Sidescan-sonar Tracklines in the Geographic Coordinate System - Lake Mead 2000

Metadata:

• Identification_Information
• Data_Quality_Information
• Spatial_Data_Organization_Information
• Spatial_Reference_Information
• Entity_and_Attribute_Information
• Distribution_Information
• Metadata_Reference_Information

Identification_Information:

Citation:

Citation_Information:

Originator: David C. Twichell

Originator: VeeAnn A. Cross

Publication_Date: 2003

Title:

Sidescan-sonar Tracklines in the Geographic Coordinate System - Lake Mead 2000

Geospatial_Data_Presentation_Form: vector digital data

Online_Linkage:

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: Woods Hole Field Center, Woods Hole, MA

Publisher: U.S. Geological Survey

Description:

Abstract:

A one-week geophysical survey was conducted in the Las Vegas Bay part of Lake Mead during June 1-6, 2000 to acoustically map the surficial sediments and shallow subsurface geology of this part of the lake. The study was done by researchers from the U.S. Geological Survey, Coastal and Marine Geology Program in Woods Hole, MA and the University of Nevada at Las Vegas. The objective was to map the distribution, volume and acoustic character of sediment that has accumulated on the floor of this part of the lake. The need for systematic mapping of this part of the lake's floor is because pollutants associated with surface and groundwater enter the lake through Las Vegas Wash at the head of Las Vegas Bay. Some of the pollutants transported to the lake by this runoff are deposited with the sediments on the lake floor. Understanding the distribution of sediments in the lake is needed to establish an effective monitoring program. The study built upon a geophysical survey conducted by the USGS and UNLV in 1999 that covered the deeper water parts of Las Vegas Bay and Boulder Basin. This year's survey focussed on the shallow water parts of the head of Las Vegas Bay with particular attention being directed at Las Vegas, Gypsum and Government Washes. Of these three Washes, the most effort was put into surveying Las Vegas Wash. This survey was conducted with an Edgetech DF-1000 sidescan sonar, a Knudsen high-resolution chirp subbottom profiling system, a Garmin fathometer, and P-Code GPS navigation. All data were logged digitally.

Purpose:

This ArcView shapefile defines the tracklines along which sidescan sonar data was collected.

Time_Period_of_Content:

Time_Period_Information:

Range_of_Dates/Times:

Beginning_Date: 20000601

Ending_Date: 20000606

Currentness_Reference: ground condition

Status:

Progress: Complete

Maintenance_and_Update_Frequency: None planned

Spatial_Domain:

Bounding_Coordinates:

West_Bounding_Coordinate: -114.874450

East_Bounding_Coordinate: -114.808870

North_Bounding_Coordinate: 36.135890

South_Bounding_Coordinate: 36.114000

Keywords:

Theme:

Theme_Keyword_Thesaurus: General

Theme_Keyword: sidescan sonar

Theme_Keyword: trackline

Theme_Keyword: navigation

Theme_Keyword: reservoir

Theme_Keyword: U.S. Geological Survey

Theme_Keyword: USGS

Theme_Keyword: Coastal and Marine Geology Program

Theme_Keyword: CMGP

Theme_Keyword: Open-File Report

Theme_Keyword: OFR03-320

Theme_Keyword: cruise serial number 00027

Place:

Place_Keyword_Thesaurus: General

Place_Keyword: Las Vegas

Place_Keyword: Lake Mead

Place_Keyword: Nevada

Place_Keyword: Las Vegas Bay

Place_Keyword: Las Vegas Wash

Place_Keyword: Boulder Basin

Place_Keyword: United States

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: David C. Twichell

Contact_Organization: U.S. Geological Survey

Contact_Position: Oceanographer

Contact_Address:

Address_Type: mailing and physical address

Address: 384 Woods Hole Rd.

City: Woods Hole

State_or_Province: MA

Postal_Code: 02543

Contact_Voice_Telephone: 508-548-8700 x2266

Contact_Facsimile_Telephone: 508-457-2310

Contact_Electronic_Mail_Address: dtwichell@usgs.gov

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:

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:

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:

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 00027 in Lake Mead - Nevada, 1-6 June, 2000

Series_Information:

Series_Name: Open-File Report

Issue_Identification: 03-004

Publication_Information:

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:

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:

Publisher: U.S. Geological Survey

Data_Quality_Information:

Logical_Consistency_Report:

These lines represent the lines along which sidescan-sonar image data were collected.

Completeness_Report: Complete.

Positional_Accuracy:

Horizontal_Positional_Accuracy:

Quantitative_Horizontal_Positional_Accuracy_Assessment:

Horizontal_Positional_Accuracy_Value: 10-20m

Horizontal_Positional_Accuracy_Explanation:

The navigation data were collected with a P-CODE GPS with an assumed accurace of +/- 10 m. Additional error is encountered due to the offset between the sidescan-sonar towfish and the navigation antenna. Furthermore, the navigation was downsampled so that only the most accurate navigation positions are the vertex points of the line.

Lineage:

Process_Step:

Process_Description:

Navigation was acquired by a Hypack navigation system and stored with the Edgetech sidescan sonar data on a QMIPS computer data acquisition system. A unique navigation point was sent to the acquisition system approximately every 10 seconds. Upon extracting the sidescan-sonar data from the acquisition system, the navigation was downsampled to 1 minute intervals.

Process_Step:

Process_Description:

This 1 minute navigation was then reviewed for errors and sometimes further downsampled to enable the swath of sidescan-sonar imagery to have a smooth track.

Process_Step:

Process_Description:

This navigation for each line of sidescan data was then combined with all the other lines into an Arc/Info ungenerate format for import into ArcView.

Process_Step:

Process_Description:

Within ArcView, additional attribute information for each line was added.

Spatial_Data_Organization_Information:

Direct_Spatial_Reference_Method: Vector

Point_and_Vector_Object_Information:

SDTS_Terms_Description:

SDTS_Point_and_Vector_Object_Type: String

Point_and_Vector_Object_Count: 26

Spatial_Reference_Information:

Horizontal_Coordinate_System_Definition:

Geographic:

Latitude_Resolution: 0.000000

Longitude_Resolution: 0.000000

Geographic_Coordinate_Units: Decimal degrees

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

Entity_and_Attribute_Information:

Detailed_Description:

Entity_Type:

Entity_Type_Label: ssnav_00.dbf

Entity_Type_Definition: ArcView shapefile attribute table

Entity_Type_Definition_Source: ESRI

Attribute:

Attribute_Label: FID

Attribute_Definition: Internal feature number.

Attribute_Definition_Source: ESRI

Attribute_Domain_Values:

Unrepresentable_Domain:

Sequential unique whole numbers that are automatically generated.

Attribute:

Attribute_Label: Shape

Attribute_Definition: Feature geometry.

Attribute_Definition_Source: ESRI

Attribute_Domain_Values:

Unrepresentable_Domain: Coordinates defining the features.

Attribute:

Attribute_Label: LINENUM

Attribute_Definition:

A numeric value indicating a line number. Test files collected during the cruise and subsequently used for interpretations are given line numbers in the range of 501-503. This is to differentiate test file 1 from line 1.

Attribute_Definition_Source: VeeAnn A. Cross

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 1

Range_Domain_Maximum: 503

Attribute:

Attribute_Label: FILENAME

Attribute_Definition:

Prefix of the filename assigned to each line of sidescan-sonar data collected.

Attribute_Definition_Source: Kenneth F. Parolski

Attribute_Domain_Values:

Unrepresentable_Domain: Character data set

Attribute:

Attribute_Label: SWATH

Attribute_Definition:

The total swath that the sidescan-sonar imagery covers (in meters).

Attribute_Definition_Source: VeeAnn A. Cross

Attribute_Domain_Values:

Enumerated_Domain:

Enumerated_Domain_Value: 200m

Enumerated_Domain_Value_Definition: 200 meters

Attribute:

Attribute_Label: lengthm

Attribute_Definition: The length of each line segment in meters.

Attribute_Definition_Source: Software computed.

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 529

Range_Domain_Maximum: 2243

Distribution_Information:

Distributor:

Contact_Information:

Contact_Person_Primary:

Contact_Person: David C. Twichell

Contact_Organization: U.S. Geological Survey

Contact_Position: Oceanographer

Contact_Address:

Address_Type: mailing and physical address

Address: 384 Woods Hole Rd.

City: Woods Hole

State_or_Province: MA

Postal_Code: 02543

Contact_Voice_Telephone: 508-548-8700 x2266

Contact_Facsimile_Telephone: 508-457-2310

Contact_Electronic_Mail_Address: dtwichell@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:

Transfer_Size: 0.028

Metadata_Reference_Information:

Metadata_Date: 20031006

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:

REQUIRED: The mailing and/or physical address for the organization or individual.

City: REQUIRED: The city of the address.

State_or_Province: REQUIRED: The state or province of the address.

Postal_Code: REQUIRED: The ZIP or other postal code of the address.

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_Extensions:

Online_Linkage: <http://www.esri.com/metadata/esriprof80.html>

Profile_Name: ESRI Metadata Profile