National Geologic Map Database
Geologic Unit: Kassler
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Map showing publication footprint
  • Usage in publication:
    • Kassler sandstone member*
  • Modifications:
    • Named
  • Dominant lithology:
    • Sandstone
  • AAPG geologic province:
    • Denver basin

Waage, K.M., 1955, Dakota group in northern Front Range foothills, Colorado, IN Shorter contributions to general geology, 1955-57: U.S. Geological Survey Professional Paper, 274-B, p. B15-B51. [Available online from the USGS PubsWarehouse: http://pubs.er.usgs.gov/pubs/pp/pp274B]


Named as a middle member of South Platte formation of Dakota group for exposures near Kassler in Kassler quad, Jefferson Co, CO in the Denver basin. Type section measured at end of hogback 0.5 m north of the South Platte River at Kassler, also the type section of the South Platte. Is composed of fine-, medium- and coarse-grained sandstone. Is thin bedded to massive, and cross bedded. Some beds are friable. Weathers gray. Is 71.8 ft thick at type where it unconformably overlies an unnamed siltstone and shale and underlies disconformably? the Van Bibber shale member of the South Platte. Is a ledge-forming sandstone 75 to 100 ft thick in the quad. Is a nonmarine unit assigned an Early Cretaceous age. Correlation with other Cretaceous units in Powder River basin in northeast WY, Wind River basin in central WY and Denver basin, southeast WY, northeast and south-central CO shown on fig 19.

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

For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.

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