Back to Collection NOAA/NESDIS/NGDC/MGG/Sonar_Water_Column

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referenceSystemInfo
identificationInfo
distributionInfo
dataQualityInfo
dataQualityInfo
acquisitionInformation

MARINER: Seismic Investigation of the Rainbow Hydrothermal Field (MGL1305, EM122)
 (MI_Metadata)
    fileIdentifier:  gov.noaa.ngdc.mgg.wcd:MGL1305_EM122
    language:  eng; USA
    characterSet:  (MD_CharacterSetCode) utf8
    hierarchyLevel:  (MD_ScopeCode) series
    hierarchyLevelName:  Water Column Sonar Series-Level Metadata
    contact:  (CI_ResponsibleParty)
        individualName:  Chuck Anderson
        organisationName:  DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce
        positionName:  Water Column Sonar Data Manager
        contactInfo:  (CI_Contact)
            phone:  (CI_Telephone)
                voice:  (303) 497-4742
            address:  (CI_Address)
                deliveryPoint:  325 Broadway, Mail Code E/NE42
                city:  Boulder
                administrativeArea:  CO
                postalCode:  80305-3328
                country:  USA
                electronicMailAddress:  wcd.info@noaa.gov
        role:  (CI_RoleCode) pointOfContact
    dateStamp:  2017-08-14
    metadataStandardName:  ISO 19115-2 Geographic Information - Metadata Part 2 Extensions for imagery and gridded data
    metadataStandardVersion:  ISO 19115-2:2009(E)
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    spatialRepresentationInfo:  (MD_VectorSpatialRepresentation)
        geometricObjects:  (MD_GeometricObjects)
            geometricObjectType:  (MD_GeometricObjectTypeCode) curve
            geometricObjectCount:  1435
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    referenceSystemInfo:  (MD_ReferenceSystem)
        referenceSystemIdentifier:  (RS_Identifier)
            authority:  (CI_Citation)
                title:  European Petroleum Survey Group (EPSG) Geodetic Parameter Registry
                date:  (CI_Date)
                    date:  2008-11-12
                    dateType:  (CI_DateTypeCode)
                citedResponsibleParty:  (CI_ResponsibleParty)
                    organisationName:  European Petroleum Survey Group
                    contactInfo:  (CI_Contact)
                        onlineResource:  (CI_OnlineResource)
                            linkage: http://www.epsg-registry.org/
                            name:  European Petroleum Survey Group Geodetic Parameter Dataset
                            description:  Registry that accesses the EPSG Geodetic Parameter Dataset, which is a structured dataset of Coordinate Reference Systems and Coordinate Transformations.
                            function:  (CI_OnLineFunctionCode) search
                    role: (inapplicable)
            code:  urn:ogc:def:crs:EPSG:4326
            version:  6.18.3
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    identificationInfo:  (MD_DataIdentification)
        citation:  (CI_Citation)
            title:  MARINER: Seismic Investigation of the Rainbow Hydrothermal Field (MGL1305, EM122)
            date:  (CI_Date)
                date:  2013-04-11
                dateType:  (CI_DateTypeCode) creation
            identifier:  (MD_Identifier)
                code:  MGL1305_EM122
            citedResponsibleParty:  (CI_ResponsibleParty)
                organisationName:  DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce
                role:  (CI_RoleCode) custodian
            citedResponsibleParty:  (CI_ResponsibleParty)
                organisationName:  NOAA National Centers for Environmental Information
                role:  (CI_RoleCode) publisher
            citedResponsibleParty:  (CI_ResponsibleParty)
                organisationName:  University-National Oceanographic Laboratory System (UNOLS)
                contactInfo:  (CI_Contact)
                    phone:  (CI_Telephone)
                        voice:  401-874-6825
                    address:  (CI_Address)
                        deliveryPoint:  15 South Ferry Road
                        city:  Narragansett
                        administrativeArea:  RI
                        postalCode:  02882
                        country:  USA
                        electronicMailAddress:  office@unols.org
                role:  (CI_RoleCode) resourceProvider
            citedResponsibleParty:  (CI_ResponsibleParty)
                organisationName:  University-National Oceanographic Laboratory System (UNOLS)
                contactInfo:  (CI_Contact)
                    phone:  (CI_Telephone)
                        voice:  401-874-6825
                    address:  (CI_Address)
                        deliveryPoint:  15 South Ferry Road
                        city:  Narragansett
                        administrativeArea:  RI
                        postalCode:  02882
                        country:  USA
                        electronicMailAddress:  office@unols.org
                role:  (CI_RoleCode) sponsor
        abstract:
        purpose:
        status:  (MD_ProgressCode) completed
        pointOfContact:  (CI_ResponsibleParty)
            individualName:  Juan Pablo Canales
            organisationName:  Woods Hole Oceanographic Institution
            positionName:  Associate Scientist
            contactInfo:  (CI_Contact)
                phone:  (CI_Telephone)
                    voice:  508-289-2893
                address:  (CI_Address)
                    deliveryPoint:  Woods Hole Oceanographic Institution
                    city:  Woods Hole
                    administrativeArea:  MA
                    postalCode:  02543
                    country:  USA
                    electronicMailAddress:  jcanales@whoi.edu
            role:  (CI_RoleCode) principalInvestigator
        pointOfContact:  (CI_ResponsibleParty)
            individualName:  Robert Dunn
            organisationName:  University of Hawaii
            positionName:  Professor
            contactInfo:  (CI_Contact)
                phone:  (CI_Telephone)
                    voice:  808-956-3728
                address:  (CI_Address)
                    deliveryPoint:  680 East-West Road
                    city:  Honolulu
                    administrativeArea:  HI
                    postalCode:  96822
                    country:  USA
                    electronicMailAddress:  dunnr@hawaii.edu
            role:  (CI_RoleCode) principalInvestigator
        resourceMaintenance:  (MD_MaintenanceInformation)
            maintenanceAndUpdateFrequency:  (MD_MaintenanceFrequencyCode) notPlanned
        descriptiveKeywords:  (MD_Keywords)
            keyword:  Earth Science > Oceans > Ocean Acoustics > Acoustic Scattering
            keyword:  Earth Science > Oceans > Aquatic Sciences > Fisheries
            keyword:  Earth Science > Oceans > Ocean Acoustics
            keyword:  Earth Science > Biosphere > Ecosystems > Marine Ecosystems > Pelagic
            keyword:  Earth Science > Biosphere > Ecosystems > Marine Ecosystems
            keyword:  Earth Science > Biosphere > Ecosystems > Marine Ecosystems > Benthic
            keyword:  Earth Science > Biosphere > Ecosystems > Aquatic Ecosystems
            keyword:  Earth Science > Oceans > Bathymetry/Seafloor Topography > Bathymetry
            keyword:  Earth Science > Oceans > Bathymetry/Seafloor Topography > Seafloor Topography
            type:  (MD_KeywordTypeCode) theme
            thesaurusName:  (CI_Citation)
                title:  Global Change Master Directory (GCMD) Science Keywords
                date:  (CI_Date)
                    date:  2018-03-15
                    dateType:  (CI_DateTypeCode) publication
                edition:  8.6
                citedResponsibleParty:  (CI_ResponsibleParty)
                    organisationName:  NASA Goddard Space Flight Center, Earth Science Data and Information System
                    contactInfo:  (CI_Contact)
                        onlineResource:  (CI_OnlineResource)
                            linkage: https://earthdata.nasa.gov/about/gcmd/global-change-master-directory-gcmd-keywords
                            name:  Global Change Master Directory (GCMD) Keywords
                            description:  The information provided on this page seeks to define how the GCMD Keywords are structured, used and accessed. It also provides information on how users can participate in the further development of the keywords.
                            function:  (CI_OnLineFunctionCode) information
                    role:  (CI_RoleCode) custodian
        descriptiveKeywords:  (MD_Keywords)
            keyword:  North Atlantic Ocean
            type:  (MD_KeywordTypeCode) place
            thesaurusName:  (CI_Citation)
                title:  International Hydrographic Organization (IHO) Sea Area ("Limits of Oceans and Seas" publication S-23)
                date:  (CI_Date)
                    date:  2010-08-24
                    dateType:  (CI_DateTypeCode) revision
                citedResponsibleParty:  (CI_ResponsibleParty)
                    organisationName:  International Hydrographic Organization (IHO) Sea Area ("Limits of Oceans and Seas" publication S-23)
                    contactInfo:  (CI_Contact)
                        onlineResource:  (CI_OnlineResource)
                            linkage: http://www.iho-ohi.net/iho_pubs/standard/S-23/S23_1953.pdf
                            name:  International Hydrographic Organization (IHO) Sea Area ("Limits of Oceans and Seas" publication S-23)
                            description:  Publication of Sea Areas is maintained by IHO.
                            function:  (CI_OnLineFunctionCode) information
                    role:  (CI_RoleCode) resourceProvider
        descriptiveKeywords:  (MD_Keywords)
            keyword:  DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce
            keyword:  DOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce
            type:  (MD_KeywordTypeCode) dataCenter
            thesaurusName:  (CI_Citation)
                title:  Global Change Master Directory (GCMD) Data Center Keywords
                date:  (CI_Date)
                    date:  2018-03-18
                    dateType:  (CI_DateTypeCode) publication
                edition:  8.6
                citedResponsibleParty:  (CI_ResponsibleParty)
                    organisationName:  NASA Goddard Space Flight Center, Earth Science Data and Information System
                    contactInfo:  (CI_Contact)
                        onlineResource:  (CI_OnlineResource)
                            linkage: https://earthdata.nasa.gov/about/gcmd/global-change-master-directory-gcmd-keywords
                            name:  Global Change Master Directory (GCMD) Keywords
                            description:  The information provided on this page seeks to define how the GCMD Keywords are structured, used and accessed. It also provides information on how users can participate in the further development of the keywords.
                            function:  (CI_OnLineFunctionCode) information
                    role:  (CI_RoleCode) custodian
        descriptiveKeywords:  (MD_Keywords)
            keyword:  Global
            keyword:  Vertical Location > Sea Floor
            type:  (MD_KeywordTypeCode) place
            thesaurusName:  (CI_Citation)
                title:  Global Change Master Directory (GCMD) Location Keywords
                date:  (CI_Date)
                    date:  2017-07-25
                    dateType:  (CI_DateTypeCode) publication
                edition:  8.6
                citedResponsibleParty:  (CI_ResponsibleParty)
                    organisationName:  NASA Goddard Space Flight Center, Earth Science Data and Information System
                    contactInfo:  (CI_Contact)
                        onlineResource:  (CI_OnlineResource)
                            linkage: https://earthdata.nasa.gov/about/gcmd/global-change-master-directory-gcmd-keywords
                            name:  Global Change Master Directory (GCMD) Keywords
                            description:  The information provided on this page seeks to define how the GCMD Keywords are structured, used and accessed. It also provides information on how users can participate in the further development of the keywords.
                            function:  (CI_OnLineFunctionCode) information
                    role:  (CI_RoleCode) custodian
        descriptiveKeywords:  (MD_Keywords)
            keyword:  In Situ/Laboratory Instruments > Profilers/Sounders > Acoustic Sounders > WCMS > Water Column Mapping System
            type:  (MD_KeywordTypeCode) instrument
            thesaurusName:  (CI_Citation)
                title:  Global Change Master Directory (GCMD) Instrument Keywords
                date:  (CI_Date)
                    date:  2018-02-27
                    dateType:  (CI_DateTypeCode) publication
                edition:  8.6
                citedResponsibleParty:  (CI_ResponsibleParty)
                    organisationName:  NASA Goddard Space Flight Center, Earth Science Data and Information System
                    contactInfo:  (CI_Contact)
                        onlineResource:  (CI_OnlineResource)
                            linkage: https://earthdata.nasa.gov/about/gcmd/global-change-master-directory-gcmd-keywords
                            name:  Global Change Master Directory (GCMD) Keywords
                            description:  The information provided on this page seeks to define how the GCMD Keywords are structured, used and accessed. It also provides information on how users can participate in the further development of the keywords.
                            function:  (CI_OnLineFunctionCode) information
                    role:  (CI_RoleCode) custodian
        resourceConstraints:  (MD_LegalConstraints)
            useConstraints:  (MD_RestrictionCode) otherRestrictions
            otherConstraints:  Cite as: Rolling Deck to Repository (R2R) Program (2013): Water Column Sonar Data Collection (MGL1305, EM122). National Centers for Environmental Information, NOAA. [access date]
        resourceConstraints:  (MD_LegalConstraints)
            accessConstraints:  (MD_RestrictionCode) otherRestrictions
            otherConstraints:  Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives.
        resourceConstraints:  (MD_Constraints)
            useLimitation:  These data are considered raw and have not been subjected to the NOAA's quality control or quality assurance procedures. They are released for limited public use as preliminary data to be used only with appropriate caution. NOAA cannot assume liability for any damages caused by any errors or omissions in the data, nor as a result of the failure of the data to function on a particular system. NOAA makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty.
        resourceConstraints:  (MD_Constraints)
            useLimitation:  Not subject to copyright protection within the United States.
        resourceConstraints:  (MD_LegalConstraints)
            accessConstraints:  (MD_RestrictionCode) otherRestrictions
            otherConstraints:  Resource may not be available for up to one year after initial collection.
        aggregationInfo:  (MD_AggregateInformation)
            aggregateDataSetIdentifier:  (MD_Identifier)
                code:  MGL1305
            associationType:  (DS_AssociationTypeCode) largerWorkCitation
            initiativeType:  (DS_InitiativeTypeCode) operation
        language:  eng; USA
        topicCategory:  (MD_TopicCategoryCode) oceans
        topicCategory:  (MD_TopicCategoryCode) geoscientificInformation
        extent:  (EX_Extent)
            geographicElement:  (EX_GeographicBoundingBox)
                westBoundLongitude:  -64.56203
                eastBoundLongitude:  -33.28345
                southBoundLatitude:  32.38957
                northBoundLatitude:  36.71617
            temporalElement:  (EX_TemporalExtent)
                extent:
                  TimePeriod:
                    beginPosition:  2013-04-11T22:38:30
                    endPosition:  2013-05-17T16:52:24
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    distributionInfo:  (MD_Distribution)
        distributionFormat:  (MD_Format)
            name:  Kongsberg EM122 water column data (.wcd) format
            version:  1
            specification:  Kongsberg EM122 .wcd files. See the EM122 documentation for detailed format specification. Note: frequently navigation datagrams are not recorded in the EM122 .wcd files. See corresponding .all file for navigation data.
        distributor:  (MD_Distributor)
            distributorContact:  (CI_ResponsibleParty)
                individualName:  Chuck Anderson
                organisationName:  DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce
                positionName:  Water Column Sonar Data Manager
                contactInfo:  (CI_Contact)
                    phone:  (CI_Telephone)
                        voice:  (303) 497-4742
                    address:  (CI_Address)
                        deliveryPoint:  325 Broadway, Mail Code E/NE42
                        city:  Boulder
                        administrativeArea:  CO
                        postalCode:  80305-3328
                        country:  USA
                        electronicMailAddress:  wcd.info@noaa.gov
                role:  (CI_RoleCode) pointOfContact
            distributionOrderProcess:  (MD_StandardOrderProcess)
                fees:  Free
                orderingInstructions:  Contact the NCEI Water Column Sonar Data Manager to order data
        transferOptions:  (MD_DigitalTransferOptions)
            onLine:  (CI_OnlineResource)
                linkage: http://maps.ngdc.noaa.gov/viewers/water_column_sonar/
                name:  Water Column Sonar Data Map Viewer
                description:  Interactive map viewer to allow discovery and access to water column sonar data
                function:  (CI_OnLineFunctionCode) search
        transferOptions:  (MD_DigitalTransferOptions)
            onLine:  (CI_OnlineResource)
                linkage: http://www.ngdc.noaa.gov/mgg/wcd
                name:  Water Column Sonar Data Archive Homepage
                description:  Web page containing information on the water column sonar data archive.
                function:  (CI_OnLineFunctionCode) information
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    dataQualityInfo:  (DQ_DataQuality)
        scope:  (DQ_Scope)
            level:  (MD_ScopeCode) collectionHardware
            levelDescription:  (MD_ScopeDescription)
                other:  Instrument calibration information
        lineage:  (LI_Lineage)
            statement:  Unknown
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    dataQualityInfo:  (DQ_DataQuality)
        scope:  (DQ_Scope)
            level:  (MD_ScopeCode) series
        report:  (DQ_AbsoluteExternalPositionalAccuracy)
            nameOfMeasure:  Horizontal Positional Accuracy
            result:  (DQ_ConformanceResult)
                specification: (inapplicable)
                explanation:  Positional accuracy dependent on navigation GPS, ship motion correction, and sound velocity profile accuracy.
                pass:  true
        report:  (DQ_AbsoluteExternalPositionalAccuracy)
            nameOfMeasure:  Vertical Positional Accuracy
            result:  (DQ_ConformanceResult)
                specification: (inapplicable)
                explanation:  Vertical accuracy is dependent on navigation GPS and ship motion corrections.
                pass:  true
        lineage:  (LI_Lineage)
            processStep:  (LI_ProcessStep)
                description:  Raw unprocessed data files
                dateTime:
                  DateTime:  2013-04-11T22:38:30
                processor:  (CI_ResponsibleParty)
                    individualName:  Juan Pablo Canales
                    organisationName:  Woods Hole Oceanographic Institution
                    positionName:  Associate Scientist
                    contactInfo:  (CI_Contact)
                        phone:  (CI_Telephone)
                            voice:  508-289-2893
                        address:  (CI_Address)
                            deliveryPoint:  Woods Hole Oceanographic Institution
                            city:  Woods Hole
                            administrativeArea:  MA
                            postalCode:  02543
                            country:  USA
                            electronicMailAddress:  jcanales@whoi.edu
                    role:  (CI_RoleCode) principalInvestigator
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    acquisitionInformation:  (MI_AcquisitionInformation)
        instrument:  (MI_Instrument)
            citation:  (CI_Citation)
                title:  Kongsberg EM122 Multibeam Echosounder
                date: (unknown)
                identifier:  (MD_Identifier)
                    code:  EM122
                citedResponsibleParty:  (CI_ResponsibleParty)
                    organisationName:  Kongsberg Maritime
                    contactInfo:  (CI_Contact)
                        phone:  (CI_Telephone)
                            voice:  +47 214 98 364
                            facsimile:  +47 322 85 014
                        address:  (CI_Address)
                            deliveryPoint:  P.O. Box 483
                            deliveryPoint:  NO-3601
                            city:  Kongsberg
                            country:  Norway
                            electronicMailAddress:  km.support@kongsberg.com
                        onlineResource:  (CI_OnlineResource)
                            linkage: http://www.km.kongsberg.com/ks/web/nokbg0240.nsf/AllWeb/01FB0F22974EA50FC125715E002B2143?OpenDocument
                            name:  Kongsberg EM122 information
                            description:  Information on the Kongsberg EM122 multibeam sonar system
                            function:  (CI_OnLineFunctionCode) information
                    role:  (CI_RoleCode) resourceProvider
            identifier:  (MD_Identifier)
                code:  Kongsberg EM122
            type:  Multibeam Echosounder
            description:  EM 122 multibeam echosounder is a high performance echosounder for deep water mapping with up to 288 simultaneous beams. The EM 122 is designed to perform seabed mapping to full ocean depth with an unsurpassed resolution, coverage and accuracy. The system is cost effective, reliable, and easily operated. The design of the EM 122 is based on more than 50 years of hydrographic experience with echo sounders, sonars and underwater positioning for civilian and military use. It is the latest model in a series of deep sea multibeam echo sounders started with the EM 12 in 1990 and followed by the EM 121 and the EM 120, of which about 40 systems are operational. It uses the same transducers as in the EM 120 but with new electronics and software. Compared with the EM 120 the EM 122 has up to four times the resolution in terms of sounding density through inclusion of multiping capability and more than twice the number of detections per swath. High density signal processing is a major improvement, to keep the acoustic footprint size small even for the outer beams in the swath. In typical ocean depths a sounding spacing of about 50 m across and along is achievable. The achievable swath width of the EM 122 is in the order of 30,000 m, or about 25% more than possible with the EM 120. This is obtained by using long FM chirps which gains about 15 dB in signal to noise ratio compared to CW pulses. The EM 122 is a complete system. All necessary sensor interfaces, data displays for quality control and sensor calibration, seabed visualization, and data logging are a standard part of the system, as is integrated seabed acoustical imaging capability (side scan). Including a higher frequency multibeam echo sounder such as EM 710 with the EM 122 system can give a total system solution meeting the strictest IHO requirements for all water depths. As proven with the EM 120, an accuracy of better than 0.2% of depth in deep waters is readily achievable with the EM 122.
        operation:  (MI_Operation)
            identifier:  (MD_Identifier)
                code:  MGL1305_EM122
            status:  (MD_ProgressCode) completed
            parentOperation: (inapplicable)
        platform:  (MI_Platform)
            citation:  (CI_Citation)
                title:  R/V Marcus G. Langseth
                date: (inapplicable)
            identifier:  (MD_Identifier)
                code:  Marcus G. Langseth
            description:  The Marcus G. Langseth serves as the national seismic research facility for the United States academic research community. The R/V Marcus G. Langseth's unique seismic capability allows it to provide both 2D and 3D maps of the earth's structure miles below the seafloor. Utilizing the vessel's other capabilities, expeditions have collected sediment cores for understanding climate variations throughout the Earth'™s history, sampled seawater for determining physical and chemical properties of the oceans, and deployed remotely operated vehicles (ROVs) for studying submarine volcanoes. Scientists and researchers from all over the world are encouraged to participate in research programs aboard the Langseth.
            sponsor:  (CI_ResponsibleParty)
                organisationName:  Lamont-Doherty Earth Observatory - Office of Marine Operations
                contactInfo:  (CI_Contact)
                    phone:  (CI_Telephone)
                        voice:  (845) 359-2900
                    address:  (CI_Address)
                        deliveryPoint:  P.O. Box 1000
                        deliveryPoint:  61 Route 9W
                        city:  Palisades
                        administrativeArea:  NY
                        postalCode:  10964-1000
                        country:  USA
                        electronicMailAddress:  director@ldeo.columbia.edu
                role:  (CI_RoleCode) resourceProvider
            instrument:  (MI_Instrument)
                citation:  (CI_Citation)
                    title:  Kongsberg EM122 Multibeam Echosounder
                    date: (unknown)
                    identifier:  (MD_Identifier)
                        code:  EM122
                    citedResponsibleParty:  (CI_ResponsibleParty)
                        organisationName:  Kongsberg Maritime
                        contactInfo:  (CI_Contact)
                            phone:  (CI_Telephone)
                                voice:  +47 214 98 364
                                facsimile:  +47 322 85 014
                            address:  (CI_Address)
                                deliveryPoint:  P.O. Box 483
                                deliveryPoint:  NO-3601
                                city:  Kongsberg
                                country:  Norway
                                electronicMailAddress:  km.support@kongsberg.com
                            onlineResource:  (CI_OnlineResource)
                                linkage: http://www.km.kongsberg.com/ks/web/nokbg0240.nsf/AllWeb/01FB0F22974EA50FC125715E002B2143?OpenDocument
                                name:  Kongsberg EM122 information
                                description:  Information on the Kongsberg EM122 multibeam sonar system
                                function:  (CI_OnLineFunctionCode) information
                        role:  (CI_RoleCode) resourceProvider
                identifier:  (MD_Identifier)
                    code:  Kongsberg EM122
                type:  Multibeam Echosounder
                description:  EM 122 multibeam echosounder is a high performance echosounder for deep water mapping with up to 288 simultaneous beams. The EM 122 is designed to perform seabed mapping to full ocean depth with an unsurpassed resolution, coverage and accuracy. The system is cost effective, reliable, and easily operated. The design of the EM 122 is based on more than 50 years of hydrographic experience with echo sounders, sonars and underwater positioning for civilian and military use. It is the latest model in a series of deep sea multibeam echo sounders started with the EM 12 in 1990 and followed by the EM 121 and the EM 120, of which about 40 systems are operational. It uses the same transducers as in the EM 120 but with new electronics and software. Compared with the EM 120 the EM 122 has up to four times the resolution in terms of sounding density through inclusion of multiping capability and more than twice the number of detections per swath. High density signal processing is a major improvement, to keep the acoustic footprint size small even for the outer beams in the swath. In typical ocean depths a sounding spacing of about 50 m across and along is achievable. The achievable swath width of the EM 122 is in the order of 30,000 m, or about 25% more than possible with the EM 120. This is obtained by using long FM chirps which gains about 15 dB in signal to noise ratio compared to CW pulses. The EM 122 is a complete system. All necessary sensor interfaces, data displays for quality control and sensor calibration, seabed visualization, and data logging are a standard part of the system, as is integrated seabed acoustical imaging capability (side scan). Including a higher frequency multibeam echo sounder such as EM 710 with the EM 122 system can give a total system solution meeting the strictest IHO requirements for all water depths. As proven with the EM 120, an accuracy of better than 0.2% of depth in deep waters is readily achievable with the EM 122.