• Specimen Number

  45

• Description

  Rough block of gray granodiorite. Identified by survey staff.  Filled fracture from lower right to upper left suggests contraction during cooling.

• Classification

  Igneous.  Plutonic. Granitic. Granodiorite.

• Location & Occurrence

  From the "State of Washington's new tunnel," as described in the 1937 Hartford Courant. Search indicates that the "New Cascade Tunnel" was a railroad tunnel through Stephen's Pass of the Cascades east of Seattle that was dedicated in 1930 as a great wonder, drawing national attention.  Formation name not known.   A Cascade Range batholith.

• Geologic Age

  Mesozoic

• Geoheritage

  Andes style arc magmatism.  The newspaper description provided the clue to where in the state it was from..

• Links

  USGS Compilation: Search for Washington in upper right.  Link to Washington Geological Survey.

• Other

  The Washington Geological Survey provides an example for the rest of the nation.

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