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National Geologic Map Database
Map showing publication footprint
  • Usage in publication:
    • Cabbage Patch beds
  • Modifications:
    • Overview
  • AAPG geologic province:
    • Montana folded belt
Publication:

Gwinn, V.E., 1961, Geologic map of the Drummond area, Granite and Powell Counties, Montana: Montana Bureau of Mines and Geology Geologic Map, no. 4, scale 1:63,360, Also issued as Montana Bur. Mines Geol. Spec. Pub., no. 21


Summary:

Underlies Flint Creek beds and is younger than the Golden Spike facies (new) of the Cretaceous Elkhorn Mountains Volcanics of latest Cretaceous age. Ranges from 0-500 ft thick in report area, Powell Co, MT, Montana folded belt province. Persists eastward into Gold Creek basin. Absent in eastern Flint Creek basin. Are 400-650 ft thick in Clark Fork valley. Of lacustrine and fluvial origin. Distinguished from overlying Flint Creek by predominance of massive bedding and by presence of feldspathic-micaceous conglomerate and sandstone. Of Tertiary age.

Source: GNU records (USGS DDS-6; Denver GNULEX).


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