Geologic Age: Identification Information

Originator:

United States Geological Survey (USGS)

Date:

June 29, 1999

Title:

Geologic Map (geo_join)

Purpose:

The purpose of digitizing the geologic map was to allow us to have a geologic base on which we drew the boundaries of the geologic provinces.

Abstract:

The World Energy Assessment created geologic maps of 7 regions. These regions were joined with minimum edge matching or checking for feature description by the Global GIS team. The user is warned there will be discrepancies on bordering features. The regions are described in the Geologic Provinces of the World full metadata files. Canada, Mexico and Central America, and the Europe tiles were screen digitized by the Global GIS team. These were approximately located and should be used as a geologic guide. The US and Alaskan Geologic Maps were kept as separate layers to allow the use the apply their original legends. See the ArcView help to apply these legends found in the the database\mapbase\i_lcov\geology directory. Please see the "Full Metadata Link" above for more information on errors for each area.

Access Constraints:

none

Use Constraints:

Portions of this database covering coastline and country boundaries contain intellectual property of Environmental Systems Research Institute, Inc. (ESRI), and are used with their permission. End users are permitted to use these data sets for their own internal use, including derivative work, but are prohibited from using and redistributing these data individually or in a derivative work to third parties.

Ordering Instructions:

none

Contact Address:

U.S. Geological Survey MS939, Box 25046

City:

Denver

State or Province:

Colorado

Postal Code:

80225-0046

Country:

USA

Online Linkage:

www.ccgm.org
www.unesco.org
energy.cr.usgs.gov/energy/WorldEnergy/WEnergy.html
webgis.wr.usgs.gov/globalgis
minerals.usgs.gov

Entity and Attribute Information
(table heading explanations)

Shape:

ArcView file type

Area (m^2):

Area of polygon

Glg:

Original Unit Class (abbreviated)

Desc:

Description of “Glg” code: (file: glg_code.dbf)

Period:

Major age type (Quaternary, Tertiary, Cretaceous ...)

Global GIS Note: These geologic layers (except the US and Alaskan maps) were blindly merged together. No edge matching was done and units were not check for consistency between each region. If this is a concern, please visit the web page above to access the original data in the original projection. We also added a field called "Period" to help make a generalized legend using the major age classifications (Quaternary, Tertiary, Cretaceous ...)