A series of volcanic cones piled on top of one another lie in Sugarloaf Arkose north of Mount Hitchcock. Underlies Holyoke lava. Thickness is 1,000 ft (300 m).
Source: GNU records (USGS DDS-6; Reston GNULEX).
Volcanics near Mount Hitchcock, east of Mount Holyoke, are here named Hitchcock Volcanics.
Source: GNU records (USGS DDS-6; Reston GNULEX).
Used as Hitchcock Volcanics of Early Jurassic age. Consists of nested cones of basaltic breccia containing abundant fragments of New Haven Arkose, locally intrusive into arkose near its base. Overlain by Holyoke Basalt and (or) Shuttle Meadow Formation. [No explanation given for age change.]
Source: GNU records (USGS DDS-6; Reston GNULEX).
The use of the name Hitchcock Volcanics follows that of Brophy and others (1967) and is assigned to the Newark Supergroup. It consists of nested cones of basaltic breccia containing abundant fragments of New Haven Arkose, locally intrusive into arkose near the base. It underlies the Shuttle Meadow Formation and (or) the Holyoke Basalt. Age is changed from Late Triassic to Early Jurassic.
Source: GNU records (USGS DDS-6; Reston GNULEX).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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