Metadata: Identification_Information: Citation: Citation_Information: Originator: VeeAnn A. Cross Originator: David C. Twichell Publication_Date: Unpublished material Title: SEG-Y format of chirp seismic-reflection profiles collected in Lake Mead in 1999 Publication_Information: Publication_Place: Woods Hole Coastal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://cmgds.marine.usgs.gov/fan_info.php?fan=1999-014-FA 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: The seismic data were collected to determine sediment thickness in Lake Mead. These data, along with sidescan-sonar data can help determine the sediment distribution in Lake Mead. Additionally, these data along with piston core data can enable the mapping of various sediment facies distribution in the lake. Supplemental_Information: For more information on the seismic surveys see https://cmgds.marine.usgs.gov/fan_info.php?fan=1999-014-FA. These data are also available via GeoMapApp (http://www.geomapapp.org/) and Virtual Ocean ( http://www.virtualocean.org/) earth science exploration and visualization applications. The JPEG format of these data (along with other data associated with this field activity) were released through the Open-File Report 2003-320 (https://pubs.usgs.gov/of/2003/of03-320/). See the cross-reference for full citation information. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 19990514 Ending_Date: 19990525 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -114.857591 East_Bounding_Coordinate: -114.589473 North_Bounding_Coordinate: 36.145382 South_Bounding_Coordinate: 36.018801 Keywords: Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:f8e5f393-fd99-4a4d-9934-dcfd4b4fc63e Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: seismic Theme_Keyword: SEG-Y Theme_Keyword: chirp Theme_Keyword: images Theme_Keyword: U.S. Geological Survey Theme_Keyword: USGS Theme_Keyword: Coastal and Marine Geology Program Theme_Keyword: CMGP Theme_Keyword: Woods Hole Field Center Theme_Keyword: Open-File Report Theme_Keyword: OFR03-320 Theme_Keyword: cruise serial number 99014 Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: inlandWaters Theme_Keyword: geoscientificInformation Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: sub-bottom profiling Theme_Keyword: geophysics Place: Place_Keyword_Thesaurus: None Place_Keyword: Lake Mead Place_Keyword: Nevada Place_Keyword: United States Place_Keyword: Las Vegas Place_Keyword: Hoover Dam Place_Keyword: Colorado River Place_Keyword: Mojave Desert Place_Keyword: Grand Canyon Place_Keyword: Black Canyon Place_Keyword: Arizona Place_Keyword: North America Access_Constraints: None Use_Constraints: The U.S. Geological Survey 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: 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 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: V.A. Cross Originator: D.C. Twichell Publication_Date: 2003 Title: Archive of Seismic-Reflection Data Collected During USGS Cruise Lake Mead 99014 in Lake Mead - Nevada and Arizona, 14-25May, 1999 Series_Information: Series_Name: Open-File Report Issue_Identification: 03-003 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 Cross_Reference: 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/ Data_Quality_Information: Logical_Consistency_Report: Information unavailable from original metadata. Completeness_Report: These files represent images of all the seismic-reflection data collected in Lake Mead in 1999 by the USGS. Lineage: Process_Step: Process_Description: The seismic data collected in 1999 was chirp seismic data. These data were collected as part of the SIS-1000 system. The SEG-Y data first had to be separated from the raw datafile. This was accomplished with an in-house software package called "qmipstosegy". Process_Date: unknown Process_Step: Process_Description: The SEG-Y data were then loaded into Landmark software and interpreted. Process_Date: unknown Process_Step: Process_Description: CGM images were created of each seismic profile - with the interpretation and without the interpretation. Therefore 2 images for each profile. The interpreted post-impoundment surface is the blue line, while the interpreted pre-impoundment surface is the red line. Process_Date: unknown Process_Step: Process_Description: These CGM images were converted to JPEGs using Larson software. Process_Date: unknown Process_Step: Process_Description: These jpegs were then downsampled and converted to a GIF format using djpeg on a UNIX system. Process_Date: unknown Process_Step: Process_Description: These GIFS were then converted back to JPEGs using the convert command on a UNIX system. 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. Added the standard order process section in the Distribution section. 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: 20170404 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: This metadata record was modified from one describing JPEG images to reflect the SEG-Y version of the same data (Open-File Report 2003-320, https://pubs.usgs.gov/of/2003/of03-320/). Changes were made to the Citation and Distribution_Information. Process_Date: 20171121 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: 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 Entity_and_Attribute_Information: Overview_Description: Entity_and_Attribute_Overview: These images are intended only as previews of the seismic-reflection data. In each image, the x-axis represents shot point, the y-axis is two-way travel time in milliseconds. The scale bar along the bottom of the image is inaccurate due to a bug in the digital processing software and therefore should be ignored. 99seisinterp.zip contains JPEG images of the 1999 interpreted chirp seismic-reflection profiles. 99seisraw.zip contains JPEG images of the 1999 uninterpreted chirp seismic-reflection profiles. The blue line on the images represents the interpreted post-impoundment surface while the red line represents the interpreted pre-impoundment surface. Entity_and_Attribute_Detail_Citation: U.S. Geological Survey 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: SEG-Y Format_Information_Content: Link is to a folder containing SEG-Y files. Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://cmgds.marine.usgs.gov/data/1999_014_FA/ Access_Instructions: The online link gives access to the folder containing the individual SEG-Y files. Fees: none Technical_Prerequisites: These data require software that can read SEG-Y data. Metadata_Reference_Information: Metadata_Date: 20200908 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: vatnipp@usgs.gov Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Time_Convention: local time Metadata_Access_Constraints: none Metadata_Use_Constraints: none