Purpose:
This project was designed to make the information about how much of Alaska is
mapped readily accessible. Types of geologic mapping and the level of detail vary widely among
geologic maps. This project is an attempt to classify the maps into different categories.
The map scale is generally, but not always, an indication of the level of detail included.
The information included in this project will be useful to mineral and energy exploration
companies, engineering firms, land planners, local, state, and federal government agencies,
Native Corporations, and many others. The project includes geographically registered map
outlines and basic citation information for geologic maps produced by government agencies.
Currently the interface contains maps only for
Alaska Division of Geological
& Geophysical Surveys, but maps by
U.S. Geological Surveys,
U.S. Bureau of Land Management,
and U.S. Bureau of Mines will be included in the future.
Funding:
This project was funded by the federal
Alaska Mineral Data At Risk (MDIRA) and
the Department of Natural Resources DGGS and LRIS.
Sources (for current data set):
Alaska Division of
Geological & Geophysical Surveys, and physical library, 3354 College Road,
Fairbanks, AK, 99709-9707.
Galloway, J.P., and Laney, Jim, 1994, Status of geologic mapping in Alaska-A digital
bibliography: U.S. Geological Survey Open-File Report 94-675-A, 96 p., 94-675-B
(IBM-compatible diskette), 94-675-C (Macintosh diskette).
Data Development Process:
Several of the authors corrected citation information and produced categories (themes) for the
geologic maps using actual publications and scanned publications. These data were stored in a
Microsoft Access database.
Note: The publications were categorized by several different people over a two-year period,
leading to some inconsistencies in classification. See
Categories for more information.
Map outlines were produced in MapInfo. Since the focus of the project to show what areas of
Alaska contained geologic maps and give an idea of how detailed the information was, care was
made to enter the actual area of mapping instead of the map sheet boundaries. In some cases,
this produces an outline that looks much different from the map sheet, but more accurately
reflects the true status of geologic knowledge. Map boundaries were input using a variety of
means including paper copies, registered scanned images, and selecting 1:250,000 or 1:63,360
quadrangle boundaries from a standard state coverage where appropriate.
A MapInfo "tab" file representing merged data for the DGGS Access and MapInfo data were
provided to DNR/LRIS. This information is served over the Internet using a MapInfo MapXtreme
Java application developed by DNR personnel.
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