Chromite deposits in central part Stillwater Complex, Sweet Grass County, Montana: A digital database for the geologic map of the east slope of Iron Mountain

In 1940, A.L. Howland and J. W. Peoples, assisted by W.R. Jones and M.G. Bennett, mapped the geology of the east slope of Iron Mountain, Montana. The map was revised and extended by Howland in 1942 and published in 1955 as plate 10 of the U.S. Geological Survey Bulletin 1015-D (Howland, 1955). In 2000, the USGS contracted Optronics Specialty Co., Inc. of Northridge, CA to prepare a scanned digital version of plate 10. Geospatial editing and attributing of the scanned map of the east slope of Iron Mountain was performed by the USGS in order to produce an interim digital product. This digital geospatial database is one of many being created by the U.S. Geological Survey as an ongoing effort to provide geologic information in a geographic information system (GIS) for use in spatial analysis.