Poquoson Member of Tabb Formation (new name) here named in southeastern VA. Beach and nearshore marine and fluvial-estuarine deposits described as gray, and yellowish-brown silty, clayey, and gravelly sand. Poquoson is uppermost member and underlies Holocene deposits. Unconformably overlies Lynnhaven and Sedgefield Members (new names), or Norfolk or Yorktown Formations. 3.31 m thick. Age is late Pleistocene.
Source: GNU records (USGS DDS-6; Reston GNULEX).
Late Pleistocene Tabb Formation and its three subdivisions, Sedgefield, Lynnhaven, and Poquoson Members, mapped west and south of Chesapeake Bay in the Virginia Coastal Plain. Tabb Formation overlies middle Pleistocene Shirley Formation.
Source: GNU records (USGS DDS-6; Reston GNULEX).
Nomenclature on State map follows Johnson (1976). Poquoson is upper member of Tabb Formation. Unit is medium to coarse pebbly sand grading upward into clayey fine sand and silt, light- to medium-gray; underlies ridge and swale topography (altitude ranges from sea level to 11 ft) along the margin of Chesapeake Bay and in the lower and middle parts of Coastal Plain rivers. Thickness is 0 to 15 ft. Overlies Lynnhaven Member. Age is late Pleistocene.
Source: GNU records (USGS DDS-6; Reston GNULEX).
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