow carbonate gravity system extending over 40 km along the LBB slope. The features previously described as small linear canyons have a more complex morphology than originally supposed. The several architectural elements that can be distinguished share similar characteristics with siliciclastic canyons. The average morphological features of the canyons are: minimum and maximum water depths of 460 and 970 m resp., mean length = 16.3 km and sinuosity = 1.14. Canyons are floored with flat elongated morphologies interpreted as terraces. Some of these terraces are located at the toe of slide scars on canyon heads and canyon sides which suggest that they result from sediment failures. On the Chirp seismic data, wedge-shape aggrading terraces interpreted as "internal levees" can be observed. These terraces would then be formed by overbanking of the upper part of turbidity currents. Between 530 and 630 m water depth, some canyons exhibit an amphitheater-shaped head with a head wall height ranging from 80 to 100 m. The wall edges of these canyon heads consist of coalescing arcuate slump scars, which suggests that the canyons formed by retrogressive erosion. Other canyons show an amphitheater-shaped head that evolves upslope into linear valleys incising the upper slope between 460 m and 530 m water depth. The onset and the spatial distribution of these linear valleys seem to be influenced by sediments transported from oolitic shoals of Walker Cay

  1. 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

  2. 珠江首次禁渔西江段鱼类资源声学跟踪监测分析

    Institute of Scientific and Technical Information of China (English)

    武智; 谭细畅; 李新辉; 汤勇

    2014-01-01

    2011年珠江开始实行禁渔期制度。该研究采用 Simrad EY60鱼探仪,分别于2010年5月19日和2011年5月22日对珠江西江段进行了走航式探测。结果显示,珠江禁渔期期间西江段鱼类资源密度增加,2010年和2011年鱼类平均密度分别为0.0513尾·m -3和0.1068尾·m -3,根据渔获物调查数据,推算增幅分别为广东鲂(Megalo-brama terminalis)47.85%、赤眼鳟(Squaliobarbus curriculus)18.54%、鲮(Cirrhina moitorella)10.87%和鳊(Parabra-mis pekinensis)6.25%;两年西江段深水区域鱼类密度均较大,尤其是水底结构为凹形区域,鱼类有明显的聚集现象;浅水区域且底部较平整的水域,鱼类分布分散且密度较低;垂直分布方面,鱼类主要分布4--10 m 中下层水层。珠江禁渔期的实施,在一定程度上保护了鱼类的产卵亲体繁殖,对鱼类资源数量的补充起到了增殖作用,同时在很大程度上护养了鱼类的自然生长,起到了资源增重作用。

  3. Creation and Deformation of Hydrous Lithosphere at the Southern Mariana Margin

    Science.gov (United States)

    Martinez, F.; Kelley, K. A.; Stern, R. J.

    2012-04-01

    Mantle lithosphere formed at mid-ocean seafloor spreading centers is thought to be essentially anhydrous because water is strongly partitioned into melt and removed from the mantle during crustal formation. Since water weakens olivine this dehydration process is also thought to strengthen oceanic mantle lithosphere above solidus depths, perhaps helping to focus deformation and melt delivery to the narrow plate boundary zones observed at mid-ocean ridges. In contrast, convergent margins are sites of high water flux from subducting slabs and thereby provide an opportunity to study the creation and deformation of lithosphere in a hydrous environment. The southern Mariana margin presents a rare case in which the upper plate is undergoing active extension parallel to the trench and directly above the subducting slab. The extension has rifted preexisting Paleogene lithosphere resulting in the present-day creation of new lithosphere in this hydrous environment. Here we present preliminary results from R/V Thomas G. Thompson cruise TN273 in December 2011-January 2012 utilizing the Hawaii Mapping Research Group's IMI-30, a 30 kHz deep-towed side-scan sonar, and ship-based Simrad EM302 multibeam bathymetry. The sidescan sonar imagery and multibeam bathymetry map the tectonic and volcanic structure of a 32 x 80 km area referred to as the southeast Mariana forearc rifts (SEMFR), which extend from near the backarc spreading center toward the trench. The sonar imagery shows a complex volcanic and tectonic structure with no single spreading or rifting axis. Volcanism appears to be widely dispersed and separated by faulted areas. Bathymetry data show several rifts spanning this area but no single rift appears to be focusing tectonic activity as earthquake seismicity is broadly distributed across this region. The data depict a broad volcano-tectonic zone of complex deformation and distributed volcanism unlike the narrow plate boundary zones of mid-ocean ridges. This distributed

  4. The influence of cuttlebone on the target strength of live golden cuttlefish (Sepia esculenta at 70 and 120 kHz

    Directory of Open Access Journals (Sweden)

    Daejae Lee

    2016-04-01

    Full Text Available Abstract To quantitatively estimate the influence of cuttlebone on the target strength (TS of golden cuttlefish, the cuttlebone was carefully extracted from 19 live cuttlefish caught using traps in the inshore waters around Geojedo, Korea, in early May 2010 and the TS was measured using split-beam echosounders (Simrad ES60 and EY500. The TS-length relationships for the cuttlefish (before the extraction of cuttlebone, Fish Aquat Sci. 17:361–7, 2014 and the corresponding cuttlebone were compared. The cuttlebone length (L b ranged from 151 to 195 mm (mean L b  = 168.3 mm and the mass (W b ranged from 29.3 to 53.2 g (mean W b  = 38.8 g. The mean TS values at 70 and 120 kHz were −33.60 dB (std = 1.12 dB and −32.24 dB (std = 1.87 dB, respectively. The mean TS values of cuttlebone were 0.19 dB and 0.04 dB lower than those of cuttlefish at 70 and 120 kHz, respectively. For 70 and 120 kHz combined, the mean TS value of cuttlebone was −32.87 dB, 0.11 dB lower than that of cuttlefish (−32.76 dB. On the other hand, the mean TS value of cuttlebone predicted by the regression (TS b  = 24.86 log10 L b – 4.86 log10 λ – 22.58, r 2 = 0.85, N = 38, P < 0.01 was −33.10 dB, 0.04 dB lower than that of cuttlefish predicted by the regression (TS c  = 24.62 log10 L c – 4.62 log10 λ – 22.64, r 2 = 0.85, N = 38, P < 0.01. That is, the contribution of cuttlebone to the cuttlefish TS determined by the measured results was slightly greater than that by the predicted results. These results suggest that cuttlebone is responsible for the TS of cuttlefish, and the contribution is estimated to be at least 99 % of the total echo strength.

  5. Seafloor Mapping of the Southeast Iberian Continental Slope and Western Algero-Balearic Abyssal Plain

    Science.gov (United States)

    Lastras, G.; Canals, M.; León, C.; Elvira, E.; Pascual, L.; Muñoz, A.; de Cárdenas, E.; Acosta, J.

    2014-12-01

    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 2,600 m. Data 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), aiming at creating maps of the fishing grounds of the Mediterranean continental margins of Spain. The edition of the maps has been 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. Multibeam bathymetry data from the continental shelf obtained within the ESPACE project, also in a cooperative frame between IEO and SGP, completes the whole picture from the coastline to the deep abyssal plain. 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 a large number of submarine canyons and gullies, including Palos, Tiñoso, Cartagena Este, Cartagena Oeste, Águilas, Almanzora, Alias, Garrucha and Gata submarine canyons, the Mazarrón, Palomares and Al-Mansour escarpments of probable tectonic origin, the Abubácer, Maimonides and Yusuf ridges, the

  6. 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

  7. Mapping the True 3D Morphology of Deep-Sea Canyons

    Science.gov (United States)

    Huvenne, V. A.; Masson, D.; Tyler, P. A.; Huehnerbach, V.

    2010-12-01

    The importance of submarine canyons as ecosystem hotspots and sediment transport pathways has been recognised for decades (e.g. Heezen et al., 1955; Vetter & Dayton, 1998). However, studying canyon systems in detail is a challenge, because of the complexity and steepness of the terrain. Acoustic surveys are hampered by side-echoes, while the high slope angles cause most types of sampling equipment, deployed from surface vessels, to fail. Ship-borne bathymetric surveys tend to represent the canyon topography in an overly smoothed way as a result of their limited resolution in deep water compared to the scale of the terrain variability. Moreover, it is clear that overhanging cliffs cannot be mapped correctly with traditional, downward looking multibeam echosounders. The increasing availability of underwater vehicles, however, opens new opportunities. During summer 2009, we mapped several submarine canyon habitats in detail, using the UK deep-water Remotely Operated Vehicle (ROV) ISIS. In particular, we developed a new methodology to map vertical cliffs and overhangs by placing the high-resolution Simrad SM2000 multibeam system of the ROV in a forward-looking position rather than in the traditional downward-looking configuration. The cliff morphology was then mapped by moving the ROV laterally in parallel passes at different depths. Repeating this approach at different distances from the cliff face, we obtained maps of varying resolution and extent. The low resolution maps provide an overview of the general geological framework, while individual strata and faunal colonies can be recognised on the highest resolution maps. Using point-cloud models, we combined the ship-borne bathymetry with the ROV-based data, in order to obtain a true 3D seabed morphology of the canyon study site, which can be used for fly-throughs, geomorphological analysis or habitat mapping. With this approach, we could visualise the spatial structure and density distribution of a unique and

  8. 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

  9. Multibeam Mapping of Cretaceous-Paleogene Meteorite Impact Deposits on the Campeche Escarpment, YUCATÁN , MÉXICO

    Science.gov (United States)

    Gwiazda, R.; Paull, C. K.; Caress, D. W.; Rebolledo-Vieyra, M.; Fucugauchi, J. U.; Canales, I.; Sumner, E. J.; Tubau Carbonell, X.; Lundsten, E. M.; Anderson, K.

    2013-12-01

    The Chicxulub crater in the Yucatán Peninsula, México, at the Cretaceous-Paleogene (K-Pg) boundary, is believed to have been created by the impact of a meteorite ~65 million years ago. Ejecta from the impact were deposited beyond the crater site and are now buried under >1 km of Cenozoic carbonate sediments. Outcrops of the ejecta are believed to be exposed on the Campeche escarpment, which is the dramatically steep northern edge of the Yucatán Peninsula. A seafloor-mapping cruise aboard the R/V Falkor, equipped with Kongsberg EM302 30 kHz and EM710 70-100 kHz multibeam sonars, was conducted in March 2013 to produce a detailed map of the escarpment. Surveys were conducted along the escarpment face for 612 km, targeting the water depth range between 400 m and the escarpment base at ≤ 3,700 m. Segments with two distinctive reliefs are observed in the escarpment face: The first type of relief is a continuous slope over the entire surveyed depth, with numerous v-shaped gullies and intervening ridges. In contrast, the second type of relief is characterized by slopes of 5° above ~2-2.5 km depth with an abrupt change to 25° slopes below. As many as 80 submarine canyons are present along this relief. The canyons are topped with semicircular amphitheaters of gentler slopes above ~2-2.5 km but rimmed with 500 m high cliffs on the steep slope section below. The steep cliffs appear free from sediment drape and can be traced laterally for large segments of the escarpment, suggesting that these are horizontal units with outcropping strata. The location of the K-Pg boundary on the escarpment can be inferred from its identification on DSDP Leg 17 Site 86, drilled on a terrace at 1,462 m depth, and 200 m from the edge of the escarpment, and on DSDP Leg 17 Site 94, drilled in 1,793 m depth, 5.5 km from the edge of the platform. Based on the biostratigraphy of core cuttings recovered from both boreholes the base of the Tertiary in Site 86 is placed at between 2,016 and 2,081 m

  10. High temperature antenna pointing mechanism for BepiColombo mission

    Science.gov (United States)

    Mürer, Johan A.; Harper, Richard; Anderson, Mike

    2005-07-01

    This paper describes the two axis Antenna Pointing Mechanism (APM) with dual frequency (X-Ka bands) Rotary Joint (RJ) developed by Kongsberg Defence and Aerospace and BAE Systems, in the frame of the ESA BepiColombo mission to the planet Mercury. The extreme environmental conditions induced by Mercury's proximity to the Sun (up to 14.500 W/m2 direct solar fluxes, up to 5000 W/m2 infrared flux and up to 1200 W/m2 albedo shine form the planet surface), have dictated the need for a specific high temperature development of the pointing mechanism and of its integrated RF Rotary Joint. Global thermal analysis of the antenna predicts qualification temperature for the elevation stage APM between 250°C and 295°C. In addition, the mechanism shall survive extreme cold temperatures during the interplanetary cruise phase. Beside the harsh environment, the stringent pointing accuracy required by the antenna high frequency operations, and the extreme dimensional stability demanded by a radio science experiment (which is using the antenna for range and range rate measurements), have introduced additional, specific challenges to the mechanism design. Innovative solutions have been deemed necessary at system architecture level, in the design of the mechanisms critical areas and in the selection of high temperature compatible materials and processes. The very high working temperature of the mechanism ruled out use of aluminium alloys, which is replaced by Titanium alloy and stainless steels. Special heat treatments of the steel are applied for minimum loss of hardness. The structures are optimised for minimum mass. To handle thermal stresses and distortion, a very compact design of the APM was performed integrating the bearings, position sensor and drive chain within minimum structural length. The Rotary Joint is a unique design tailored to the APM using a common main bearing support. Special manufacturing processes have been tested and applied for manufacture of the very compact

  11. Uppermost Pleistocene drowned coralgal bank detailed bathymetry along the South Texas shelf edge: record of episodic rapid sea-level rise during last deglaciation between Meltwater Pulses IA and IB

    Science.gov (United States)

    Khanna, P.; Droxler, A. W.; Nittrouer, J. A.; Tunnell, W.; Shirley, T. C.

    2013-12-01

    Some uppermost Pleistocene and Holocene drowned coralgal reefs and paleo-shorelines, globally distributed, document that sea level rise during last deglaciation was not gradual but rather episodic in nature. A recent high-resolution multi-beam survey imaged in details the bathymetry of ten drowned coralgal banks occurring along the South Texas Shelf edge. The bathymetric maps of each drowned bank display successive terraces representing typical back-stepping morphologies of coralgal banks struggling to keep up with episodes of rapid sea-level rise possibly related to ice sheet collapses. The ten drowned coralgal banks, some of them studied since the late 1950's, are lined up along a 110 km stretch of the south Texas continental shelf edge, located between the Rio Grande and the Brazos/Colorado River lowstand deltas. The depths of their exposed bases on the modern sea floor, ranging from 75 to 85 m, do not correspond to the bases of their initial growth. Their true thicknesses were only established through seismic imaging, because the lower third to half of the drowned coralgal edifices has been buried by the Texas Mud Blanket since ~8,000 years BP. The 40-50 m thick banks, established on lowstand coastal deposits since the beginning of the last deglaciation, are excellent archive for the upper most Pleistocene relative sea level rise. Extensive bathymetric data sets were collected in September 2012 during a two weeks-long research cruise, funded by the Schmidt Ocean Institute, on the R/V Falkor equipped with a Kongsberg EM 710 .5x1 degree multi-beam 100 kHz sonar, yielding resolution of less than 0.5 m. The newly established morphologies of the drowned banks offer new clues that the banks are truly coralgal reefs. For instance, the overall morphology of Dream Bank is typical of a small 2 km-wide atoll with a rimmed reef surrounding a shallow lagoon. Moreover sets of elongated channels, a few meters wide and deep, separated by 2-3 m wide ridges oriented ~90 deg

  12. 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

  13. Developing an IFC-based 3D Graphic Interactive Module by Utilizing Free Components%基于免费组件的IFC数据三维图形交互模块研究

    Institute of Scientific and Technical Information of China (English)

    魏振华; 马智亮

    2011-01-01

    基于BIM的三维图形交互模块的开发需解决BIM数据解析及三维模型显示两个问题,选择价格低廉甚至免费的组件并且能够进行高效的开发是研究者进行研究的最佳途径。本研究基于已有的BIM应用软件研究,针对IFC数据找到了一种能够用于快速高效地开发三维图形交互模块的免费组件组合,即TNO公司的IFCEngineDLL(用于BIM数据解析)和SIM公司的Coin3D(兼容OpenInventor,用于三维模型显示)。然后基于该组合,在C++语言开发环境下,研制了可以灵活用于BIM应用软件开发的三维图形交互模块3DGI,并进行了实际应用。本研究为利用免费组件自主研发轻量级的三维图形交互模块提供了一种快速高效的解决方案,从而可帮助研究者把更多的精力集中于进行BIM应用软件本身的研究中。%An IFC-based 3D graphic interactive module should include two key functions, i.e. accessing IFC data and displaying 3D model. In practice, researchers prefer to choose to use free-of-charge components which could provide the functions. In this paper, based on the comparison of several free-of-charge components, a combination of two free-of-charge components, i.e. IFC Engine DLL offered by TNO Building Research for accessing IFC data, and Coin3d offered by Kongsberg Oil & Gas Technologies for displaying graphics, was finally chosen. Then an IFC-based 3D graphic interactive module, called 3DGI, was developed by using only several hundreds of code lines in C + + language, and it could flexibly meet the requirements ule has been actually applied in the development of some BIM-based the determined combination is proved to be a quick, effective and of different BIM-based applications. The mod- applications by the authors. As a conclusion, free-of-charge solution to developing an IFC- based 3D graphic interactive module and it can help researchers reduce the efforts for developing the module

  14. Predicting seabed properties from acoustic backscatter on the UK continental shelf (Invited)

    Science.gov (United States)

    McGonigle, C.; Collier, J.

    2010-12-01

    The relationship between backscatter imagery, sediment grain size and measures of biological community diversity are investigated using a quantitative approach at an aggregate extraction site in the Southern North Sea, UK. Previous work conducted at Oban in Scotland (Collier and Brown, 2005) showed the potential for estimating sediment grain size from first order backscatter statistics. In particular this study reported r2 correlation values of 0.531 between mean backscatter and mean sediment grain size, with r2=0.351 between standard deviation backscatter and sediment grain size sorting (n=19). Here we test these simple linear relationships in a different environment where the sediments are coarser and the degree of sorting is lower. We present the analysis of a dataset collected in 2008 off the coast of East Anglia, UK. Beam-time series backscatter imagery was acquired from a 300 kHz source MBES (Kongsberg Simard EM3000D), and ground-truth data obtained from a series of 100 Hamon and 16 Clamshell grabs processed for particle size analysis. Pixels were extracted from 32-bit backscatter imagery at 50 m2 window based on the ground-truth data locations. So far 19 of the 100 Hamon samples have been processed. These show a significant correlation between mean backscatter intensity and mean sediment grain size (r2=0.427). The level of agreement between standard deviation backscatter and grain size distribution however, was lower at r2=0.078. Correlation of univariate measures of biological diversity and mean backscatter were low for the 19 samples; the maximum observed value was r2=0.074 (Fisher’s diversity index). Relative to the standard deviation backscatter, the strongest correlation was r2=0.192 (Brillion’s). The analysis of the Clamshell samples is completed. In this case, the MBES backscatter imagery established a stronger positive correlation (r2=0.628) between the means. The level of agreement observed between the standard deviation of the backscatter and

  15. 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.

  16. 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

  17. Pockmarks, fluid flow, and sediments outboard of the deformation front at the Cascadia Subduction Zone from analysis of multi-channel seismic and multi-beam sonar data

    Science.gov (United States)

    Gibson, J. C.; Carbotte, S. M.; Han, S.; Carton, H. D.; Canales, P.; Nedimovic, M. R.

    2013-12-01

    Evidence of active fluid flow and the nature of the sediment section near the Cascadia deformation front are explored using multi-channel (MCS) seismic and multi-beam sonar data collected in summer 2012 using the R/V Marcus G. Langseth during the Juan de Fuca Ridge to Trench Survey. The MCS data were collected along two full plate transects (the 'Oregon' and 'Washington' transects) and one trench parallel line using a 6600 cubic inch source, and an 8 km streamer with 636 channels (12.5 m spacing). The MCS data pre-stack processing sequence includes geometry definition, trace editing, F-K filter, and deconvolution. Velocity analysis is performed via semblance and constant velocity stacks in order to create a velocity model of the sediments and upper oceanic crust. The traces are then stacked, and post-stack time migrated. The sonar data were collected using the R/V Langseth's Kongsberg EM122 1°x1° multi-beam sonar with 288 beams and 432 total soundings across track. Using MB-system the sonar data are cleaned, and the bathymetry data are then gridded at 35 m, while the backscatter data are gridded at 15 m. From the high-resolution mapping data 48 pockmarks varying in diameter from 50 m - 1 km are identified within 60 km outboard of the deformation front. The surface expression of these large features in an area of heavy sedimentation is likely indicative of active fluid flow. In order to gain sub-seafloor perspective on these features the MCS data are draped below the bathymetry/backscatter grids using QPS Fledermaus. From this perspective, specific locations for detailed velocity and attribute analysis of the sediment section are chosen. Sediment velocity and attribute analysis also provide insight into apparent differences in the sediment section and décollement formation along the Oregon and Washington plate transects. While both lines intersect areas of dense pockmark concentration, the area around the Oregon transect has been shown to contain a continuous

  18. 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

  19. 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