Bradford Group. Informal drillers' term for Upper Devonian sands in subsurface of northwestern Pennsyvlania. Includes seven sand zones (ascending): (1) lower Kane; (2) Lewis Run; (3) Bradford Third / Richburg / Rushford / Alfred Station Coquinite; (4) Bradford Second / Cooper(?) / Scholes; (5) Clarendon / Chipmunk; (6) Queen / Glade / Bradford First /Cuba; and (7) Warren Second. Approximately equivalent to Canadaway Formation of New York. Underlies "Pink Rock" (C-shale zone) and overlies Venango Group. [Despite capitalization of rank term, author makes it clear that terminology is informal.]
Source: Modified from GNU records (USGS DDS-6; Reston GNULEX).
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