Montana geologic maps
Cartahaven has 3 geologic maps of Montana, all free. Georeferenced geologic maps from the U.S. Geological Survey: rock units, faults and structure.
Download one to your phone and the map app shows your GPS position on it with no cell signal.
Geologic map of the central Beaverhead Mountains, Lemhi County, Idaho, and Beaverhead County, Montana
USGS Scientific Investigations Map 3413
Geologic map of the Strawberry Butte 7.5’ quadrangle, Meagher County, Montana, sheet 1
USGS Scientific Investigations Map 3379
Surficial geology and Quaternary tectonics of the Madison Valley and fault zone, Madison, Gallatin, and Beaverhead Counties, southwest Montana, sheet 1
USGS Scientific Investigations Map 3508