{
    "tag": 15624,
    "title": "Surface sediment grain size distributions derived from manual point counts of in situ seafloor images from the lower Columbia River, Washington and Oregon, 2021",
    "pubdate": "20230808",
    "sername": null,
    "series_name": null,
    "issue": "DOI:10.5066\/10.5066\/P92U1KPY",
    "publish": null,
    "publisher_name": null,
    "onlink": "https:\/\/cmgds.marine.usgs.gov\/catalog\/pcmsc\/DataReleases\/CMGDS_DR_tool\/DR_P92U1KPY\/point_count_distributions_metadata.faq.html",
    "format": null,
    "email": null,
    "descript": "This dataset contains surface sediment grain size distributions derived from manual point counts of in situ seafloor images obtained with an underwater camera system in the lower Columbia River, Washington and Oregon, in 2021. The distributions derived from manual point counts were compared with results from an automated image processing technique to calibrate and validate the automated method used to quantify surface sediment grain size distributions in objective images. The surface sediment grain size distribution data derived from manual point counts are provided in comma-separated text format (point_count_distributions.csv) and should be compared with grain size distributions for the same set of images (dgs_calibration_validation.csv) derived from automated image processing that can be found in the \"Surface sediment grain size distributions derived from automated image processing of in situ seafloor images from the lower Columbia River, Washington and Oregon, 2021\" portion of the overall data release.",
    "lang": null,
    "journal": null,
    "pwid": null,
    "originator": [
        {
            "name": "Stevens, Andrew W.",
            "role": "Author"
        },
        {
            "name": "Hatcher, Gerald A.",
            "role": "Author"
        },
        {
            "name": "Dal Ferro, Peter",
            "role": "Author"
        },
        {
            "name": "Dartnell, Peter",
            "role": "Author"
        },
        {
            "name": "Warrick, Jonathan A.",
            "role": "Author"
        },
        {
            "name": "Cohn, Nicholas",
            "role": "Author"
        },
        {
            "name": "Moritz, Hans R.",
            "role": "Author"
        }
    ],
    "index_term": [
        {
            "thcode": 2,
            "code": "493",
            "name": "grain-size analysis",
            "scope": "Method of studying soils, sediments, sands, or rock by determining the size, distribution, and proportion of selected particles."
        },
        {
            "thcode": 2,
            "code": "816",
            "name": "ocean processes",
            "scope": "Recurrent natural changes that are physical, biological, or chemical, actively affecting the seas and oceans."
        },
        {
            "thcode": 2,
            "code": "1034",
            "name": "sediment transport",
            "scope": "Transport of solid particles of unconsolidated rock and mineral fragments, chemical precipitates, or biological materials."
        },
        {
            "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": 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": "417",
            "name": "Global Positioning System (GPS) observations",
            "scope": "the use of satellite signals from the Global Positioning System to determine the precise location of a terrestrial receiver."
        },
        {
            "thcode": 61,
            "code": "220",
            "name": "sediment",
            "scope": "unconsolidated weathering products that have been eroded, transported, and deposited in another location."
        }
    ],
    "place_term": [],
    "image": [],
    "fan": [
        "2021-621-FA"
    ]
}