Introduction
This report describes a digital map and data files generated by the U.S. Geological Survey
(USGS) to provide digital spatial mining claim information for Federal lands in Montana as of
March, 1997. Statewide, 159,704 claims had been recorded with the Bureau of Land
Management since 1975. Of those claims, 21,055 (13%) are still actively held while 138,649
(87%) are closed and are no longer held. Montana contains 147,704 sections (usually 1 section
equals 1 square mile) in the Public Land Survey System, with 8,569 sections (6%) containing
claim data. Of the sections with claim data, 2,192 (26%) contain actively held claims. Only 1.5%
of Montana’s sections contains actively held mining claims. The four types of mining claim are
lode, placer, mill, and tunnel. A mill claim may be as much as 5 acres or 1/128th (0.78125%) of a
square mile. A lode claim, about 20 acres, would cover 1/32nd (3.125%) of a square mile.
Mining claim data is earth science information deemed to be relevant to the assessment of
historic, current, and future ecological, economic, and social systems. The digital map
and data files that are available in this report are suitable for geographic information system
(GIS)-based regional assessments at a scale of 1:100,000 or smaller.
Campbell (1996) summarized the methodology and GIS techniques that were used to produce
the mining claim density map of the Pacific Northwest. Campbell and Hyndman (1997) displayed
mining claim information for the Pacific Northwest that used data acquired in 1994. Appendix A
of this report lists the attribute data for the digital data files. Appendix B contains the GIS
metadata.
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First posted April 9, 2001
- Map files TAR.Z (4.1 MB)
HPGL2, EPS, and GRA format as an UNIX compressed (and, in some cases, TAR) file. Map scale: 1:500,000
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