Illinois State Geological Survey 1994 20040331 vector digital data ISGS GIS Database GISDB_BEDGEO.IL_Bedrock_Valleys Champaign, Illinois Illinois State Geological Survey The map scale is 1:500,000 http://www.isgs.illinois.edu/ http://illinois.edu This feature dataset shows continuous lines representing the lowermost elevations/locations of (buried) bedrock valleys in the state of Illinois. Additionally, names of buried valleys are annotated. Scale is 1:500,000. Several major bedrock valleys are found across the state. The greatest control for the present bedrock surface configuration was probably the preglacial surface configuration. Interpretations of bedrock topography have been modified since the 1950's. Horberg contoured his map with the philosophy that the bedrock surface map represented the preglacial topography modified by glacial erosion, which formed U-shaped valleys. The current map, showing narrow valley channels and bedrock knobs in wide channels, indicates complex preglacial and glacial erosion primarily from running water. The major valleys were formed before the minor valleys that appear as tributaries. Streams that formed during successive glaciations probably eroded to bedrock and produced the small tributary valleys to the main channels. The bedrock surface was less likely to be eroded as sediments accumulated during each successive glaciation. Please refer to the metadata for the parent coverage, Buried Bedrock Surface of Illinois (GISDB_BEDGEO.IL_Bedrock_Topography_1994_Ln) for more information. Applications are regional or statewide studies, preferably at a scale of 1:500,000. Bedrock valley data can be used in conjunction with the buried bedrock surface information, which will be useful in such fields as groundwater resource planning, engineering geology and earthquake hazard mapping. The data are not appropriate as a geodetic, legal or engineering base. The data set was not and is not intended as a substitute for surveyed locations, such as can be determined by a registered Public Land Surveyor. Although useful in a GIS as a reference base layer for maps, the data set has no legal basis in the definition of boundaries or property lines. A version of this is also housed on optical disk as bedval-2. Recent updates to the data: In March 2004 edition 1.0 of the data set was transitioned to storage in an Oracle RDBMS using the ArcSDE geodatabase model. The result (this version) is designated Edition 20040331. 1994 publication dates of digital sources Complete None planned -91.5826823 -87.38401652 42.49563968 36.95351896 none geology bedrock valley Illinois basin none Illinois none Tertiary Cretaceous Pennsylvanian Mississippian Devonian Silurian Ordovician Cambrian ISGS information must be obtained directly from the ISGS or from an authorized distributor. Be aware that ISGS information obtained from an unauthorized third party may have been altered subsequent to original distribution, or may no longer be current. Any access to these data, Web sites, computer systems, electronic services, and electronic networks is governed by University and campus policies, in particular, but not limited to, the Policy on Appropriate Use of Computers and Network Systems at the University of Illinois at Urbana-Champaign, the ISGS Terms of Use document available at the ISGS Web site, and the University of Illinois Web Privacy Notice. Links to these are provided in the Cross References section. ISGS information is the property of and copyrighted by the Board of Trustees of the University of Illinois with all rights reserved.  University copyright policy is stated in the General Rules Concerning University Organization and Procedure, Article III, Section 4. A link is provided in the Cross References section. Individuals or entities may make fair use of copyrighted ISGS material, such as reproducing a single figure or table, or using a brief text quotation, without obtaining formal permission, but in all cases the Illinois State Geological Survey must be credited as the source of the material. To reproduce ISGS information beyond the fair use standard, permission must be obtained from the ISGS Information Office, 615 East Peabody Drive, Champaign, Illinois 61820, 217-333-4747, isgs@isgs.illinois.edu. License fees and a license agreement may be required, depending on the proposed usage. Any use of these data is governed by University and campus policies, in particular, but not limited to, the Policy on Appropriate Use of Computers and Network Systems at the University of Illinois at Urbana-Champaign, the ISGS Terms of Use document available at the ISGS Web site, and the University of Illinois Web Privacy Notice. Links to these are provided in the Cross References section. Map information is to be used at a scientifically and cartographically appropriate scale, that is, at a scale no greater than indicated on the map or as described in the documentation of the map or map data.  Map information is not appropriate for, and is not to be used as, a geodetic, legal, or engineering base. Map information has no legal basis in the definition of boundaries or property lines and is not intended as a substitute for surveyed locations such as can be determined by a registered Public Land Surveyor. The data do not replace the need for detailed site-specific studies. Please refer to the Distribution Information section. ArcSDE 9.1 on Oracle 10g http://www.isgs.illinois.edu http://www.vpaa.uillinois.edu/policies/web_privacy.cfm http://www.uillinois.edu/trustees/rules.cfm#sec34 http://www.fs.uiuc.edu/cam/CAM/viii/viii-1.1.html The published geological map (ISGS Illinois Map 5, 1994) was the source for updated feature attributes. Attribute code assignments were reviewed by both the ISGS and the USGS and are believed to be fully representative of the source document. When in coverage format, this data set was checked for complete chain-node topology (no dangling arcs, except where appropriate), boundary values appropriate for map projection and map units, and appropriate "fuzzy" tolerances. This data set depicts the buried bedrock valleys of Illinois. Only major valleys are included. Although this version has updated the major valleys since Horberg (1950), that source also shows smaller-scale tributary valleys which are not included in this dataset. Horizontal positional accuracy of this data with respect to the source map was verified by ISGS and USGS personnel by visual comparison (manual overlay) of source mylars and hard-copy plots. Arcs within one line-width of source mylars were deemed acceptable. Herzog, B.L.. B.J. Stiff, C.A. Chenoweth, K.L. Warner, J.B. Sievering, C. Avery 1994 map ISGS GIS Database GISDB_BEDGEO.IL_Bedrock_Topography_1994_Ln Champaign, Illinois Illinois State Geological Survey Scale is 1:500,000. This is the digital version of ISGS Map Series, Illinois Map 5. 500000 online 1994 publication date none linework and attributes Herzog, B.L., B.J. Stiff, C.A. Chenoweth, K.L. Warner, J.B. Sievering, C. Avery 1994 map ISGS Illinois Map Series 5 Champaign, Illinois Illinois State Geological Survey 500000 paper 1994 publication date none contour attributes (elevation values) Herzog, B.L.. B.J. Stiff, C.A. Chenoweth, K.L. Warner, J.B. Sievering, C. Avery 1994 map Champaign, Illinois Illinois State Geological Survey unpublished material 500000 stable-base material 1994 publication date none contour lines Horberg, L. 1950 report ISGS Bulletin 73 Champaign, Illinois Illinois State Geological Survey not available paper 1950 publication date none not available Initial information was digitized from ISGS Bulletin 73. Unknown Updates to information were made corresponding to the creation of ISGS Illinois Map Series Plate 5. Refer to Process Step Entries for GISDB_BEDGEO.IL_Bedrock_Topography_1994_Ln for detailed information about creation of the source data set. 1994 The source coverage data for the feature classes were reprojected from the customary ISGS Lambert projection, NAD27 to geographic coordinates, NAD83, double-precision. The line features were imported into the ISGS SDE enterprise database, following steps outlined in ISGS procedure GISDB_0009. The source coverage was bedval. The annotation feature class was imported into SDE from the source coverage using the method in an article entitled Converting Annotation from Coverage to Geodatabase Format (Colin Childs, ArcUser Magazine, October-December 2001, pp. 22-23) and the companion tutorial (referenced in the article.) Prior to using the steps in the tutorial, a TAT coverage file had to be generated for the coverage. This was done in ArcInfo Workstation 7.2.1 with the following commands. Arc: copyfeatures bedval anno bedval anno.anno Arc: build bedval annotation.anno 20040331 13395200 Vector String 55 G-polygon 32 0.000001 0.000001 Decimal degrees North American Datum of 1983 Geodetic Reference System 80 6378137.000000 298.257222 GISDB_BEDGEO.IL_Bedrock_Valleys_Ln GISDB_BEDGEO.IL_Bedrock_Valleys_An File attribute items are in typical SDE feature class format. The following arc items require additional explanation: NAME - name of bedrock valley 1 - ancient Mississippi (Lower and Middle Illinois and Princeton) 2 - Mahomet (Teays) 3 - Kaskaskia 4 - Paw Paw and Rook 5 - Troy 6 - Pecatonica 7 - Onarga 8 - Little Wabash 9 - Embarras 10 - Skillet Fork 11 - Saline 12 - Big Muddy 13 - Macoupin 14 - Cache 200 - Carthage, Lower Spoon, Ticona, Danvers, Middletown, Pesotum, Danville 300 - Kempton and Chatsworth 400 - Kirkwood, Athens, Wyoming, plus four unnamed tributary channels (Pecatonica [2], Rook [1], Danville [1]) 999 - state boundary Annotation features are included to display the bedrock valley name. none Information Office, Illinois State Geological Survey (ISGS), a division of the Institute of Natural Resource Sustainability (INRS) of the University of Illinois mailing and physical address

615 East Peabody Drive

Champaign Illinois 61820 USA 217-333-4747 217-785-0211 isgs@isgs.illinois.edu 8:00 a.m. - 4:30 p.m., Monday-Friday, U.S. Central Time Refer to the Legal Notices of Terms and Conditions of the University of Illinois Web Privacy Policy (there is a link in the Cross References section) for policy statements regarding the following: Disclaimer of Liability Disclaimer of Warranties and Accuracy of Data Disclaimer of Endorsement Disclaimer for External Links Disclaimer of Duty to Continue Provision of Data Security Choice of Law By obtaining these data you agree to the provisions of the University of Illinois Web Privacy Policy, regardless of the manner in which the information was obtained. The data are intended for use with GIS software. The ISGS uses ESRI ArcGIS software, however, ESRI formats can be imported into many different GIS software packages. It is expected that customers who obtain these data have the technical expertise to use GIS software. The ISGS does not provide software support of any kind. 20090224 Please refer to the Distribution Information section. FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998 local time The access constraints as stated for the data apply also to the metadata. Refer to the Access Constraints section of the Identification Information section. The use constraints as stated for the data apply also to the metadata. Refer to the Use Constraints section of the Identification Information section. http://www.esri.com/metadata/esriprof80.html ESRI Metadata Profile