Multibeam mapping of Lake Tahoe, California-Nevada from Field Activity: L-1-98-LT

Frequently-anticipated questions:

• What does this data set describe?
  1. How should this data set be cited?
  2. What geographic area does the data set cover?
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
  5. What is the general form of this data set?
  6. How does the data set represent geographic features?
  7. How does the data set describe geographic features?
• Who produced the data set?
  1. Who are the originators of the data set?
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
• Why was the data set created?
• How was the data set created?
  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
  3. What similar or related data should the user be aware of?
• How reliable are the data; what problems remain in the data set?
  1. How well have the observations been checked?
  2. How accurate are the geographic locations?
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
  5. How consistent are the relationships among the data, including topology?
• How can someone get a copy of the data set?
  1. Are there legal restrictions on access or use of the data?
  2. Who distributes the data?
  3. What's the catalog number I need to order this data set?
  4. What legal disclaimers am I supposed to read?
  5. How can I download or order the data?
• Who wrote the metadata?

Title:

Multibeam mapping of Lake Tahoe, California-Nevada from Field Activity: L-1-98-LT

Abstract:

ArcInfo export format bathymetry data generated from the 1998 multibeam sonar survey of Lake Tahoe, California-Nevada.

Supplemental_Information:

Information for USGS Coastal and Marine Geology related activities are online at <http://walrus.wr.usgs.gov/infobank/i/i198lt/html/i-1-98-lt.meta.html>

1. How should this data set be cited?

   United States Geological Survey, Coastal and Marine Geology (CMG), Chief, 2001, Multibeam mapping of Lake Tahoe, California-Nevada from Field Activity: L-1-98-LT.

   Online Links:

   • none

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -120.16874416

   East_Bounding_Coordinate: -119.92586202

   North_Bounding_Coordinate: 39.24651281

   South_Bounding_Coordinate: 38.94493068

3. What does it look like?

4. Does the data set describe conditions during a particular time period?

   Beginning_Date: 02-Aug-1998

   Ending_Date: 17-Aug-1998

   Currentness_Reference: ground condition

5. What is the general form of this data set?

   Geospatial_Data_Presentation_Form: ArcInfo export

6. How does the data set represent geographic features?
   1. How are geographic features stored in the data set?

      This is a Raster data set. It contains the following raster data types:

      • Dimensions 3416 x 1992, type Grid Cell

   2. What coordinate system is used to represent geographic features?

      Grid_Coordinate_System_Name: Universal Transverse Mercator

      Universal_Transverse_Mercator:

      UTM_Zone_Number: 10

      Transverse_Mercator:

      Scale_Factor_at_Central_Meridian: 0.9996

      Longitude_of_Central_Meridian: -123.00000

      Latitude_of_Projection_Origin: 0.00000

      False_Easting: 0.00

      False_Northing: 0.00

      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 10.0
      Ordinates (y-coordinates) are specified to the nearest 10.0
      Planar coordinates are specified in Meters

      The horizontal datum used is WGS84.
      The ellipsoid used is WGS84.
      The semi-major axis of the ellipsoid used is 6378137.00 meters.
      The flattening of the ellipsoid used is 1/0.003352811.
      

7. How does the data set describe geographic features?

   Entity_and_Attribute_Overview:

   TAHOEGRD is an ArcInfo GRID with the following attributes:

   Data Type: Floating

   BOUNDARY (UTM meters) Xmin = 745374.500 Xmax = 765294.500 Ymin = 4314478.000 Ymax = 4348638.000

   STATISTICS (grid cell values, elevation in meters) Minimum Value = 1400.017 Maximum Value = 1898.999 Mean = 1566.823 Standard Deviation = 161.000

   Entity_and_Attribute_Detail_Citation: none

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • United States Geological Survey (USGS),

2. Who also contributed to the data set?

3. To whom should users address questions about the data?

   James V. Gardner
   United States Geological Survey (USGS)
   Geologist
   USGS, MailStop 999, 345 Middlefield Road
   Menlo Park, CA 94025-3561
   USA
   

   (650) 329-5469 (voice)
   (650) 329-5411 (FAX)
   jvgardner@usgs.gov
   

These data are intended for science researchers, students, policy makers, and the general public. The data can be used with geographic information systems (GIS) or other software to display bathymetry data of Lake Tahoe CA-NV

1. From what previous works were the data drawn?

2. How were the data generated, processed, and modified?

   Date: 15-Feb-2000 (process 1 of 1)

   The bathymetry data were collected along a continuous swath perpendicular to the direction of the ship using a Kongsberg Simrad EM1000 multibeam sonar system. The data are cleaned of bad navigation and depth readings. The depth readings are gridded into a common grid. The gridded data are converted to ArcInfo GRID format using ArcInfo's ASCIIGRID command.

   Person who carried out this activity:
   

   James V. Gardner
   United States Geological Survey (USGS)
   Geologist
   USGS, MailStop 999, 345 Middlefield Road
   Menlo Park, CA 94025-3561
   USA
   

   (650) 329-5469 (voice)
   (650) 329-5411 (FAX)
   jvgardner@usgs.gov
   

3. What similar or related data should the user be aware of?

1. How well have the observations been checked?

   Not applicable for raster data.

2. How accurate are the geographic locations?

   0.5 meters

3. How accurate are the heights or depths?

   0.5 percent of the water depth

4. Where are the gaps in the data? What is missing?

   Complete

5. How consistent are the relationships among the observations, including topology?

   Unspecified

Are there legal restrictions on access or use of the data?

Access_Constraints: None

Use_Constraints:

Please recognize the U.S. Geological Survey (USGS) as the source of this information. USGS-authored or produced data and information are in the public domain.

1. Who distributes the data set? (Distributor 1 of 1)

   United States Geological Survey (USGS)
   c/o James V. Gardner
   Geologist
   USGS, Mailstop, 345 Middlefield Road
   Menlo Park, CA 94025
   USA
   

   (650)329-5469 (voice)
   (650) 329-5411 (FAX)
   jvgardner@usgs.gov
   

2. What's the catalog number I need to order this data set?

   L-1-98-LT data set

3. What legal disclaimers am I supposed to read?

   These data not intended for navigational purposes.

   Although these data have been used by the U.S. Geological Survey, U.S. Department of the Interior, these data and information are provided with the understanding that they are not guaranteed to be usable, timely, accurate, or complete. Users are cautioned to consider carefully the provisional nature of these data and information before using them for decisions that concern personal or public safety or the conduct of business that involves substantial monetary or operational consequences. Conclusions drawn from, or actions undertaken on the basis of, such data and information are the sole responsibility of the user.

   Neither the U.S. Government nor any agency thereof, nor any of their employees, contractors, or subcontractors, make any warranty, express or implied, nor assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any data, software, information, apparatus, product, or process disclosed, nor represent that its use would not infringe on privately owned rights.

   Trade, firm, or product names and other references to non-USGS products and services are provided for information only and do not constitute endorsement or warranty, express or implied, by the USGS, US Department of the Interior, or U.S. Government, as to their suitability, content, usefulness, functioning, completeness, or accuracy.

4. How can I download or order the data?
   • Availability in digital form:

     Data format:	ARCE (version 8.0.2) Size: 17 megabytes
     Network links:	<http://tahoe.usgs.gov/>

   • Cost to order the data: None

Dates:

Last modified: 09-Aug-2001

Metadata author:

Pete Dartnell
United States Geological Survey (USGS)
Physical Scientist
USGS, MailStop 999, 345 Middlefield Road
Menlo Park, CA 94025-3561
USA

(650) 329-5460 (voice)
(650) 329-5411 (FAX)
pdartnell@usgs.gov

Metadata standard:

Content Standard for Digital Geospatial Metadata ("CSDGM version 2") (FGDC-STD-001-1998)