{
    "tag": 7924,
    "title": "Subbottom and Sidescan Sonar Data Acquired in 2015 From Grand Bay, Mississippi and Alabama",
    "pubdate": "20181001",
    "sername": null,
    "series_name": null,
    "issue": "doi:10.5066\/P9374DKQ",
    "publish": null,
    "publisher_name": null,
    "onlink": "https:\/\/cmgds.marine.usgs.gov\/catalog\/spcmsc\/GrandBay_2015-315-FA_metadata.faq.html",
    "format": null,
    "email": null,
    "descript": "From May 28 to June 3, 2015, the U.S. Geological Survey (USGS) conducted a geophysical survey to investigate the geologic evolution and estuarine sediment thickness in Grand Bay, Alabama and Mississippi. Specific objectives were to document the age and accumulation patterns of estuarine sediment to advance our understanding of sediment exchange with the adjacent marsh and sources of sediment to the coastal ocean. This investigation is part of the USGS Sea-level and Storm Impacts on Estuarine Environments and Shorelines (SSIEES) project. SSIEES seeks to better understand material exchange between marshes and adjacent estuarine water bodies along the northern Gulf of Mexico and the Atlantic coast, and determine the role extreme events (hurricanes, floods, and strong frontal systems) and sea-level change have on coastal change. This publication serves as an archive of unprocessed, digital chirp subbottom and sidescan sonar data, geographic information system (GIS) data and formal Federal Geographic Data Committee (FGDC) metadata, as well as processed sidescan sonar mosaics. Processed subbottom profile images are also provided in the \"images\" folder of 2015-315-FA_arc.zip. The archived subbottom trace data are in standard Society of Exploration Geophysicists (SEG) SEG Y revision 0 format (Barry and others, 1975) and may be downloaded and processed with commercial or public domain software such as Seismic Unix (SU). The raw sidescan sonar backscatter data are in standard eXtensible Triton Framework (XTF)format. These data are available for viewing using GeoMapApp (http:\/\/www.geomapapp.org\/) and Virtual Ocean (http:\/\/www.virtualocean.org\/) multi-platform open source software. In addition, these data files can be downloaded from the USGS Coastal and Marine Geoscience Data System (https:\/\/cmgds.marine.usgs.gov).",
    "lang": null,
    "journal": null,
    "pwid": null,
    "originator": [
        {
            "name": "Locker, Stanley D.",
            "role": "Author"
        },
        {
            "name": "Forde, Arnell S.",
            "role": "Author"
        },
        {
            "name": "Smith, Christopher G.",
            "role": "Author"
        }
    ],
    "index_term": [
        {
            "thcode": 2,
            "code": "1799",
            "name": "coastal processes",
            "scope": "Processes unique to coastal areas including longshore transport, beach erosion, storm surge, shoreline change, delta formation, barrier island migration, beach stabilization by vegetation"
        },
        {
            "thcode": 2,
            "code": "358",
            "name": "estuarine ecosystems",
            "scope": "Biological communities and habitats within sea inlets or the zones where rivers meet the seas which are subject to tidal effects and the mixture of fresh and saltwater."
        },
        {
            "thcode": 2,
            "code": "464",
            "name": "geology",
            "scope": "Study of the planet earth, its composition, structure, physical and chemical processes, and history since its origin."
        },
        {
            "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": "706",
            "name": "marine geology",
            "scope": "Branch of geology concerned with the composition, geologic history, and earth processes of the ocean floor and the continental margin."
        },
        {
            "thcode": 2,
            "code": "2038",
            "name": "sidescan sonar",
            "scope": "Acoustic technique for creating oblique backscatter imagery of the seafloor or lakebed."
        },
        {
            "thcode": 2,
            "code": "2054",
            "name": "sub-bottom profiling",
            "scope": "Methods of imaging the structure of sediments below the sea floor  or lakebed using ship-borne or towed sensors with a variety of sound sources."
        },
        {
            "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": "3",
            "name": "Distributions",
            "scope": "Locations or patterns of a feature of interest across space and (or) time. These data can include point data, lines, polygons, and temporal data at any scale relevant to CMSP and can be produced by observation, interpolation, or modeling. Distributions can also include maps or statistics of climatology, the environmental values that are expected to be observed at the present time."
        },
        {
            "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": 61,
            "code": "479",
            "name": "seismic reflection profiling",
            "scope": "technique for determining the composition and structure of subsurface earth materials based on the transmission and reflection of artificially induced seismic waves; in practice, the seismic waves are generated and received at a one location (in marine geophysical studies, a single ship)."
        }
    ],
    "place_term": [],
    "image": [],
    "fan": []
}