The informal Tower Hill quartzite member of the Boylston Formation of Grew (1970), also called unit B of Grew (1973), is here named the Tower Hill Quartzite of the Merrimack Group in the Worcester area, MA. It consists of orthoquartzite with interlayered pelite and may represent a proximal facies laterally equivalent to the distal facies of the Worcester Formation. Overlies the Boylston Schist and underlies the Oakdale Formation. Age is probably Silurian based on a tentative correlation with rocks in central Maine.
Source: GNU records (USGS DDS-6; Reston GNULEX).
Used as Tower Hill Quartzite of Silurian age. Merrimack Group assignment not used.
Source: GNU records (USGS DDS-6; Reston GNULEX).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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