Identification_Information:
  Citation:
    Citation_Information:
      Originator: Terri Arnold
      Publication_Date: Unpublished Material
      Publication_Time: 2008
      Title: clusters -- clustered wells with similar water quality conditions
      Geospatial_Data_Presentation_Form: vector digital data
      Series_Information:
      Publication_Information:
      Online_Linkage: \\IGSASCEWWSMAGEL\Terri\glacial\report_plans\hydrochem\report_text_01242006\Data_archive\spatial_data\hydrochem.gdb
      Larger_Work_Citation:
        Citation_Information:
          Publication_Date: 2008
          Title: From SIR2008-5015, Hydrochemical regions of the glacial aquifer system and their environmental and water quality characteristics
          Series_Information:
            Series_Name: USGS SIR
            Issue_Identification: 2008-5015
  Description:
    Abstract:
      This data set was created for SIR2008-5015 to map hydrochemical regions of the glacial aquifer system.  It was created from cluster analysis results clustering of wells with similar major and mior ion concentrations. An unsupervised classification method, such as cluster analysis, provides a means of grouping wells based on the actual chemical concentration data (variables) rather than on pre-defined group characteristics. In this study, the grouped objects are wells and the variables used to form the groups are major- and minor-ion concentrations (Ca, Cl, F, Mg, K, Na, SO4, and HCO3). The goal is to identify groups of wells that are more similar to each other, with respect to ion concentrations, than they are to wells in any other group; in other words, the goal is minimizing within group differences while maximizing between group differences (Massart and Kaufman, 1983; Romesburg, 1984; Everitt, 1980; Kachigan, 1986; Hair and others, 1998). Within- and between-group differences are measured by the Euclidean distance between points (distance in multidimensional space). In the case of this analysis, the multidimensional space has eight dimensions, one for each variable used to define the clusters. Because distance measures are sensitive to variations in measurement scales and magnitudes among the variables being clustered, the variables were standardized by subtracting the mean and dividing by the standard deviation for each variable. This type of standardization (z.score) has a mean of zero (0) and standard deviation of one (1) which allows the variables to be examined on a similar scale (Hair and others, 1998).
      See published report for references and firther description of clusters.
    Purpose: This data set was created for SIR2008-5015 to map hydrochemical regions of the glacial aquifer system.
  Time_Period_of_Content:
    Time_Period_Information:
      Single_Date/Time:
        Calendar_Date: 2008
        Time_of_Day: unknown
    Currentness_Reference: publication date
  Status:
    Progress: Complete
    Maintenance_and_Update_Frequency: None planned
  Spatial_Domain:
    Bounding_Coordinates:
      West_Bounding_Coordinate: -151.779710
      East_Bounding_Coordinate: -57.496206
      North_Bounding_Coordinate: 71.628642
      South_Bounding_Coordinate: 33.311967
  Keywords:
    Theme: water-quality cluster designation
      Theme_Keyword_Thesaurus: none
    Place:
      Place_Keyword: United States
  Access_Constraints: For internal use only.
  Use_Constraints: For internal use only.
  Point_of_Contact:
    Contact_Information:
      Contact_Person_Primary:
        Contact_Person: Terri Arnold
        Contact_Organization: US Geological Survey
      Contact_Position: Cartographer/GIS Specialist
      Contact_Voice_Telephone: 217-328-9702
      Contact_Facsimile_Telephone: 217-344-0082
      Contact_Electronic_Mail_Address: tlarnold@usgs.gov
  Native_Data_Set_Environment: Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.2.4.1420
Data_Quality_Information:
  Lineage:
    Source_Information:
      Source_Citation:
        Citation_Information:
          Originator: Terri Arnold
          Geospatial_Data_Presentation_Form: map
          Publication_Information:
            Publication_Place: not published
            Publisher: USGS
          Other_Citation_Details:
          Online_Linkage: none
    Process_Step:
      Process_Description:
        Ran cluster analysis in SPlus.  Joined cluster results by well identification number (STAID) to shapefile of well locations. Then exported as a shapefile.
      Process_Date: 2007
      Process_Contact:
        Contact_Information:
          Contact_Person_Primary:
            Contact_Person: Terri Arnold
            Contact_Organization: USGS
          Contact_Position: GIS Specialist
          Contact_Voice_Telephone: 217-328-9702
          Contact_Electronic_Mail_Address: tlarnold@usgs.gov
    Process_Step:
      Process_Description: import into geodatabase
      Process_Date: 2008
    Process_Step:
      Process_Description: Metadata imported.
      Source_Used_Citation_Abbreviation: D:\temp\xml181.tmp
Spatial_Data_Organization_Information:
  Direct_Spatial_Reference_Method: Vector
  Point_and_Vector_Object_Information:
    SDTS_Terms_Description:
      SDTS_Point_and_Vector_Object_Type: Entity point
      Point_and_Vector_Object_Count: 1719
  Raster_Object_Information:
    Raster_Object_Type: Pixel
    Row_Count: 7276
    Column_Count: 13024
    Vertical_Count: 1
Spatial_Reference_Information:
  Horizontal_Coordinate_System_Definition:
    Planar:
      Map_Projection:
        Map_Projection_Name: Albers Conical Equal Area
        Albers_Conical_Equal_Area:
          Standard_Parallel: 29.500000
          Standard_Parallel: 45.500000
          Longitude_of_Central_Meridian: -96.000000
          Latitude_of_Projection_Origin: 23.000000
          False_Easting: 0.000000
          False_Northing: 0.000000
      Planar_Coordinate_Information:
        Planar_Coordinate_Encoding_Method: coordinate pair
        Coordinate_Representation:
          Abscissa_Resolution: 0.000100
          Ordinate_Resolution: 0.000100
        Planar_Distance_Units: meters
    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:
    Attribute:
      Attribute_Label: OBJECTID
      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: SUID
      Attribute_Definition: 4-character study unit abbreviation 
      Attribute_Definition_Source: NAWQA data warehouse
    Attribute:
      Attribute_Label: STAID
      Attribute_Definition: 15-character well identification number
      Attribute_Definition_Source: NAWQA data warehouse
    Attribute:
      Attribute_Label: ALLLOG_STA
      Attribute_Definition: cluster designation (character field)
      Attribute_Definition_Source: SPlus assigned
      Attribute_Domain_Values: 1, 2, 3, 4, 5, NA
    Attribute:
      Attribute_Label: allogstncl
      Attribute_Definition: cluster designation (integer field)
      Attribute_Definition_Source: SPlus assigned
      Attribute_Domain_Values: 1, 2, 3, 4, 5, 0
    Attribute:
      Attribute_Label: FAMEAREA
      Attribute_Definition: Name of framework area
      Attribute_Definition_Source: Terri Arnold
      Attribute_Domain_Values: EAST, CENTRAL, WEST-CENTRAL, WEST
Distribution_Information:
  Resource_Description: By Request to Terri Arnold (tlarnold@usgs.gov)
Metadata_Reference_Information:
  Metadata_Date: 20080904
  Metadata_Contact:
    Contact_Information:
      Contact_Person_Primary:
        Contact_Person: Terri Arnold
        Contact_Organization: USGS
      Contact_Position: GIS Specialist
      Contact_Address:
        Address_Type: mailing and physical address
        Address: 1201 W University Ave, Suite 100
        City: Urbana
        State_or_Province: IL
        Postal_Code: 61801
        Country: USA
      Contact_Voice_Telephone: 217-328-9702
      Contact_Electronic_Mail_Address: tlarnold@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
