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Bathymetry and Acoustic Backscatter of Crater Lake, Oregon from Field Activity: S-1-00-OR

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?

What does this data set describe?

1. How should this data set be cited?

   Gardner, James V. , and Dartnell, Peter, 2001, Bathymetry and Acoustic Backscatter of Crater Lake, Oregon from Field Activity: S-1-00-OR:.

   This is part of the following larger work.

   Gardner, James V. , and Dartnell, Peter, 2001, 2000 Multibeam Sonar Survey of Crater Lake, Oregon: Data, GIS, Images, and Movies: U.S. Geological Survey Digital Data Series 72.

   Online Links:

   • <http://pubs.usgs.gov/dds/dds-72/>

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -122.16555054

   East_Bounding_Coordinate: -122.04983558

   North_Bounding_Coordinate: 42.97851439

   South_Bounding_Coordinate: 42.90490823

3. What does it look like?

   <http://pubs.usgs.gov/dds/dds-72/site/images/cl-persp.img/cl-map.gif> (GIF)

   Map view of Crater Lake, Oregon. Colored region is the lake floor whereas the gray region is the surrounding land. The distance across the width if the lake is approximately 9 kilometers (5.6 miles). The reds and yellows show the shallower depths of the lake, whereas the greens and blues show the deeper depths.

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

   Beginning_Date: 28-Jul-2000

   Ending_Date: 03-Aug-2000

   Currentness_Reference: ground condition

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

   Geospatial_Data_Presentation_Form: XYZ ASCII

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

      This is a Point data set. It contains the following vector data types (SDTS terminology):

      • Point (13,246,103)
      It contains the following raster data types:
      • Dimensions 4137 x 4677, 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 2.0
      Ordinates (y-coordinates) are specified to the nearest 2.0
      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:

   Coordinates in the XYZ ASCII file are given in decimal degrees. Bathymetry is given in meters. Backscatter is an arbitrary scale ranging from 26 to 254.
   Sample of bathymetry XYZ ASCII file

   Longitude, Latitude, Elevation
   -122.11496,42.96909,1514.068
   -122.11494,42.96909,1514.674
   -122.11492,42.96909,1515.272
   -122.11490,42.96909,1515.862
   -122.11487,42.96909,1516.448
   -122.11485,42.96909,1517.026
   -122.11483,42.96909,1517.591
   -122.11481,42.96909,1518.141
   -122.11479,42.96909,1518.691
   

   Sample of Backscatter XYZ ASCII file

    Longitude, Latitude, DN Value
   -122.08681,42.95930,183.798
   -122.08679,42.95930,181.868
   -122.08677,42.95930,186.463
   -122.08675,42.95930,188.191
   -122.08673,42.95930,191.080
   -122.08670,42.95930,190.712
   -122.08668,42.95930,187.086
   -122.08666,42.95930,183.662
   -122.08664,42.95930,183.558
   

   Entity_and_Attribute_Detail_Citation: none

   Entity_and_Attribute_Overview:

   BATHY is an ArcInfo GRID with the following attributes:

   Data Type: Floating
   

   BOUNDARY (UTM meters)

   Xmin =  568119.572
   Xmax =  577473.572
   Ymin = 4750592.815
   Ymax = 4758866.815
   

   STATISTICS (grid cell values, elevation in meters)

   Minimum Value =      1289.1
   Maximum Value =      1881.0
   Mean          =      1529.6
   Standard Deviation =  180.0
   

   BACKSTR is an ArcInfo grid with the following attributes:

   Data Type: Floating
   

   BOUNDARY (UTM meters)

   Xmin =  568094.347
   Xmax =  577512.347
   Ymin = 4750342.202
   Ymax = 4758964.202
   

   STATISTICS (grid cell values, digital number)

   Minimum Value =       26.228
   Maximum Value =      253.965
   Mean          =      203.641
   Standard Deviation =  11.623
   

   Entity_and_Attribute_Detail_Citation: none

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • James V. Gardner
   • Peter Dartnell

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) Coastal and Marine Geology (CMG)
   Geologist
   USGS, MailStop 999, 345 Middlefield Road
   Menlo Park, CA 94025-3561
   USA
   

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

Why was the data set created?

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 and backscatter data of Crater Lake, Oregon.

How was the data set created?

1. From what previous works were the data drawn?

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

   Date: 03-Aug-2000 (process 1 of 1)

   The bathymetry and backscatter data were collected along a continuous swath perpendicular to the direction of the ship using a Kongsberg Simrad EM1002 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 an XYZ ASCII format file (Longitude, Latitude, Attribute).

   Person who carried out this activity:
   

   James V. Gardner
   United States Geological Survey (USGS) Coastal and Marine Geology (CMG)
   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?

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?

   0.5 meters

3. How accurate are the heights or depths?

   0.05 percent of the water depth

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

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

How can someone get a copy of the data set?

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

Access_Constraints: None

Use_Constraints:

These data not intended for navigational purposes. 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. 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, USDOI, or U.S. Government, as to their suitability, content, usefulness, functioning, completeness, or accuracy.

1. Who distributes the data set? (Distributor 1 of 1)
   United States Geological Survey (USGS) Information Services
   Box 25286
   Denver, CO 80225
   USA
   

   (888)ASK-USGS (voice)
   

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

   S-00-OR data set

3. What legal disclaimers am I supposed to read?

   These data not intended for navigational purposes. 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. 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, USDOI, 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:	XYZ points with the Z coordinate indicating bathymetry (file bt_xyz.zip) or backscatter (file bk_xyz.zip). in format CSV (ASCII) The data are provided in comma-separated value (.csv) ASCII XYZ (longitude, latitude, value) format. Size: 78 megabytes
     Network links:	<http://pubs.usgs.gov/dds/dds-72/data/bt_xyz.zip> <http://pubs.usgs.gov/dds/dds-72/data/bk_xyz.zip>

     Data format:	bathymetry (grid bathy) and backscatter (grid backstr) in format ArcInfo GRID (version 8.0) Size: 400 megabytes
     Media you can order:	CD-ROM (format ISO9660)

   • Cost to order the data: None

Who wrote the metadata?

Dates:

Last modified: 25-Apr-2001

Metadata author:

Pete Dartnell
United States Geological Survey (USGS) Coastal and Marine Geology (CMG)
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 (FGDC-STD-001-1998)