{"accessLevel": "public", "bureauCode": ["010:12"], "contactPoint": {"@type": "vcard:Contact", "fn": "Margaret E. Berry", "hasEmail": "mailto:meberry@usgs.gov"}, "description": "The Fort Morgan 7.5' quadrangle is located on the semiarid plains\nof northeastern Colorado, along the South Platte River corridor where the\nriver has incised into Upper Cretaceous Pierre Shale. The Pierre Shale is\nlargely covered by surficial deposits that formed from alluvial, eolian,\nand hillslope processes operating in concert with environmental changes\nfrom the late Pliocene to the present. The South Platte River, originating\nhigh in the Colorado Rocky Mountains, has played a major role in shaping\nsurficial geology in the map area, which is several tens of kilometers\ndownstream from where headwater tributaries join the river. Recurrent\nglaciation (and deglaciation) of basin headwaters has affected river\ndischarge and sediment supply far downstream, influencing deposition of\nalluvium and river incision in the Fort Morgan quadrangle. Distribution and\ncharacteristics of the alluvial deposits indicate that during the\nPleistocene the course of the river within the map area shifted progressively\nsouthward as it incised, and by late middle Pleistocene the river was south\nof its present position, cutting and filling a deep paleochannel near the\nsouth edge of the quadrangle. The river shifted back to the north during the\nlate Pleistocene. Kiowa and Bijou Creeks are unglaciated tributaries\noriginating in the Colorado Piedmont east of the Front Range that also have\nplayed a major role in shaping surficial geology of the map area. Periodically\nduring the late Pleistocene, major flood events on these tributaries deposited\nlarge volumes of sediment at and near their confluences, forming a broad, low-\ngradient fan composed of sidestream alluvium that could have occasionally\ndammed the river for short periods of time. Wildcat Creek, also originating\non the Colorado Piedmont, and the small drainage of Cris Lee Draw dissect the\nmap area north of the river. Eolian sand deposits of the Sterling (north of\nriver) and Fort Morgan (south of river) dune fields cover much of the\nquadrangle and record past episodes of sand mobilization during times of\nprolonged drought. With the onset of irrigation and damming during historical\ntimes, the South Platte River has changed from a broad, shallow, and sandy\nbraided river with highly variable seasonal discharge to a much narrower,\ndeeper river with braided-meandering transition morphology and more uniform\ndischarge.", "distribution": [{"@type": "dcat:Distribution", "accessURL": "https://doi.org/10.5066/F7QC02PQ", "description": "Landing page for access to the data", "format": "XML", "mediaType": "application/http", "title": "Digital Data"}, {"@type": "dcat:Distribution", "description": "The metadata original format", "downloadURL": "https://data.usgs.gov/datacatalog/metadata/USGS.5a02006fe4b0531197b72d31.xml", "format": "XML", "mediaType": "text/xml", "title": "Original Metadata"}], "identifier": "http://datainventory.doi.gov/id/dataset/USGS_5a02006fe4b0531197b72d31", "keyword": ["Bijou Creek", "Bijou No 2 Reservoir", "Broadway Alluvium", "Bull Lake glaciation", "Colorado", "Cretaceous", "Empire Reservoir", "Fort Morgan", "Front Range", "Greeley", "Holocene", "Jackson Reservoir", "Kersey", "Kiowa Creek", "Laramie Formation", "Louviers Alluvium", "Masters", "Milliron Draw", "Morgan County", "Nussbaum Alluvium", "OSL", "Orchard", "Peoria Loess", "Pierre Shale", "Pinedale glaciation", "Piney Creek Alluvium", "Pleistocene", "Pliocene", "Quaternary", "Rocky Flats Alluvium", "Slocum Alluvium", "South Platte River", "U-series", "USA", "USGS:5a02006fe4b0531197b72d31", "United States", "Verdos Alluvium", "Weld County", "Weldona", "Wildcat Creek", "alluvium", "argillic B horizon", "braided", "colluvium", "discharge", "dune", "eolian", "floodplain", "geologic map", "lignite", "luminescence", "meandering", "radiocarbon", "sand sheet", "sheetflood", "soil", "terrace"], "modified": "2022-08-29T00:00:00Z", "publisher": {"@type": "org:Organization", "name": "U.S. Geological Survey"}, "spatial": "-103.8750, 40.25000, -103.7500, 40.37500", "theme": ["geospatial"], "title": "Data release for the geologic map of the Fort Morgan 7.5' quadrangle, Morgan County, Colorado"}