Metadata for US_AQUIFERS

 Table of Contents 
Identification_Information
     Abstract 
     Purpose 
     Supplemental Information 
Data_Quality_Information
Spatial_Data_Organization_Information
Entity_and_Attribute_Information
     Detailed Description
     Overview 
Distribution_Information
Metadata_Reference_Section


Identification_Information 
Citation_Information 
    Originator: James A. Miller  (comp.)
    Publication_Date: 1998
    Title: Principle Aquifers of the 48 Contiguous United States
    Geospatial_Data_Presentation_Format: map
    Publication_Information
        Publication_Place: Madison, Wisconsin
        Publisher: U.S. Geological Survey
    Online_Linkage: http://www.nationalatlas.gov/aquifersm.html


Description  
    Abstract
    This data set contains the shallowest principal aquifers of the
    contiguous United States, portrayed as polygons. The data set was
    developed as part of the effort to produce the maps published at
    1:2,500,000 in the printed series "Ground Water Atlas of the United
    States". The published maps contain base and cultural features not
    included in these data.
     
    This dataset was downloaded from http://nationalatlas.gov by the
    Cornell University GIS Group in shapefile format.  The Cornell GIS
    Group converted the shapefile to an ARC/INFO coverage and created this
    metadata file with information from
    http://www.nationalatlas.gov/aquifersm.html
     
     
     
    Purpose
    These data are intended for use in publications, at a scale of
    1:2,500,000 or smaller. Due to the small scale, the primary intended
    use is for regional and national data display and analysis, rather
    than specific local data analysis.
     
     
Supplemental_Information
    Procedures_Used
     
    Aquifer outcrop line work for each GWA chapter was compiled on mylar
    at a scale of 1:2,000,000, and reduced to 1:2,500,000 for further
    production work. For chapters HA 730-G, -H, and -J, the outcrop lines
    were scribed at a line width of 0.006 inch. Film positives made from
    the scribed materials were scanned on a drum scanner, vectorized, and
    converted to ARC/INFO coverages. For chapters HA 730-B, -C, -D, -E,
    -F, -I, -K, -L, and -M, the aquifer compilation was either hand
    digitized, and (or) scanned on a drum scanner, vectorized and
    converted to ARC/INFO coverages. The data were then checked, cleaned
    up, and attribute creation was done.
     
    The ARC/INFO coverages were plotted and checked against the source
    compilations.  Polygons were attributed using Arcedit. The coverages
    for GWA chapters HA 730-B, -C, -D, -E, -F, -I, -K, -L, and -M were
    used to generate output files that were imported into Adobe
    Illustrator for map publication. Each completed map, at a scale of
    1:2,500,000, was reviewed for content and accuracy by the chapter lead
    cartographer, Water Resources Division Geohydrologic Map Editor, and
    chapter author.
     
    Individual chapter coverages were appended into one continuous
    coverage. Arcedit was used for edgematching and to remove duplicate
    labels. No DISSOLVE was done on the coverage; an equivalent of a
    DISSOLVE was done manually in Arcedit in conjunction with attribute
    checking, by removing arcs that divided adjacent polygons with the
    same attributes. Several iterations of editing were performed. These
    mostly involved ensuring all polygons had labels and aquifer
    information and ensuring polygons had correct aquifer information. No
    polygons were removed for generalization.
     
    Plots of the national aquifers file were made at 1:2,500,000,
    covering the areas of the regional GWA chapters. Each plot was
    compared to the printed GWA chapter aquifer maps. Where applicable
    (chapters HA 730-B, -C, -D, -E, -F, -I, -K, - L, and -M), an Adobe
    Illustrator file of the coverage data was compared on-screen with the
    Illustrator file used to print the published map. Discrepancies
    between the coverage file and print file were noted, and the coverage
    updated to match the published map. Where a line appeared to shift
    noticeably (approximately 1/8 inch at a scale of 1:2,500,000) across
    the boundary of two adjacent GWA chapter regions, the line was
    adjusted for a smoother appearance. The adjustments may have been made
    on one or both sides of the region boundary, depending on a
    cartographic assessment of the instance.
     
    Coastline Location The 1:2,500,000 principal aquifer maps in the
    Ground Water Atlas publications used a coastline and international
    boundary, derived either from the map separates from the National
    Atlas of the United States of America (published 1970), or from the
    Digital Line Graph (DLG) data created from the 1970 National Atlas.
    GWA chapters HA 730-G, -J, and -H used coastline and boundary filmwork
    photo-mechanically reduced from the 1:2,000,000 National Atlas map
    separates. The remaining chapters used coastline and boundary data
    from the DLGs. A revision of the DLG data took place in 1997, after
    the creation of the chapter aquifer map data.
     
    After the edgematching, a decision was made to replace the coast and
    international boundary of this national- level aquifer data with one
    derived from a newer version of 1997 DLG data.  State boundary data
    from the U.S. Geological Survey National Mapping Division was used to
    provide the coastline and two aquifer boundaries that coincide with
    State lines. A publicly available version of this data and its
    metadata (Map Layer Theme: States) can be found at:
    
     
    The existing outline (coastline and international boundary line) was
    removed, the new outline added to the coverage, and the remaining
    aquifer contact lines snapped to the new outline. The coverage was
    re-cleaned, data categories checked onscreen and with plots, and
    corrected.  Line and labeling corrections, such as undershoots,
    overshoots, and improper labels were corrected in Arcedit.
     
    There are some slight locational differences between this data set
    and the printed GWA chapters. For example, there are several small
    differences in the number of small islands in coastal areas and the
    categorization of these small islands was assigned to either the
    nearby principal aquifer category or as Not a principal aquifer,
    depending on the location and categorization of similar small islands
    in the printed GWA chapters. There are other differences in the
    categorization of some land/shoreline-related features. For example,
    an area symbolized as a bay in a GWA chapter may be land in this data
    set.
     
    Western Montana During the review of a printed map made from this
    national-level aquifer data, the compiler, James A. Miller, requested
    a change in the representation of aquifers in western Montana. The
    area affected is in the following counties: Lincoln, Flathead,
    Sanders, Lake, Mineral, Missoula, Powell, Ravalli, Granite, Lewis and
    Clark, Deer Lodge, Silver Bow, Jefferson, Broadwater, Gallatin,
    Beavershead, and Madison. These areas fall under the Northern Rocky
    Mountain Intermontane Basins Regional Aquifer Systems Analysis (RASA).
    With one exception, the aquifers, as shown in GWA chapter I, figure 7
    in the listed counties were removed and replaced with
    unconsolidated-deposit areas as shown in GWA chapter HA 730-I, figure
    6. The exception is an area in northern Flathead county, listed as an
    Upper Tertiary aquifer in GWA chapter I, figure 7, that was retained
    as an area but reclassified as a Lower Tertiary aquifer.
     
     
    Revisions
    See procedures used section of this metadata file.
     
     
    Reviews_Applied_to_Data
    information not available
     
     
    Related_Spatial_and_Tabular_Data_Sets
     
    Related Spatial and Tabular Data Sets A data set showing the extent
    of glacial deposits is included in the online, interactive National
    Atlas of the United States, but is not available to download. This
    data set shows the southern limit of glaciation in the United States;
    areas north of the limit line may contain significant sand and gravel
    glacial deposits that are important sources of water for local areas.
     
     
    References_Cited
    Planert, M. and Williams, J.S. (comp.), 1995, Ground Water Atlas of
    the United States-Segment 1: California, Nevada, Hydrologic
    Investigations Atlas, HA 730-B, Reston, Virginia: U.S. Geological
    Survey.
     
    Robson, S.G. and Banta, E.R. (comp.), 1995, Ground Water Atlas of the
    United States-Segment 2: Arizona, Colorado, New Mexico, Utah,
    Hydrologic Investigations Atlas, HA 730-C, Reston, Virginia: U.S.
    Geological Survey.
     
    Miller, J.A. and Appel, C.L. (comp.)  1998, Ground Water Atlas of the
    United States-Segment 3: Kansas, Missouri, Nebraska, Hydrologic
    Investigations Atlas, HA 730-D, Reston, Virginia Publisher: U.S.
    Geological Survey.
     
    Ryder, P.D. (comp.), 1996, Ground Water Atlas of the United
    States-Segment 4: Oklahoma, Texas,  Hydrologic Investigations Atlas,
    HA 730-E, Reston, VA: U.S. Geological Survey.
     
    Renken, R.A. (comp.), 1998, Ground Water Atlas of the United
    States-Segment 5: Arkansas, Louisiana, Mississippi, Hydrologic
    Investigations Atlas, HA 730-F, Reston, VA: U.S. Geological Survey.
     
    Miller, J.A. (comp.), 1990, Ground Water Atlas of the United
    States-Segment 6: Alabama, Florida, Georgia, and South Carolina,
    Hydrologic Investigations Atlas, HA 730-G, Reston, VA, U.S. Geological
    Survey.
     
    Whitehead, R.L. (comp.), 1994, Ground Water Atlas of the United
    States-Segment 7: Idaho, Oregon, Washington, Hydrologic
    Investigations Atlas, HA 730-H, Reston, VA: U.S. Geological Survey.
     
    Whitehead, R.L. (comp.), 1996, Ground Water Atlas of the United
    States-Segment 8: Montana, North Dakota, South Dakota, Wyoming,
    Hydrologic Investigations Atlas, HA 730-I, Reston, VA, U.S.
    Geological Survey.
     
    Olcott, P.G. (comp.), 1992, Ground Water Atlas of the United
    States-Segment 9: Iowa, Michigan, Minnesota, Wisconsin, Hydrologic
    Investigations Atlas, Reston, VA: U.S. Geological Survey.
     
    Lloyd, O.B., Jr., and Lyke, W.L. (comp.), 1995, Ground Water Atlas
    of the United States-Segment 10: Illinois, Indiana, Kentucky, Ohio,
    Tennessee, Hydrologic Investigations Atlas, HA 730-K, Reston, VA: U.S.
    Geological Survey.
     
    Trapp, H., Jr. and Horn, M.A. (comp.), 1997, Ground Water Atlas of
    the United States-Segment 11: Delaware, Maryland, New Jersey, North
    Carolina, Pennsylvania, Virginia, West Virginia, Hydrologic
    Investigations Atlas,  HA 730-L, Reston, VA: U.S. Geological Survey.
     
    Olcott, P.G. (comp.), 1995, Ground Water Atlas of the United
    States-Segment 12: Connecticut, Maine, Massachusetts, New Hampshire,
    New York, Rhode Island, Vermont, Hydrologic Investigations Atlas,
    HA 730-M, Reston, VA: U.S. Geological Survey.
     
    United States Geological Survey, 1998, State Boundaries, Reston, VA:
    U.S. Geological Survey.
     
    U.S. Geological Survey, Water Resources Division, Unpublished
    material, National aquifers file, Reston, VA: U.S. Geological Survey.
     
     
     
    Notes
     
    Although these data have been processed successfully on a computer
    system at the U.S. Geological Survey, no warranty expressed or implied
    is made by the U.S. Geological Survey regarding the utility of the
    data on any other system, nor shall the act of distribution constitute
    any such warranty.
     
     
Time_Period_of_Content
    Single_Date/Time
    Calendar_Date: 1998
    Currentness_Reference
    1998
     
     
Status
    Progress: complete
    Maintenance_and_Update_Frequency
    as needed 					
     
     
Spatial_Domain
    Bounding_Coordinates
    West_Bounding_Coordinate:  
    East_Bounding_Coordinate:  
    North_Bounding_Coordinate:  
    South_Bounding_Coordinate:  


Keywords
    Theme
        Theme_Keyword_Thesaurus: None
        Theme_Keyword:  United States, Aquifers
    Place
        Place_Keyword_Thesaurus: None
        Place_Keyword:  United States
    Stratum
        Stratum_Keyword_Thesaurus: None
        Stratum_Keyword:
    Temporal
        Temporal_Keyword_Thesaurus: None
        Temporal_Keyword:


Access_Constraints
None.  Acknowledgment of the Ground Water Atlas of the United States
and (or) the National Atlas of the United States of America would be
appreciated in products derived from these data.
 
 
 
Use_Constraints
The Ground Water Atlas of the United States (GWA) chapters include
additional information that may be relevant to the use of this data
set, such as maps of alluvial and glacial aquifers that overlie the
aquifers in this data set, as well as other information described
below.
The areal extent of the aquifers, as shown in this data set,
represents the area in which a named aquifer is the shallowest of the
principal aquifers. These aquifer areas are not necessarily the only
areas in which ground water can be withdrawn, for two reasons: 1) The
aquifers shown may have a larger areal extent than is represented
here. The boundaries in this data set generally represent an
interpretation of the surface location (outcrop), or near- surface
location (shallow subcrop) of the uppermost principal aquifer for the
area. An aquifer may extend beyond the area shown, but be overlain by
one or more other aquifers, and (or) low-permeability material.
2) There may be areas of water-bearing surficial material not shown
in this data set. Major alluvial aquifers that occur along main
watercourses are not shown. Significant unconsolidated sand and
]gravel aquifers, that are not indicated in this data set but are
important sources of water, may occur locally in glaciated regions.
The user of this data set is advised that to get complete information
regarding areas that serve as sources of water, more information
about surficial aquifers needs to be obtained, particularly in
glaciated areas.
This data set was constructed by combining data created for or from
the regional GWA chapters.  Minor aquifers that are important local
sources of water were mapped in some regions, so the regional maps in
the GWA may show more detail than this data set. The juxtaposition of
regionally mapped aquifers has led to some instances where an aquifer
outcrop or shallow subcrop is bounded by a State line. This is a
result of the regional mapping and national categorization methods
used and is not meant to imply a hydrogeologic change coincident with
a State boundary.
The aquifer outcrop and shallow subcrop boundaries represent broad,
regional categories and should not be interpreted as site-specific.
Comments regarding the names of aquifers or the hydrogeologic
interpretation of the aquifers can be directed to the U.S. Geological
Survey, Water Resources Division, Office of Ground Water, Roy
Sonenshein, sunshine@usgs.gov, (305) 717-5824.
This data set was used as part of the effort to publish a
1:5,000,000-scale Principal Aquifers map in the National Atlas of
the United States of America series of printed maps. The printed map
can be considered a representation of this data set with the
exceptions of: the smaller scale, slight differences in the coastline
due to generalization, base and cultural information, and delineation
of the glacial-deposit area.
These data were developed in conjunction with the publication of
the GWA. For documentation purposes, areas are referred to by their
corresponding GWA chapter letter, or by State. This list shows the
relationship between State names and GWA chapters:
 
HA 730-B        Segment 1-California, Nevada
HA 730-C        Segment 2-Colorado, Utah, New Mexico, Arizona
HA 730-D        Segment 3-Kansas, Missouri, Nebraska
HA 730-E        Segment 4-Texas, Oklahoma
HA 730-F        Segment 5-Arkansas, Louisiana, Mississippi
HA 730-G        Segment 6-Alabama, Florida, Georgia, South Carolina
HA 730-H        Segment 7-Idaho, Oregon, Washigton
HA 730-I        Segment 8-Montana, North Dakota, South Dakota, Wyoming
HA 730-J        Segment 9-Iowa, Michigan, Minnesota, Wisconsin
HA 730-K        Segment 10-Illinois,Indiana, Kentucky, Ohio,
Tennessee
HA 730-L        Segment 11-Delaware, Maryland, New   North Carolina,
Pennsylvania, Virginia,West Virginia
HA 730-M        Segment 12-Connecticut, Maine, Massachusetts, New
Hampshire, New York, Rhode Island, Vermont
 
Refer to:  for
a graphic depiction of the GWA chapter regions, as well as more
information about the GWA.
 
Although these spatial data can stand alone, it may be helpful to
refer to the printed GWA chapters when using the data. There are three
subject areas in which there are significant differences between this
data set and the printed chapters: category changes, which are
described below; coastline location, and the representation of
aquifers in Western Montana, both of which are discussed in the
Process Description under Lineage.
 
Category Changes Because the GWA regional chapters were written by
different authors, there were areas of different interpretations and
category delineations, aquifer names, etc., that became apparent when
combining the regions. In most cases, the name and delineation of the
aquifer is identical between this data set and the GWA printed maps,
but there are several areas of differences.  In some cases, a single
aquifer from a GWA chapter is represented among multiple aquifers in
this data set.  The following listings show the differences between
aquifer names in the GWA chapters and the aq_name and aq_code used in
this data set.  See the Entity and Attribute Information section for
definitions of the data attributes.
 
GWA chapter HA 730-B
Name from fig 11, page B4     aq_code-aq_name
Basin and Range volcanic-     601-Southern Nevada
rock aquifers                   volcanic-rock aquifers
 
Coastal Basins aquifers       103-California Coastal Basin
aquifers
 
Northern California Basin     104-Pacific Northwest
fill aquifers                     basin-fill aquifers
GWA chapter HA 730-C
Name from fig 11, page C4
Names and categories the same
GWA chapter HA 730-D
Name from fig 5, page D4      aq_code-aq_name
Mississippi embayment         109-Mississippi River Valley
aquifer system                    alluvial aquifer
 
Great Plains aquifer          304-Lower Cretaceous
aquifers system
 
Confining unit                999-Not a principal aquifer
 
Not a principal aquifer       999-Not a principal aquifer
 
Dune sand                     107-High Plains aquifer
GWA chapter HA 730-E
Name from fig 4, page E3      aq_code-aq_name
EDWARDS-TRINITY AQUIFER SYSTEM
Edwards-Trinity aquifer       501-Edwards-Trinity aquifer
system
 
Edwards aquifer               501-Edwards-Trinity aquifer
system
 
Trinity aquifer               501-Edwards-Trinity aquifer
system
 
Confining unit                999-Not a principal aquifer
GWA chapter HA 730-F
Name from fig 7, page 4       aq_code-aq_name
MAJOR AQUIFER SYSTEMS
Surficial aquifer system      109-Mississippi River Valley
alluvial aquifer
203-Mississippi embayment
aquifer system
501-Edwards-Trinity aquifer
system
999-Not a principal aquifer
 
Mississippi embayment         109-Mississippi River Valley
aquifer system                    alluvial aquifer
203-Mississippi embayment
aquifer
204-Southeastern Coastal
Plain aquifer system
999-Not a principal aquifer
 
MINOR AQUIFERS AND AQUIFER SYSTEMS - Aquifer systems in
rocks of cretaceous age
Edwards-Trinity aquifer       501-Edwards-Trinity aquifer
system (Trinity aquifer)          system
 
Tokio-Woodbine aquifer        999-Not a principal aquifer
 
Ouachita Mountains aquifer    999-Not a principal aquifer
 
CONFINING SYSTEMS AND CONFINING UNITS
Western Interior Plains       999-Not a principal aquifer
confining systems
 
Confining unit                109-Mississippi River Valley
alluvial aquifer
203-Mississippi embayment
aquifer system
999-Not a principal aquifer
GWA chapter HA 730-G
Name from fig 3, page 3       aq_code-aq_name
Sand and gravel aquifer       201-Coastal lowlands aquifer
system
 
Piedmont and Blue Ridge       999-Not a principal aquifer
aquifers
 
Appalachian Plateaus          310-Pennsylvanian aquifers
aquifers
 
Interior Low Plateaus         503-Mississippian aquifers
aquifers
 
Confining unit                999-Not a principal aquifer
GWA chapter HA 730-H
Name from fig 5, page H4      aq_code-aq_name
Unconsolidated-deposit        104-Pacific Northwest
aquifers                          basin-fill aquifers
112-Puget-Willamette Lowland
aquifer system
105-Northern Rocky Mountains
Intermontane basins
aquifer system
101-Basin and Range aquifers
 
Pliocene and younger          603-Pliocene and younger
basaltic-rock aquifers            basaltic-rock aquifers
606-Snake River Plain
aquifer system
 
Miocene basaltic-rock         607-Columbia Plateau aquifer
aquifers                          system
604-Miocene basaltic-rock
aquifers
 
Aquifers in pre-Miocene       401-Basin and Range
rocks                             carbonate-rock aquifers
999-Not a principal aquifer
GWA chapter HA 730-I.  See Process Description regarding
differences between this data and the printed Ground Water
Atlas chapter in Western Montana
Name from fig 7, page I4      aq_code-aq_name
Quaternary volcanic and       605-Volcanic and
sedimentary rock aquifers         sedimentary-rock
aquifers
 
Upper Tertiary aquifers       107-High Plains aquifer
316-Wyoming Tertiary
aquifers
 
Lower Tertiary aquifers       107-High Plains aquifer
314-Lower Tertiary aquifers
 
Upper Cretaceous aquifers     301-Colorado Plateaus
aquifers
315-Upper Cretaceous
aquifers
 
Lower Cretaceous aquifers     301-Colorado Plateaus
aquifers
304-Lower Cretaceous aquifer
 
Confining unit                301-Colorado Plateaus
aquifers
GWA chapter HA 730-J
Name from fig 7, page J4      aq_code-aq_name
Cretaceous aquifer            304-Lower Cretaceous
aquifers
 
MISSISSIPPIAN AQUIFER
Carbonate rocks               503-Mississippian aquifers
 
Sandstone                     311-Mississippian aquifers
of Michigan
 
Crystalline-rock aquifer      999-Not a principal aquifer
 
Confining unit                999-Not a principal aquifer
GWA chapter HA 730-K
Name from fig 5, page K4      aq_code-aq_name
Blue Ridge aquifers           308-Early Mesozoic basin
aquifers
999-Not a principal aquifer
 
MISSISSIPPI EMBAYMENT AQUIFER SYSTEM
Upper Claiborne, middle       203-Mississippi embayment
Claiborne, middle Wilcox,         aquifer system
and lower Wilcox              109-Mississippi River Valley
alluvial aquifer
 
McNairy-Nacatoch              204-Southeastern Coastal
Plain aquifer system
 
Confining unit                999-Not a principal aquifer
GWA chapter HA 730-L
Name from fig 7, page L4      aq_code-aq_name
 
NORTHERN ATLANTIC COASTAL PLAIN AQUIFER SYSTEM
Surficial aquifer             111-Surficial aquifer system
 
Chesapeake aquifer            205-Northern Atlantic
Coastal Plain aquifer system
 
Castle Hayne-Aquia aquifer    418-Castle Hayne aquifer
 
Severn-Magothy aquifer        205-Northern Atlantic
Coastal Plain aquifer system
 
Peedee-upper Cape Fear        205-Northern Atlantic
quifer                            Coastal Plain aquifer system
 
Potomac aquifer               205-Northern Atlantic
Coastal Plain aquifer system
 
PIEDMONT AND BLUE RIDGE AQUIFERS
Aquifers in early Mesozoic    308-Early Mesozoic basin
basins                            aquifers
 
Carbonate-rock aquifers       417-Piedmont and Blue Ridge
carbonate-rock aquifers
 
Crystalline-rock aquifers     999-Not a principal aquifer
 
Valley and Ridge              505-Valley and Ridge
carbonate-rock aquifers           carbonate-rock aquifers
416-New York and New England
carbonate-rock aquifers
 
APPALACHIAN PLATEAUS
Permian and Pennsylvanian     310-Pennsylvanian aquifers
aquifers
GWA chapter HA 730-M
Name from fig 10, page M5     aq_code-aq_name
CARBONATE-ROCK AQUIFERS
New York and New England      416-New York and New England
carbonate-rock aquifers
 
Valley and Ridge              416-New York and New England
carbonate-rock aquifers
 
SANDSTONE AQUIFERS
Mesozoic sandstone and        308-Early Mesozoic basin
basalt of the Newark              aquifers
Supergroup
 
Lower Paleozoic               309-New York sandstone
 aquifers
 
CRYSTALLINE-ROCK AQUIFERS
Adirondack                    999-Not a principal aquifer
 
New England                   999-Not a principal aquifer
 
Related Spatial and Tabular Data Sets A data set showing the extent
of glacial deposits is included in the online, interactive National
Atlas of the United States, but is not available to download. This
data set shows the southern limit of glaciation in the United States;
areas north of the limit line may contain significant sand and gravel
glacial deposits that are important sources of water for local areas.
 
A data set of aquifers of Alaska is in work.
 
A data set of aquifers of Puerto Rico and the U.S. Virgin Islands is
in work.
 
A data set of aquifers of Hawaii is planned.
 
The final data are being served to the public in the following
formats: Spatial Data Transfer Standard (SDTS), ARC/INFO Export, or
ArcView Shapefile.
 
 
 
Point_of_Contact: See Distribution_Information for contact information.


Data_Set_Credit
This data set was created and modified over a period of at least
five years by several staff members of the U.S. Geological Survey
Water Resources Division Cartographic and Publications Program in
Madison, Wisconsin. Completion of this data set and associated
metadata was funded, in part, under a cooperative joint funding
agreement between the U.S. Geological Survey and the U.S.
Environmental Protection Agency.
 
 
 
Security_Information
    Security_Classification_System: None
    Security_Classification:  UNCLASSIFIED
    Security_Handling_Description: None


Native_Data_Set_Environment: SunOS UNIX, ARC/INFO version 7.2.1


Cross_Reference
    Originator: U.S. Geological Survey
    Publication_Date: 
    Publication_Time: 
    Title: 
    Edition: 
    Geospatial_Data_Presentation_Form: 
    Series_Information
        Series_Name: 
        Issue_Identification: 
    Publication_Information
        Publication_Place: 
        Publisher: 
    Other_Citation_Details: 
    Online_Linkage: 
    Larger_Work_Citation: 





Data_Quality_Information
Attribute_Accuracy
    Attribute_Accuracy_Report: See Entity_Attribute_Information


    Quantitative_Attribute_Accuracy_Assessment
        Attribute_Accuracy_Value:  See Explanation
        Attribute_Accuracy_Explanation:
           Attribute accuracy is described, where present, with each
           attribute defined in the Entity and Attribute Section.


Logical_Consistency_Report: Polygon and chain-node topology present.


Completeness_Report
This data set includes aquifer information for the 48 contiguous
United States.
 
 
Positional_Accuracy 
    Horizontal_Positional_Accuracy
        Horizontal_Positional_Accuracy_Report:
        not available
         
         




    Vertical_Positional_Accuracy
        Vertical_Positional_Accuracy_Report:
        not available
         
         
Lineage: See Supplemental_Information for overview.


Process_Steps

Cloud_Cover
 
 

Spatial_Data_Organization_Information
Direct_Spatial_Reference_Method: Vector


Point_and_Vector_Object_Information
    SDTS_Terms_Description
        SDTS_Point_and_Vector_Object_Type: Point
        Point_and_Vector_Object_Count: 4350
        SDTS_Point_and_Vector_Object_Type: String
        Point_and_Vector_Object_Count: 7128
        SDTS_Point_and_Vector_Object_Type: GT-polygon composed of chains'
        Point_and_Vector_Object_Count:  4351



Spatial_Reference_Information 
Horizontal_Coordinate_System_Definition 
    Projection:  Unknown



Entity_and_Attribute_Information 
Detailed_Description 
    Entity_Type
    Entity_Type_Label: US_AQUIFERS.PAT
    Entity_Type_Definition: aquifers iformation explanation
    Entity_Type_Definition_Source: ARC/INFO
    Attribute:
        Attribute_Label: -
        Attribute_Definition: aquifers iformation explanation
        Attribute_Definition_Source: ARC/INFO
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: -
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: AREA
        Attribute_Definition: Area of poly/region in square coverage units
        Attribute_Definition_Source: Computed
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: Positive real numbers
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: PERIMETER
        Attribute_Definition: Perimeter of poly/region in coverage units
        Attribute_Definition_Source: Computed
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: Positive real numbers
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: US_AQUIFERS#
        Attribute_Definition: Internal feature number
        Attribute_Definition_Source: Computed
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: Sequential unique positive integer
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: US_AQUIFERS-ID
        Attribute_Definition: User-assigned feature number
        Attribute_Definition_Source: User-defined
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: Integer
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: POLY#
        Attribute_Definition: 
        Attribute_Definition_Source: 
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: 
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: SUBCLASS
        Attribute_Definition: 
        Attribute_Definition_Source: 
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: 
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: SUBCLASS#
        Attribute_Definition: 
        Attribute_Definition_Source: 
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: 
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: RINGS_OK
        Attribute_Definition: 
        Attribute_Definition_Source: 
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: 
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: RINGS_NOK
        Attribute_Definition: 
        Attribute_Definition_Source: 
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: 
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: AQUIFRP020
        Attribute_Definition: 
        Attribute_Definition_Source: 
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: 
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: AQUIFRP020A
        Attribute_Definition: 
        Attribute_Definition_Source: 
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: 
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: ROCK_NAME
        Attribute_Definition: The name of the permeable geologic material that composes the aquifer
        Attribute_Definition_Source: 
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: 
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: ROCK_TYPE
        Attribute_Definition: The code number relating to the rock_name.
        Attribute_Definition_Source: 
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: 
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: AQ_NAME
        Attribute_Definition: The aquifer unit name
        Attribute_Definition_Source: U.S. Geological Survey
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: 
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: AQ_CODE
        Attribute_Definition: The code number relating to the aquifer unit name
        Attribute_Definition_Source: 
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: 
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Entity_Type
    Entity_Type_Label: US_AQUIFERS.AAT
    Entity_Type_Definition: Aquifer boundaries and internal contacts
    Entity_Type_Definition_Source: ARC/INFO
    Attribute:
        Attribute_Label: -
        Attribute_Definition: Aquifer boundaries and internal contacts
        Attribute_Definition_Source: ARC/INFO
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: -
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: FNODE#
        Attribute_Definition: Internal number of from-node
        Attribute_Definition_Source: Computed
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: Sequential unique positive integer
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: TNODE#
        Attribute_Definition: Internal number of to-node
        Attribute_Definition_Source: Computed
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: Sequential unique positive integer
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: LPOLY#
        Attribute_Definition: Internal number of poly to left of arc
        Attribute_Definition_Source: Computed
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: Sequential unique positive integer
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: RPOLY#
        Attribute_Definition: Internal number of poly to right of arc
        Attribute_Definition_Source: Computed
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: Sequential unique positive integer
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: LENGTH
        Attribute_Definition: Length of arc in coverage units
        Attribute_Definition_Source: Computed
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: Positive real numbers
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: US_AQUIFERS#
        Attribute_Definition: Internal feature number
        Attribute_Definition_Source: Computed
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: Sequential unique positive integer
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:
    Attribute:
        Attribute_Label: US_AQUIFERS-ID
        Attribute_Definition: User-assigned feature number
        Attribute_Definition_Source: User-defined
        Attribute_Domain_Values
            Enumerated_Domain
                Enumerated_Domain_Value: Integer
                Enumerated_Domain_Value_Definition
                Enumerated_Domain_Value_Definition_Source:


 Overview_Description 
    Entity_and_Attribute_Overview 
     
    COLUMN   ITEM NAME        WIDTH OUTPUT  TYPE N.DEC
    1  AREA                   4    12     F      3
    5  PERIMETER              4    12     F      3
    9  US_AQUIFERS#           4     5     B      -
    13  US_AQUIFERS-ID         4     5     B      -
    17  POLY#                  4     5     B      -
    21  SUBCLASS              13    13     C      -
    34  SUBCLASS#              4     5     B      -
    38  RINGS_OK               7     7     I      -
    45  RINGS_NOK              7     7     I      -
    52  AQUIFRP020             8    11     F      0
    60  AQUIFRP020A            8    11     F      0
    68  ROCK_NAME             45    45     C      -
    113  ROCK_TYPE              4     5     B      -
    117  AQ_NAME               65    65     C      -
    182  AQ_CODE                4     5     B      -
     
    Several attributes were duplicated when this coverage was converted
    from a shapefile to an ARC/INFO coverage. Including, POLY#, SUBCLASS,
    SUBCLASS#, RINGS_OK, RINGS_NOK, AQUIFRP020, and AQUIFRP020A.
     
     
    There is no predefined set of official aquifer names. The names used
    in this data set are listed below. There should be a direct
    correlation between the values of the rock_type and rock_name
    attributes, and between the aq_name and aq_code attributes. The
    aq_names are as follows:
     
    aq_code -- aq_name
    0   -- null value, assigned to null polygon
    101  -- Basin and Range aquifers
    102 -- Rio Grande aquifer system
    103 -- California Coastal Basin aquifers
    104 -- Pacific Northwest basin-fill aquifers
    105 -- Northern Rocky Mountains Intermontane Basins aquifer system
    106 -- Central Valley aquifer system
    107 -- High Plains aquifer
    108 -- Pecos River Basin alluvial aquifer
    109 -- Mississippi River Valley alluvial aquifer
    110 -- Seymour aquifer
    111 -- Surficial aquifer system
    112 -- Puget-Willamette Lowland aquifer system
    201 -- Coastal lowlands aquifer system
    202 -- Texas coastal uplands aquifer system
    203 -- Mississippi embayment aquifer system
    204 -- Southeastern Coastal Plain aquifer system
    205 -- Northern Atlantic Coastal Plain aquifer system
    301 -- Colorado Plateaus aquifers
    302 -- Denver Basin aquifer system
    304 -- Lower Cretaceous aquifers
    305 -- Rush Springs aquifer
    306 -- Central Oklahoma aquifer
    307 -- Ada-Vamoosa aquifer
    308 -- Early Mesozoic basin aquifers
    309 -- New York sandstone aquifers
    310 -- Pennsylvanian aquifers
    311 -- Mississippian aquifer of Michigan
    312 -- Cambrian-Ordovician aquifer system
    313 -- Jacobsville aquifer
    314 -- Lower Tertiary aquifers
    315 -- Upper Cretaceous aquifers
    316 -- Wyoming Tertiary aquifers
    401 -- Basin and Range carbonate-rock aquifers
    402 -- Roswell Basin aquifer system
    405 -- Ozark Plateaus aquifer system
    406 -- Blaine aquifer
    407 -- Arbuckle-Simpson aquifer
    410 -- Silurian-Devonian aquifers
    411 -- Ordovician aquifers
    412 -- Upper carbonate aquifer
    413 -- Floridan aquifer system
    414 -- Biscayne aquifer
    416 -- New York and New England carbonate-rock aquifers
    417 -- Piedmont and Blue Ridge carbonate-rock aquifers
    418 -- Castle Hayne aquifer
    501 -- Edwards-Trinity aquifer system
    502 -- Valley and Ridge aquifers
    503 -- Mississippian aquifers
    504 -- Paleozoic aquifers
    505 -- Valley and Ridge carbonate-rock aquifers
    601 -- Southern Nevada volcanic-rock aquifers
    602 -- Northern California volcanic-rock aquifers
    603 -- Pliocene and younger basaltic-rock aquifers
    604 -- Miocene basaltic-rock aquifers
    605 -- Volcanic-and sedimentary-rock aquifers
    606 -- Snake River Plain aquifer system
    607 -- Columbia Plateau aquifer system
    999 -- Not a principal aquifer (field left blank).  Rocks that are
    generally poorly permeable but locally may contain productive
    aquifers.
     
     
    Entity_and_Attribute_Detail_Citation: Not Available



Distribution_Information 
Metadata_Reference_Section
Metadata_Date: 19991214
Metadata_Contact:
 
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version:  19940608
Metadata_Time_Convention:  Local Time
Metadata_Security_Information:
    Metadata_Security_Classification_System:  None
    Metadata_Security_Classification:  UNCLASSIFIED
    Metadata_Security_Handling_Description:  None


Last modified: 99-12-14.14:51:10.Tue