Identification_Information:



  Citation:

    Citation_Information:

      Originator: US Army Engineer Joint Airborne Lidar Bathymetry Technical Center of Expertise.(ed.)

      Publication_Date: 20011000

      Title: Dahlia Shoals, Lake Michigan, Michigan

      Edition: 1.1

      Geospatial_Data_Presentation_Form: ArcInfo GRID

      Larger_Work_Citation:

        Citation_Information:

          Originator: Peter Barnes

          Originator: Guy Fleisher

          Originator: James V. Gardner

          Originator: Kristen Lee

          Publication_Date: 2003

          Title: Bathymetry and selected perspective views of 6 reef and coastal areas in Northern Lake Michigan

          Series_Information:

            Series_Name: USGS Open-File Report

            Issue_Identification: USGS OFR 03-120

          Publication_Information:

            Publication_Place: Menlo Park, CA

            Publisher: U.S. Geological Survey

          Online_Linkage: <http://geopubs.wr.usgs.gov/open-file/of03-120

  Description:

    Abstract: ArcInfo GRID format generated from 2001 Lidar survey. These data were collected by the SHOALS (Scanning Hydrographic Operational Airborne Lidar Survey) system which consists of an airborne laser transmitter/receiver capable of measuring 400 soundings per second.

    Purpose: The purpose of the survey was to provide bathymetry and albedo dat for utilization in habitat studies.

    Supplemental_Information: The system operates from a deHavilland DHC-6 Twin Otter flying at altitudes between 200 and 400 meters with a ground speed of about 100 knots. The SHOALS system also includes a ground-based data processing system for calculating acurate horizontal position and water depth. Lidar is an acronym for LIght Detection And Ranging. The system operates by emitting a pulse of light that travels from an airborne platform to the water surface where a small portion of the laser energy is backscattered to the airborne receiver. The remaining energy at the water's surface propogates through the water column and reflects off the sea bottom and back to the airborne detector. The time difference between the surface return and the bottom return corresponds to water depth. The maximum depth the system is able to sense is related to the complex interaction of radiance of bottom material, incident sun angle and intensity, and the type and quantity of organics or sediments in the water column. As a rule-of-thumb, the SHOALS system should be capable of sensing bottom to depths equal to two or three times the Secchi depth.

    



  Time_Period_of_Content:

    Time_Period_Information:

      Single_Date/Time:

        Calendar_Date: 20010800

    Currentness_Reference: Ground Condition



  Status:

    Progress: Complete

    Maintenance_and_Update_Frequency: Unknown



  Spatial_Domain:

    Bounding_Coordinates:

      West_Bounding_Coordinate: -085.242000

      East_Bounding_Coordinate: -085.158000

      North_Bounding_Coordinate: +45.670000

      South_Bounding_Coordinate: +45.600000



  Keywords:

    Theme:
      Theme_Keyword_Thesaurus: None
      Theme_Keyword: lidar survey
      Theme_Keyword: Hydrographic Survey
      Theme_Keyword: Lake Michigan
      Theme_Keyword: Dahlia Shoals

    Place:
      Place_Keyword_Thesaurus: None
      Place_Keyword: Lake Michigan
      Place_Keyword: Dahlia Shoals



  Access_Constraints: None





  Use_Constraints:



    Acknowledgement of the U.S. Army Engineer Joint Airborne Lidar Bathymetry Technical Center of Expertise (JALBCTX) would be appreciated in products derived from these data.







  Point_of_Contact:

    Contact_Information:

      Contact_Organization_Primary:

        Contact_Organization: U.S. Army Corps of Engineers JALBCTX

      Contact_Address:

        Address_Type: mailing and physical address

        Address: 109 St. Joseph Street

        City: Mobile

        State_or_Province: Alabama

        Postal_Code: 36602

        Country: USA

      Contact_Voice_Telephone: (334) 694-3721

      Contact_Facsimile_Telephone: (334) 690-3464

  
  Cross_Reference:

     Citation_Information:

       Originator: US Army Engineer Joint Airborne Lidar Bathymetry Technical Center of Expertise.(ed.)

       Publication_Date: 20011000

       Title: Boulder Reef, Lake Michigan, Michigan

       Online_Linkage: http://walrus.wr.usgs.gov/infobank/t/t101lm/html/t-1-01-lm.meta.html


    Native_Data_Set_Environment:

      SunOS, 5.8, sun4u UNIX

      ArcInfo version 8.0.2



     Browse_Graphic:

      Browse_Graphic_File_Name: http://geopubs.wr.usgs.gov/open-file/of03-120/images/map/newdahlia_mapL.jpg

      Browse_Graphic_File_Description:

        Shaded relief map view of Dahlia Shoals

      Browse_Graphic_File_Type: JPEG





Data_Quality_Information:



  Attribute_Accuracy:

    Attribute_Accuracy_Report: SHOALS has demonstrated capabilities that meet US Army Corps of Engineers Hydrographic Survey accuracy requirements for Class 1 surveys and the International Hydrographic Organization nautical charting standards for Order 1.



  Logical_Consistency_Report: None



  Completeness_Report: Complete



  Positional_Accuracy:

    Horizontal_Positional_Accuracy:

      Horizontal_Positional_Accuracy_Report: +/- 3 meters (1 sigma)

    Vertical_Positional_Accuracy:

      Vertical_Positional_Accuracy_Report: +/- 15 cm (1 sigma)



  Lineage:

    Source_Information:

      Source_Citation:

        Citation_Information:

          Originator: U.S. Army Corps of Engineers JALBTCX

          Publication_Date: 20011000

          Title: Dahlia Shoals, Lake Michigan, Michigan

          Edition: 1.1

      Type_of_Source_Media: CD-ROM

      Source_Time_Period_of_Content:

        Time_Period_Information:

          Single_Date/Time:

            Calendar_Date: 20010800

        Source_Currentness_Reference: Ground Condition

      Source_Citation_Abbreviation: None

      Source_Contribution: SHOALS



    Process_Step:

      Process_Description: The SHOALS airborne system acquires a tremendous volume of raw data during a single mission. The lidar data are unique and require a specialized Data Processing System (DPS) for post-processing. The DPS main funcions 1) import airborne data stored on high density data tape; 2) perform quality control checks on initial depths and horizontal positions; 3) provide display and edit capabilities; 4) calculate depth and position (XYZ) values for each sounding; and 5) output final positions and depths for each sounding. The depth readings are gridded into a common grid. The gridded data are converted to ArcInfo GRID format using ArcInfo's ASCIIGRID command.

      Process_Date: 20010900



Spatial_Data_Organization_Information:



  Direct_Spatial_Reference_Method: Raster



  Raster_Object_Information:

    Raster_Object_Type: Grid Cell



Spatial_Reference_Information:





  Horizontal_Coordinate_System_Definition:

    Planar:

      Grid_Coordinate_System:

        Grid_Coordinate_System_Name: Universal Transverse Mercator

        Universal_Transverse_Mercator:

          UTM_Zone_Number: 16

          Transverse_Mercator:

            Scale_Factor_at_Central_Meridian: 0.9996

            Longitude_of_Central_Meridian: -85.20000

            Latitude_of_Projection_Origin: 0.00000

            False_Easting: 0.00

            False_Northing: 0.00

      Planar_Coordinate_Information:

        Planar_Coordinate_Encoding_Method: coordinate pair

        Coordinate_Representation:

          Abscissa_Resolution: 4.0

          Ordinate_Resolution: 4.0

        Planar_Distance_Units: Meters

    Geodetic_Model:

      Horizontal_Datum_Name: WGS84

      Ellipsoid_Name: WGS84

      Semi-major_Axis: 6378137.00 meters

      Denominator_of_Flattening_Ratio: 0.003352811





Entity_and_Attribute_Information:





  Overview_Description:

    Entity_and_Attribute_Overview:

      dahliagrd is an ArcInfo GRID with the following attributes:

      Cell Size = 4.000

      Data Type: Floating Point

      Number of Rows = 2152

      Number of Columns = 1439



      BOUNDARY

      Xmin = 638209.450

      Xmax = 643965.450

      Ymin = 5051545.406

      Ymax = 5060153.406



      STATISTICS

      Minimum Value = -180.200

      Maximum Value = -146.200

      Mean          = -161.207

      Standard Deviation = 4.932



    Entity_and_Attribute_Detail_Citation: none



Distribution_Information:



  Distributor:

    Contact_Information:

      Contact_Organization_Primary:

        Contact_Organization: U.S Geological Survey

        Contact_Person: Peter Barnes

      Contact_Address:

        Address_Type: mailing and physical address

        Address: MS999 345 Middlefield Road

        City: Menlo Park

        State_or_Province: CA

        Postal_Code: 94025



      Contact_Voice_Telephone: 916-329-5265



  Distribution_Liability:

    These data not intended for navigational purposes.



    Although these data have been used by the U.S. Geological Survey, U.S. Departmempnt 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 cisions 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.



  Standard_Order_Process:

    Digital_Form:

      Digital_Transfer_Information:

        Format_Name: ArcInfo GRID

      Digital_Transfer_Option:

        Online_Option:

          Computer_Contact_Information:

            Network_Address:

              Network_Resource_Name: <http://geopubs.wr.usgs.gov/open-file/of03-120>

    Fees: None





Metadata_Reference_Information:

  Metadata_Date: 20030130

  Metadata_Review_Date: 20030200

  Metadata_Contact:

    Contact_Information:

      Contact_Organization_Primary:

        Contact_Organization: USGS

        Contact_Person: Kristen Lee

      Contact_Position: Physical Science Technican

      Contact_Address:

        Address_Type: mailing and physical address

        Address: USGS, MailStop 999, 345 Middlefield Road

        City: Menlo Park

        State_or_Province: CA

        Postal_Code: 94025-3561

        Country: USA

      Contact_Voice_Telephone: (650) 329-5260

      Contact_Facsimile_Telephone: (650) 329-5411

      Contact_Electronic_Mail_Address: kmlee@usgs.gov



  Metadata_Standard_Name: Content Standard for Digital Geospatial Metadata ("CSDGM version 2")



  Metadata_Standard_Version: FGDC-STD-001-1998