DESCRIPTION OF THE DIGITAL DATABASE FOR 

  Marine Benthic Habitat Mapping of the West Arm, Glacier Bay National Park and Preserve, Alaska

  by Timothy O. Hodson , Guy R. Cochrane, and Ross D. Powell

  USGS SCIENTIFIC INVESTIGATIONS MAP 3253


  INTRODUCTION

  This digital database for the Marine Benthic Habitat Mapping 
  of the West Arm, Glacier Bay National Park and Preserve, Alaska 
  (USGS SIM-3253) includes several shapefiles (individual vector 
  datasets) along with supporting files and metadata. 

  All GIS data are in TRANSVERSE MERCATOR projection, 
  WGS_1984_UTM_Zone_8N
  Parameters:
    False_Easting: 500000.000000
    False_Northing: 0.000000
    Central_Meridian: -135.000000
    Scale_Factor: 0.999600
    Latitude_Of_Origin: 0.000000
  Linear Unit: Meter (1.000000)
  Geographic Coordinate System: 
    Name: WGS_1984
  Datum: WGS_1984

  Together with the Coastal and Marine Ecosystem Classification 
  System (CMECS) map sheets, the database provides 
  georeferenced information on the CMECS surficial geology,
  CMECS geoforms and observations of geology and benthic biology
  made during video surveying of the mapped of the area covered. 
  The database delineates map units that are identified by 
  CMECS, the FGDC standard for ecosystem description.  For
  more information about CMECS see http://www.csc.noaa.gov/cmecs.
  The spatial resolution (scale) of the database is 1:50,000 or less. 
  The content and character of the database, as well as how to obtain 
  the database, are described below. 


  CONTENT

  This database contains 3 shapefiles: 

  FishObs     		Points with geologic, geomorphic, 
               		and biologic observations.

  geoform       	Polygons of geomorphic features 
               		described using the CMECS system 

  surface_geology   	Polygons of surficial geology 
               		described using the CMECS system.
   

  File                   Description 
  -----------------------------------------------------------

  sim3253_readme.txt     This readme file

  FishObs.zip         	Shapefile components and metadata
			files for observation points.

  geoform.zip         	Shapefile components and metadata
			files for geoform polygons.

  surface_geology.zip   Shapefile components and metadata
			files for surface geology polygons.

  Each zip file contains detailed XML-format FGDC-style 
  metadata specific to the shapefile. This metadata is stored 
  as an xml file that can be viewed using ArcCatalog or other
  GIS metadata tools, a txt file, and an faq file that is easily 
  read with a web browsers (e.g., Firefox, Safari, Internet Explorer) 

  The material described above is available on the World-Wide 
  Web at http://pubs.usgs.gov/sim/3253/. 


  ZIP FILES

  The files described above are packaged within ZIP files. 
  Utilities to uncompress ZIP files are available for most 
  all operating systems and may be found readily with a 
  simple web search. 


  DIGITAL DATABASE FORMAT

  The shapefiless in this report were compiled in ArcInfo, a 
  commercial Geographic Information System (Environmental 
  Systems Research Institute,Redlands, California.  
  Data format:
  The SHP file contains the geospatial data. The SHX file contains
  the index of the geospatial data. The DBF file contains the attribute 
  data in dBASE format. The PRJ file contains the coordinate system 
  information (optional). The AVL file contains the legend information
  (optional). The SBN and SBX files contain the spatial index of the 
  geospatial data (optional). 


  OBTAINING THE DIGITAL DATABASE

  Go to 

  http://pubs.usgs.gov/sim/3253/


  to access the database package and the remainder of this 
  publication.

  ACKNOWLEDGMENTS

  We thank Carolyn Degnan and Jan Zigler for review of this readme, 
  the database package, and associated metadata.  Thanks also to
  Mike Diggles for web implementation.