Illinois Geographic Information System, 199803, Index of US Geological Survey 15 Minute Quadrangle Map Series for Illinois: ISGS GIS Database quad15, Illinois State Geological Survey, Champaign, Illinois.Online Links:
- Downloadable Data (Shift-Click to download data file) <URL:http://www.isgs.uiuc.edu/nsdihome/browse/statewide/quad15.e00>
- Browse Graphic (GIF) Screen-size image representing the nature of the data. <URL:http://www.isgs.uiuc.edu/nsdihome/browse/statewide/quad15b.gif>
- Text (.txt) version of this Metadata file. (Shift-Click to download documentation) <URL:http://www.isgs.uiuc.edu/nsdihome/outmeta/quad15.txt>
- HTML (.html) version of this Metadata file. (Shift-Click to download documentation) <URL:http://www.isgs.uiuc.edu/nsdihome/outmeta/quad15.html>
This is a Vector data set. It contains the following vector data types (SDTS terminology):
The map projection used is Lambert Conformal Conic.
Planar coordinates are encoded using coordinate pair
Abscissae (x-coordinates) are specified to the nearest unknown
Ordinates (y-coordinates) are specified to the nearest unknown
Planar coordinates are specified in feet
The horizontal datum used is NAD27.
The ellipsoid used is CLARKE1866.
The semi-major axis of the ellipsoid used is 6378206.4 meters.
The flattening of the ellipsoid used is 1/294.98.
Attribute items are in typical ARC/INFO feature class format.
Those requiring additional explanation are:
POLYGON ATTRIBUTES:
MAPNAME - Name of the associated USGS 30' x 60' quadrangle
USGS - USGS map sheet index designation. This is an alphanumeric
combination of degrees north and west with a row column
index applied to each 1 degree by 1 degree area.
ARC ATTRIBUTES:
COORD - The latitude value for east-west arcs or the longitude
value for north-south arcs. Values are in decimal degrees.
COORD is redefined into two smaller fields:
INTEGER - The value of COORD to the left of the decimal.
(The value of COORD rounded down to a whole number.)
DECIMAL - The value of COORD to the right of the decimal.
(The incremental fraction of COORD.)
Q100 - Indicates if arc is also a boundary for a 30' x 60' quad.
0 - arc is not a 30' x 60' quad boundary
2 - arc is a 30' x 60' quad boundary
Q75 - Indicates if arc is also a boundary for a 7.5 minute quad.
0 - arc is not a 7.5 minute quad boundary
2 - arc is a 7.5 minute quad boundary
Q250 - Indicates if arc is also a boundary for a 1 x 2 degree quad.
0 - arc is not a 1 x 2 degree quad boundary
2 - arc is a 1 x 2 degree quad boundary
ANNOTATION ATTRIBUTES:
Each quad is annotated with the quad name.
GIS Processing: B. Stiff, D. Nelson Documentation: D. Nelson and S. Beaverson Quality Control: ISGS Staff, D. Nelson
217-333-4747 (voice)
217-244-0802 (FAX)
isgs@isgs.uiuc.edu
This data set was created to serve as base map information. Data are appropriate for use at a regional scale and are intended as a reference. Data are not appropriate as a geodetic or engineering base.
Illinois State Geological Survey, 199803, Quadrangle Template: 7.5' Arcs From 36 To 43 Degrees North Latitude And 87 To 92 West Longitude: ISGS GIS Database quadtile, Illinois State Geological Survey, Champaign, Illinois.Online Links:
- Data Set Documentation <URL:http://www.isgs.uiuc.edu/nsdihome/outmeta/quadtile.html>
Illinois Geographic Information System, 199403, 199803, Index of US Geological Survey 30 x 60 Minute Quadrangle Map Series for Illinois: IGIS GIS Database quad100, Illinois Geographic Information System, Champaign, Illinois.Online Links:
- Data Set Documentation <URL:http://www.isgs.uiuc.edu/nsdihome/outmeta/quad100.html>
Illinois State Geological Survey, 199210, 199803, Index of US Geological Survey 7.5 Minute Quadrangle Map Series for Illinois: ISGS GIS Database quad75, Illinois State Geological Survey, Champaign, Illinois.Online Links:
- Data Set Documentation <URL:http://www.isgs.uiuc.edu/nsdihome/outmeta/quad75.html>
Illinois Geographic Information System, 199403, 199803, Index of US Geological Survey 1 x 2 Degree Quadrangle Map Series for Illinois: IGIS GIS Database quad250, Illinois Geographic Information System, Champaign, Illinois.Online Links:
- Data Set Documentation <URL:http://www.isgs.uiuc.edu/nsdihome/outmeta/quad250.html>
No formal review has been completed. Regular use of these data, however, indicate attributes are accurate. Two arcs in the Chicago region form the eastern boundaries of two irregularly shaped quadrangles. These have a value of 999.999 in .AAT item COORD.
These data are a mathematical construct and as such should have a high degree of positional accuracy. No review has been completed, however. There have been several instances where these boundaries have been used with other data digitized from USGS quadrangles with good results.
All quadrangles that intersect the state of Illinois are included. Several of the quadrangles on the state border, however, have modified boundaries. The boundaries have been modified so that the spatial extent of the polygon includes only those 7.5 minute quadrangles that intersect Illinois.
A logical consistency review was performed in March, 1998. The following checks were made:
Data set was DESCRIBED and coverage files listed to determine the feature types present. In this data set, the following feature types were found and checked: polygons, arcs, labels, nodes, and annotation. The presence of spatial indices was also checked.
For PAT and AAT files, each ITEM was checked for the following:
- DOMAIN of allowable values - adherence of values to the DOMAIN - definition of ITEMS - requirement of all UNIQUE values for an item - logic of ITEMS REDEFINED over other ITEMS - length of ITEM name as regards conversion to shape fileBUILD statuses of data sets were checked, as were LABELERRORS and NODEERRORS (where appropriate), and PROJECTION definition.
The presence of a BND file was verified.
The presence and location of TICS were checked.
Polygon and chain-node topology present. There are no dangling arcs. There is one polygon label per polygon, except for universe polygon. Boundary values appropriate for map projection and map units. "Fuzzy" tolerance is suitable for nominal scale. Two arcs in the Chicago region form the eastern boundaries of two irregularly shaped quadrangles. These have a value of 999.999 in .AAT item COORD. There are no attribute values outside the appropriate domains.
Are there legal restrictions on access or use of the data?
- Access_Constraints: none
- Use_Constraints:
- Reproduction or redistribution of copyrighted digital data sets or products derived therefrom outside of licensee's organization or entity is expressly forbidden. The only exception is redistribution to consultants working for the licensee, and then only for purposes, related to work for the licensee. Such consultants may not further reproduce or redistribute these data sets. None of these data shall be electronically duplicated on magnetic or optical media for use by others, in whole or in part, without permission of the appropriate custodial division within DNR.
Any hardcopies utilizing DNR data sets shall clearly indicate their source. If the licensee has modified the data in any way they are obligated to describe the types of modifications they have performed on the hardcopy map. Licensee specifically agrees not to misrepresent DNR data sets, nor to imply that changes they made were approved by DNR.
These data are not to be used for commercial profit.
217-333-4747 (voice)
217-244-0802 (FAX)
isgs@isgs.uiuc.edu
An Arc/Info .e00 (export) file is currently available free of charge at the Illinois Natural Resources Geospatial Data Clearinghouse. Refer to the Citation Information portion of this file for access to downloadable data and metadata, and a visual (GIF image) representation of the data. Shift-click to download the data set and related documentation. (Data and metadata offered separately, please download both files.)
The Illinois Department of Natural Resources (DNR) provides these geographic data "as is." DNR makes no guarantee or warranty concerning the accuracy of information contained in the geographic data. DNR further makes no warranties, either expressed or implied as to any other matter whatsoever, including, without limitation, the condition of the product, or its fitness for any particular purpose. The burden for determining fitness for use lies entirely with the user. Although these data have been processed successfully on computers of DNR, no warranty, expressed or implied, is made by DNR regarding the use of these data on any other system, nor does the fact of distribution constitute or imply any such warranty.In no event shall the DNR have any liability whatsoever for payment of any consequential, incidental, indirect, special, or tort damages of any kind, including, but not limited to, any loss of profits arising out of use of or reliance on the geographic data or arising out of the delivery, installation, operation, or support by DNR.
217-333-4747 (voice)
217-244-0802 (FAX)
isgs@isgs.uiuc.edu
Illinois Natural Resources Geospatial Data Clearinghouse
Generated by mp version 2.8.11 on Mon Jan 29 15:19:41 2007