Named for Cold Spring Park, Baltimore City, Baltimore Co., east-central MD. Consists of biotite-muscovite-quartz-feldspar gneiss or schistose gneiss. Intrudes Hollofield Layered Ultramafite and Mount Washington Amphibolite (Baltimore Mafic Complex), and Druid Hill Amphibolite Member of James Run Formation. Age is Ordovician(?) or Silurian(?).
Source: GNU records (USGS DDS-6; Reston GNULEX).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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