{
    "tag": 14789,
    "title": "Multibeam bathymetry and acoustic backscatter data from the Alaskan region, Extended Continental Shelf Project, 2011 field season: Gulf of Alaska and Bering Sea",
    "pubdate": "20220825",
    "sername": null,
    "series_name": null,
    "issue": "DOI: 10.5066\/F7HM56HK",
    "publish": null,
    "publisher_name": null,
    "onlink": "https:\/\/cmgds.marine.usgs.gov\/catalog\/pcmsc\/DataReleases\/ScienceBase\/DR_F7HM56HK\/Langseth2011overview.faq.html",
    "format": null,
    "email": null,
    "descript": "This publication releases swath bathymetry and backscatter datasets derived from multibeam bathymetric data acquired by the U.S. Geological Survey (USGS) on the R\/V Marcus G. Langseth legs MGL1108 (transit) and MGL1109 in the Gulf of Alaska, and MGL1111 in the Bering Sea. These data were acquired with a Kongsberg Simrad EM-122 multibeam echosounder and Seafloor Information System (SIS) acquisition software.   The MGL1108 data were combined with the MGL1109 data during processing and are presented as MGL1109. This data set includes 100-m bathymetry grids generated from processed bathymetry soundings, 100-m backscatter grids generated from coregistered processed backscatter values, extracted center beam bathymetry soundings, and associated metadata. The Gulf of Alaska lines extend from 48.27\u00b0 N to 57.71\u00b0 N, 137.81\u00b0 W to 152.38\u00b0 W in the northeastern Pacific, including portions of the distal Surveyor and Baranof fan systems, Kodiak-Bowie seamounts, and Aleutian trench near Kodiak Island, AK. The Bering Sea lines extend from 54.04\u00b0 N to 58.88\u00b0 N, 166.56\u00b0 W to 174.04\u00b0 E, including portions of the Umnak Plateau northwest of Dutch Harbor, AK, central Aleutian Basin, distal eastern flank of Shirshov Ridge, and north face of Bowers Ridge.  These surveys were designed primarily for acquisition of multichannel seismic-reflection imaging and ocean-bottom seismometer OBS velocity analysis in support of Extended Continental Shelf (ECS) maritime zone definition. The USGS activities in mapping the ECS are coordinated through the interagency ECS Task Force, comprising representatives from the U.S. Department of State, the USGS, the National Oceanographic and Atmospheric Administration (NOAA), and several other governmental agencies. Further information on the U.S. Extended Continental Shelf (ECS) Project and its activities is posted at https:\/\/www.state.gov\/e\/oes\/ocns\/opa\/ecs\/index.htm.",
    "lang": null,
    "journal": null,
    "pwid": null,
    "originator": [
        {
            "name": "Barth, Ginger",
            "role": "Author"
        },
        {
            "name": "Baldwin, Wayne E.",
            "role": "Author"
        },
        {
            "name": "Reece, Robert S.",
            "role": "Author"
        },
        {
            "name": "Gulick, Sean S.",
            "role": "Author"
        },
        {
            "name": "Danforth, William W.",
            "role": "Author"
        },
        {
            "name": "Wong, Florence L.",
            "role": "Author"
        }
    ],
    "index_term": [
        {
            "thcode": 2,
            "code": "80",
            "name": "bathymetry",
            "scope": "The elevation of the earth's surface beneath a body of water, especially the ocean, typically determined by measurements of depth from the water surface."
        },
        {
            "thcode": 2,
            "code": "82",
            "name": "bathymetry measurement",
            "scope": "Means of determining the depth to the floor of a body of water, especially the ocean."
        },
        {
            "thcode": 2,
            "code": "474",
            "name": "geospatial datasets",
            "scope": "Collections of related digital information that are geographically referenced."
        },
        {
            "thcode": 2,
            "code": "2046",
            "name": "image mosaics",
            "scope": "Composite images formed by overlapping existing images, typically arranged to achieve greater spatial coverage."
        },
        {
            "thcode": 2,
            "code": "707",
            "name": "marine geophysics",
            "scope": "Branch of earth sciences concerned with the physical processes of the oceans and continental margins.  We include here studies of large bodies of brackish and fresh water, such as lakes and rivers."
        },
        {
            "thcode": 2,
            "code": "2036",
            "name": "multibeam sonar",
            "scope": "Acoustic technique for determining depths or creating backscatter imagery in a wide swath of seafloor or lakebed centered below the instrument platform."
        },
        {
            "thcode": 2,
            "code": "2053",
            "name": "sea-floor acoustic reflectivity",
            "scope": "Acoustic energy received by a sonar system, providing a measure of the roughness of the sea floor."
        },
        {
            "thcode": 2,
            "code": "1025",
            "name": "sea-floor characteristics",
            "scope": "Geomorphic features and geographic, compositional, and textural variation in the materials composing the ocean floor. Includes both large-scale structures (such as seamounts and rises) and fine-scale variations in rocks and deposits on the sea floor."
        },
        {
            "thcode": 2,
            "code": "1045",
            "name": "seismic reflection methods",
            "scope": "Geophysical technique to study the subsurface of the earth using sound waves induced by explosives, vibrating devices, or percussive equipment.  The reflections of the sound waves from the boundaries of different rocks are measured."
        },
        {
            "thcode": 15,
            "code": "007",
            "name": "environment",
            "scope": "Environmental resources, protection and conservation, for example environmental pollution, waste storage and treatment, environmental impact assessment, monitoring environmental risk, nature reserves, landscape, water quality, air quality, environmental modeling"
        },
        {
            "thcode": 15,
            "code": "008",
            "name": "geoscientificInformation",
            "scope": "Information pertaining to earth sciences, for example geophysical features and processes, geology, minerals, sciences dealing with the composition, structure and origin of the earth's rocks, risks of earthquakes, volcanic activity, landslides, gravity information, soils, permafrost, hydrogeology, groundwater, erosion"
        },
        {
            "thcode": 15,
            "code": "014",
            "name": "oceans",
            "scope": "Features and characteristics of salt water bodies (excluding inland waters), for example tides, tidal waves, coastal information, reefs, maritime, outer continental shelf submerged lands, shoreline"
        },
        {
            "thcode": 23,
            "code": "22",
            "name": "Bathymetry and Elevation",
            "scope": "Includes measures of the height of a location above or below a reference surface. Bathymetry is the elevation of the Earth's surface beneath a body of water, especially the ocean, typically determined by measurements of depth from the water surface at mean lower low water. Distributions are topographic maps and bathymetric charts based on collected data and also include smoothed or gridded maps of bathymetry and elevation from observational data or other associated factors. Assessment data types include models of ecological value, economic value, or current rates of alterations due to erosion, accretion, climate change, and other stressors (for example, wetland habitat loss). Predictions are the results of models or projections of future distributions, values, or ecological impacts of bathymetry, including predicted changes due to natural and human forces such as erosion, deposition, sea-level rise, and dredging activities; predictions also include the results of scenario-based models of bathymetry changes under different management strategies."
        },
        {
            "thcode": 23,
            "code": "21",
            "name": "Physical Habitats and Geomorphology",
            "scope": "Includes measures of the geologic and structural characteristics of the coast or sea floor, such as the features defined in the Geoform Component of CMECS. Distributions are detailed topographic and bathymetric maps, geolocated photographs, or sea-floor descriptions; Distributions includes maps that interpret observations to categorize areas on the basis of geoform types such as those in CMECS. Assessment types include evaluations of ecological or human use value and can include models that project environmental or economic effects of erosion, climate change, dredging, and other stressors. Predictions are the results of models or projections of future distributions, values, or ecological impacts of physical habitats, including predicted changes due to natural and human forces; they are also from scenario-based models of resource losses, gains, or impacts on ecological or economic values under different management strategies (for example, mining, removal, relocation, or the building of structures)."
        },
        {
            "thcode": 23,
            "code": "23",
            "name": "Substrate",
            "scope": "Represents the character and composition of the surface and near surface of the sea floor in subtidal or intertidal areas, as defined in the Substrate Component of CMECS or in similar classification systems. Distributions are records of substrate characteristics based on visual or photographic inspection or on analysis of samples and cores, and they also include interpretive maps classifying areas on the basis of combinations of observations, hydrodynamic models, or geological models. Assessments include evaluations of present ecological or economic values of substrate distributions, drivers of substrate change, and functions of substrates. Predictions are the results of models or projections of future substrate distributions, values, or ecological impacts, including predicted substrate changes due to natural and human forces including erosion, accretion, sea-level change, extraction, trawling, or other factors; and they are the results of scenario-based models of substrate changes on ecological or economic values under different management strategies or other human alterations."
        },
        {
            "thcode": 61,
            "code": "123",
            "name": "continental shelf",
            "scope": "the gently sloping sea floor between the coast and the continental slope."
        },
        {
            "thcode": 61,
            "code": "738",
            "name": "marine geophysics",
            "scope": "used for geophysical and related studies of ocean basins and margins."
        },
        {
            "thcode": 61,
            "code": "402",
            "name": "multibeam echo sounder",
            "scope": "acoustic technique for determining sea-floor depths in a wide swath centered below the instrument platform."
        },
        {
            "thcode": 61,
            "code": "478",
            "name": "seismic methods",
            "scope": "the study of naturally occurring or artificially induced seismic waves, generally for one of two purposes: 1) understanding the nature and cause of seismic activity (e.g., earthquakes), or 2) understanding the properties of the earth materials through which the seismic waves have passed."
        }
    ],
    "place_term": [],
    "image": [
        {
            "name": "https:\/\/www.sciencebase.gov\/catalog\/file\/get\/55d23737e4b0518e35468abd?name=Langseth2011overview.jpg&allowOpen=true",
            "description": "R\/V Marcus G. Langseth 2011 footprint of bathymetry and backscatter data for the Gulf of Alaska and Bering Sea"
        }
    ],
    "fan": []
}