Named the Guymard quartzite for Guymard, near Otisville, Orange Co., NY. Name is attributed to a Professor van Ingen. Consists of over 100 ft of gray, olive, and reddish quartzite. The Guymard overlies the Shawangunk grit and underlies rocks characteristic of the Longwood shale. Unit is of Silurian age.
Source: GNU records (USGS DDS-6; Reston GNULEX).
Rocks previously called Guymard Quartzite are considered to be the contact interval between the Shawangunk Formation and the Wurtsboro Tongue of the Bloomsburg Red Beds. The red bed within this interval is placed in the Shawangunk. Since these rocks can bed placed within the Shawangunk and Bloomsburg, the Guymard is abandoned.
Source: GNU records (USGS DDS-6; Reston GNULEX).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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