[Keyword='Geographic Information Systems']
Bedrock Valleys of IllinoisEntry ID: IGDNR_ALLST_BEDVAL
Abstract: This data set 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
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.
Data Set Citation
Dataset Originator/Creator: Illinois State Geological Survey
Dataset Title: Bedrock Valleys of Illinois
Dataset Series Name: ISGS GIS Database
Dataset Release Date: 1994
Dataset Release Place: Champaign, Illinois
Dataset Publisher: Illinois State Geological Survey
Issue Identification: bedval
Data Presentation Form: map
Start Date: 1994-01-01
ISO Topic Category
Access Constraints None
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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.
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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.
Data Set Progress
Distribution Media: Online
Distribution Size: 169KB
Distribution Format: Arc/Info export format
Fees: No fees
Role: DIF AUTHOR
Phone: (301) 614-6898
Email: Tyler.B.Stevens at nasa.gov
NASA Goddard Space Flight Center Global Change Master Directory
Province or State: MD
Postal Code: 20771
Role: TECHNICAL CONTACT
Email: stiff at geoserv.isgs.uiuc.edu
Illinois State Geological Survey 615 East Peabody Drive U.S.A.
Province or State: Illinois
Postal Code: 61820
Creation and Review Dates
DIF Creation Date: 2004-03-04
Last DIF Revision Date: 2009-03-26