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Stillwater Complex, Montana: Logs of core drilled by Cyprus in the Chrome Lake area, 1971 to 1980

June 24, 2021

This dataset includes TIFF (Tagged Image File Format) images of graphic drill core logs showing associated drill core information, a TIFF image of the explanation for the lithology and structure sections of the logs, an Esri shapefile of the locations of the drill holes, and fourteen individual .csv files of tabular data that were compiled from handwritten drill core logs. The drill core is from the Stillwater Complex, Montana and was drilled from 1971 to 1980 by the Cyprus Mines Corporation. The core was logged in 1986. The data shown in the graphic drill logs and contained within the .csv files includes lithologic, structure, core recovery, grain size, chromite, sulfide, copper, and nickel mineralization information. The graphic drill logs were created using Golden software's Strater 5 drill core visualization software and are provided with both logarithmic and linear scales. See USGS SIR 2014-5183 ( for report and spatial data relating to the Stillwater Complex.