Metadata: Identification_Information: Citation: Citation_Information: Originator: Stephen D. Belew Originator: VeeAnn A. Cross Publication_Date: 2003 Title: Surface Representing the Floor of Lake Mead and the surrounding area: UTM Projection 10m cellsize Geospatial_Data_Presentation_Form: raster digital data Series_Information: Series_Name: Open-File Report Issue_Identification: 03-320 Publication_Information: Publication_Place: Woods Hole Coastal and Marine Science Center, Woods Hole, MA Publisher: U.S. Geological Survey, Coastal and Marine Geology Program Online_Linkage: https://doi.org/10.3133/ofr03320 Online_Linkage: https://pubs.usgs.gov/of/2003/of03-320/htmldocs/datacatalog.htm Online_Linkage: https://pubs.usgs.gov/of/2003/of03-320/data/surfaces/utm11/presentday.zip Larger_Work_Citation: Citation_Information: Originator: David C. Twichell Originator: VeeAnn A. Cross Originator: Stephen D. Belew Publication_Date: 2003 Title: Mapping the floor of Lake Mead (Nevada and Arizona): Preliminary discussion and GIS data release Edition: 1.0 Series_Information: Series_Name: Open-File Report Issue_Identification: 03-320 Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Online_Linkage: https://pubs.usgs.gov/of/2003/of03-320/ Description: Abstract: Lake Mead is a large interstate reservoir located in the Mojave Desert of southeastern Nevada and northwestern Arizona. It was impounded in 1935 by the construction of Hoover Dam and is one of a series of multi-purpose reservoirs on the Colorado River. The lake extends 183 km from the mouth of the Grand Canyon to Black Canyon, the site of Hoover Dam, and provides water for residential, commercial, industrial, recreational, and other non-agricultural users in communities across the southwestern United States. Extensive research has been conducted on Lake Mead, but a majority of the studies have involved determining levels of anthropogenic contaminants such as synthetic organic compounds, heavy metals and dissolved ions, furans/dioxins, and nutrient loading in lake water, sediment, and biota (Preissler, et al., 1998; Bevans et al, 1996; Bevans et al., 1998; Covay and Leiker, 1998; LaBounty and Horn, 1997; Paulson, 1981). By contrast, little work has focused on the sediments in the lake and the processes of deposition (Gould, 1951). To address these questions, sidescan-sonar imagery and high-resolution seismic-reflection profiles were collected throughout Lake Mead by the USGS in cooperation with researchers from University of Nevada Las Vegas (UNLV). These data allow a detailed mapping of the surficial geology and the distribution and thickness of sediment that has accumulated in the lake since the completion of Hoover Dam. Results indicate that the accumulation of post-impoundment sediment is primarily restricted to former river and stream beds that are now submerged below the lake while the margins of the lake appear to be devoid of post-impoundment sediment. The sediment cover along the original Colorado River bed is continuous and is typically greater than 10 m thick through much of its length. Sediment thickness in some areas exceeds 35 m while the smaller tributary valleys typically are filled with less than 4 m of sediment. Away from the river beds that are now covered with post-impoundment sediment, pre-impoundment alluvial deposits and rock outcrops are still exposed on the lake floor. Purpose: This GIS (ESRI) grid represents the integration swath bathymetry, on land DEM, and underwater surface derived from countour maps generated pre-impoundment. Supplemental_Information: Questions regarding the swath bathymetry portion of this dataset should be directed to Steve Belew, while questions regarding the remainder of the dataset and the integration should be directed to VeeAnn Cross. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 1930 Ending_Date: 200111 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -114.996607 East_Bounding_Coordinate: -114.003332 North_Bounding_Coordinate: 36.747197 South_Bounding_Coordinate: 35.758068 Keywords: Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:edfee35a-756c-45b2-bdf6-ed1a0f69f8c0 Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: ArcView Theme_Keyword: bathymetry Theme_Keyword: CMGP Theme_Keyword: Coastal and Marine Geology Program Theme_Keyword: DEM Theme_Keyword: digital elevation model Theme_Keyword: grid Theme_Keyword: images Theme_Keyword: lake Theme_Keyword: mosaic Theme_Keyword: OFR03-320 Theme_Keyword: Open-File Report Theme_Keyword: reservoir Theme_Keyword: U.S. Geological Survey Theme_Keyword: USGS Theme_Keyword: Woods Hole Field Center Theme_Keyword: Bureau of Reclamation Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: inlandWaters Theme_Keyword: geoscientificInformation Theme_Keyword: imageryBaseMapsEarthCover Theme_Keyword: elevation Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: topography Theme_Keyword: lakebed characteristics Theme_Keyword: bathymetry Place: Place_Keyword_Thesaurus: None Place_Keyword: Arizona Place_Keyword: Black Canyon Place_Keyword: Boulder Basin Place_Keyword: Colorado River Place_Keyword: Gregg Basin Place_Keyword: Hoover Dam Place_Keyword: Iceberg Canyon Place_Keyword: Lake Mead Place_Keyword: Las Vegas Place_Keyword: Las Vegas Bay Place_Keyword: Las Vegas Wash Place_Keyword: Mohave Desert Place_Keyword: Nevada Place_Keyword: Overton Arm Place_Keyword: United States Place_Keyword: Virgin Basin Place_Keyword: North America Access_Constraints: NONE Use_Constraints: The U.S. Geological Survey and Bureau of Reclamation must be referenced as the originator of the dataset in any future products or research derived from these data. Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Steve Belew Contact_Organization: Bureau of Reclamation Contact_Position: GIS Specialist Contact_Address: Address_Type: mailing address Address: P.O. Box 61470 City: Boulder City State_or_Province: NV Postal_Code: 89006-1470 Country: sbelew@usbr.gov Contact_Voice_Telephone: (702) 293-8150 Native_Data_Set_Environment: Microsoft Windows 2000 Version 5.0 (Build 2195) Service Pack 4; ESRI ArcCatalog 8.2.0.700 Cross_Reference: Citation_Information: Originator: H.E. Bevans Originator: S.L. Goodbred Originator: J.F. Miesner Originator: S.A. Watkins Originator: T.S. Gross Originator: N.D. Denslow Originator: T. Choeb Publication_Date: 1996 Title: Synthetic organic compounds and carp endrocrinology and histology, Las Vegas Wash and Las Vegas and Callville bays of Lake Mead Nevada Series_Information: Series_Name: Water-Resources Investigations Issue_Identification: 96-4266 Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Cross_Reference: Citation_Information: Originator: H.E. Bevans Originator: M.S. Lico Originator: S.J. Lawrence Publication_Date: 1998 Title: Water quality in the Las Vegas Valley area and the Carson and Truckee River basins, Nevada and California, 1992-1996 Series_Information: Series_Name: Circular Issue_Identification: 1170 Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Cross_Reference: Citation_Information: Originator: K.J. Couvay Originator: T.J. Leiker Publication_Date: 1998 Title: Synthetic organic compounds in water and bottom sediment from streams, detention basins, and sewage-treatment plant outfalls in Las Vegas Valley, Nevada, 1997 Series_Information: Series_Name: Open-File Report Issue_Identification: 98-633 Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Cross_Reference: Citation_Information: Originator: H.R. Gould Publication_Date: 1951 Title: Some quantitative aspects of Lake Mead turbidity currents Series_Information: Series_Name: SEPM Special Publication Issue_Identification: No. 2 Publication_Information: Publication_Place: Tulsa, OK Publisher: Society of Economic Paleontologists and Mineralogists Cross_Reference: Citation_Information: Originator: J.F. LaBounty Originator: M.J. Horn Publication_Date: 1997 Title: The influence of drainage from the Las Vegas Valley on the limnology of Boulder Basin, Lake Mead, Arizona-Nevada Series_Information: Series_Name: Journal of Lake and Reservoir Management Issue_Identification: v. 13 Cross_Reference: Citation_Information: Originator: L.J. Paulson Publication_Date: 1981 Title: Nutrient management with hydroelectric dams on the Colorado River Series_Information: Series_Name: Technical Report Issue_Identification: #8 Publication_Information: Publication_Place: Department of Biological Sciences, University of Nevada, Las Vegas, Nevada Publisher: Lake Mead Limnological Research Center Cross_Reference: Citation_Information: Originator: A.M. Preissler Originator: G.A. Roach Originator: K.A. Thomas Originator: J.W. Wilson Publication_Date: 1998 Title: Water resources data, Nevada, water year 1998 Series_Information: Series_Name: Water Resources Data Nevada Issue_Identification: NV-98-1 Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: The nature of combining three different datasets tends to reduce the overall accuracy. Therefore a nominal accuracy of 50-100m is assigned to this dataset. Logical_Consistency_Report: This surface represents the integration of three datasets. One is the swath bathymetry data collected in Lake Mead in November of 2001. The second dataset is the on land DEM acquired from the NED (National Elevation Dataset) project. And the final dataset is the surface generated from pre-impoundment elevation contours as digitized from DRG's of Lake Mead (digital raster graphics). Due to the nature of combining these three different datasets, discrepancies are evident at the bounds of each of the datasets. Completeness_Report: This dataset is complete. Lineage: Process_Step: Process_Description: Three sets of data were acquired. The DEM from the area surrounding Lake Mead was acquired from NED (National Elevation Dataset) in 1998. This data was available as 30m/pixel. The swath bathymetry data was collected in Lake Mead during the fall of 2001. Bureau of Reclamation had this data at a very high resolution. The area covered by this surveying is effectively limited to the areas of post-impoundment sediment. The underwater contours available from the DRG's (digital raster graphics) were digitized. These contours were then used to create an underwater surface using the ESRI topogrid command available in Arc/Info. This surface was created with a 10 m/pixel resolution. Process_Date: unknown Process_Step: Process_Description: The lake bounds shapefile was used to clip the DEM dataset such that all values falling within the lake bounds were turned to NODATA values. Process_Date: unknown Process_Step: Process_Description: The lake bounds shapefile was used to clip the topogrid dataset such that all values falling outside the lake bounds were turned to NODATA values. Process_Date: unknown Process_Step: Process_Description: The high-resolution bathymetry data was resampled to a 10 m cellsize using bilinear interpolation. Process_Date: unknown Process_Step: Process_Description: The swath bathymetry grid was merged with the topogrid surface such that where swath bathymetry data was available, the topogrid surface was overwritten. This provided the present day lakefloor of Lake Mead. Process_Date: unknown Process_Step: Process_Description: The on land DEM was resampled to a 10 m cellsize grid (super sampling). Process_Date: unknown Process_Step: Process_Description: This supersampled on land DEM was then combined with the lake floor surface. Process_Date: unknown Process_Step: Process_Description: The resulting surface then underwent several repetitions of a 4x4 focal mean filtering to remove and null data values and to smooth the transition from one dataset to the next. Process_Date: unknown Process_Step: Process_Description: Edits to the metadata were made to fix any errors that MP v 2.9.36 flagged. This is necessary to enable the metadata to be successfully harvested for various data catalogs. In some cases, this meant adding text "Information unavailable" or "Information unavailable from original metadata" for those required fields that were left blank. Other minor edits were probably performed (title, publisher, publication place, etc.). Added online links to the data in the identification section and the distribution section and also a link to the larger work citation. Added ISO 19115 Topic Category keywords. The standard order process section in the Distribution section was incomplete and had to be modified to meet the standard. The metadata date (but not the metadata creator) was edited to reflect the date of these changes. The metadata available from a harvester may supersede metadata bundled within a download file. Compare the metadata dates to determine which metadata file is most recent. Process_Date: 20170330 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: VeeAnn A. Cross Contact_Position: Marine Geologist Contact_Address: Address_Type: Mailing and Physical Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Contact_Voice_Telephone: 508-548-8700 x2251 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: vatnipp@usgs.gov Process_Step: Process_Description: USGS Thesaurus keywords added to the keyword section. Process_Date: 20180720 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: VeeAnn A. Cross Contact_Position: Marine Geologist Contact_Address: Address_Type: Mailing and Physical Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Contact_Voice_Telephone: 508-548-8700 x2251 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: vatnipp@usgs.gov Process_Step: Process_Description: Crossref DOI link was added as the first link in the metadata. Process_Date: 20191118 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: VeeAnn A. Cross Contact_Position: Marine Geologist Contact_Address: Address_Type: Mailing and Physical Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Contact_Voice_Telephone: 508-548-8700 x2251 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: vatnipp@usgs.gov Process_Step: Process_Description: Added keywords section with USGS persistent identifier as theme keyword. Process_Date: 20200908 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: VeeAnn A. Cross Contact_Position: Marine Geologist Contact_Address: Address_Type: Mailing and Physical Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Contact_Voice_Telephone: 508-548-8700 x2251 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: vatnipp@usgs.gov Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Raster Raster_Object_Information: Raster_Object_Type: Grid Cell Row_Count: 10759 Column_Count: 8654 Vertical_Count: 1 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Grid_Coordinate_System: Grid_Coordinate_System_Name: Universal Transverse Mercator Universal_Transverse_Mercator: UTM_Zone_Number: 11 Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.999600 Longitude_of_Central_Meridian: -117.000000 Latitude_of_Projection_Origin: 0.000000 False_Easting: 500000.000000 False_Northing: 0.000000 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: row and column Coordinate_Representation: Abscissa_Resolution: 10.000000 Ordinate_Resolution: 10.000000 Planar_Distance_Units: meters Geodetic_Model: Horizontal_Datum_Name: North American Datum of 1983 Ellipsoid_Name: Geodetic Reference System 80 Semi-major_Axis: 6378137.000000 Denominator_of_Flattening_Ratio: 298.257222 Distribution_Information: Distributor: Contact_Information: Contact_Person_Primary: Contact_Person: VeeAnn A. Cross Contact_Organization: U.S. Geological Survey Contact_Position: Marine Geologist Contact_Address: Address_Type: mailing and physical address Address: 384 Woods Hole Rd. City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Contact_Voice_Telephone: (508) 548-8700 x2251 Contact_Facsimile_Telephone: (508) 457-2310 Contact_Electronic_Mail_Address: vatnipp@usgs.gov Resource_Description: Downloadable Data Distribution_Liability: These data were prepared by an agency of the United States Government. Neither the United States government nor any agency thereof, nor any of their employees, make any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed in this report, or represents that its use would not infringe privately owned rights. Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States government or any agency thereof. Any views and opinions of authors expressed herein do not necessarily state or reflect those of the United States government or any agency thereof. Although all data published in this report have been used by the USGS, no warranty, expressed or implied, is made by the USGS as to the accuracy of the data and related materials and/or the functioning of the software. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of this data, software, or related materials. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: AAIGrid Format_Information_Content: Zip file containing the Esri ascii grid. Transfer_Size: 356.792 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://pubs.usgs.gov/of/2003/of03-320/data/surfaces/utm11/presentday.zip Fees: none Metadata_Reference_Information: Metadata_Date: 20240318 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: VeeAnn A. Cross Contact_Organization: U.S. Geological Survey Contact_Position: Marine Geologist Contact_Address: Address_Type: mailing and physical address Address: 384 Woods Hole Rd. City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Contact_Voice_Telephone: (508) 548-8700 x2251 Contact_Facsimile_Telephone: (508) 457-2310 Contact_Electronic_Mail_Address: whsc_data_contact@usgs.gov Contact_Instructions: The metadata contact email address is a generic address in the event the person is no longer with USGS. (updated on 20240318) Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Time_Convention: local time