• Specimen Number

  25

• Description

  Disintegrating block of weak, porous sandstone. Identified by the state survey staff at University of Nebraska Lincoln as a "calcareous sandstone from the Ogallala Group."  Such "caliche" cemented sandstones form the caprock of many local buttes.

• Classification

  Sedimentary. Sandstone. Calcareous.

• Location & Occurrence

  Fluvial clastic wedge of river sediment draining eastward from the rising Cordillera.  Underlies much of the high plains.  Staff of the state survey said it could be from nearly anywhere in the state.

• Geologic Age

  Miocene to Pliocene.

• Geoheritage

  The Ogalalla aquifer is (or was) one of our nation's most important natural resources, an enormous underground reservoir of fresh water within this formation is named for a locality in Nebraska.

• Links

  Link to State Geological Map from USGS.  Link to Nebraska Geological Survey.

• Other

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