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Geologic Units: Walston
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Map showing publication footprint
  • Usage in publication:
    • Walston Silt*
  • Modifications:
    • Named
  • Dominant lithology:
    • Silt
    • Sand
    • Clay
  • AAPG geologic province:
    • Atlantic Coast basin
Publication:

Rasmussen, W.C., and Slaughter, T.H., 1955, Geology and ground-water resources of Somerset, Wicomico, and Worcester Counties, Maryland: Maryland Geological Survey Bulletin, no. 16, 479 p.


Summary:

Walston Silt here named in southeastern MD. Occurs at the surface and in the subsurface. Described as a lenticular unit of sand, silty sand, sandy silt, silt, clayey silt, silty clay, and clay, with organic material. Thickness from a fraction of a foot to as much a 57 ft at reference locality in test hole north of Parsonsburg. Unconformably underlies Parsonsburg sand (new name) and unconformably overlies Beaverdam sand (new name). Age is considered Pleistocene (Yarmouth).

Source: GNU records (USGS DDS-6; Reston GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Walston Silt*
  • Modifications:
    • Areal extent
    • Age modified
  • AAPG geologic province:
    • Atlantic Coast basin
Publication:

Owens, J.P., and Denny, C.S., 1979, Upper Cenozoic deposits of the central Delmarva Peninsula, Maryland and Delaware, IN Surface and shallow subsurface geologic studies in the emerged coastal plain of the middle Atlantic states: U.S. Geological Survey Professional Paper, 1067-A, p. A1-A28. [Available online from the USGS PubsWarehouse: http://pubs.er.usgs.gov/pubs/pp/pp1067A]


Summary:

Walston Silt extended into DE. Age changed from Pleistocene to Pliocene. Underlies Omar Formation (Pleistocene) and overlies Beaverdam Sand (Pliocene).

Source: GNU records (USGS DDS-6; Reston GNULEX).


For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.

Asterisk (*) indicates published by U.S. Geological Survey authors.

"No current usage" (†) implies that a name has been abandoned or has fallen into disuse. Former usage and, if known, replacement name given in parentheses ( ).

Slash (/) indicates name conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).

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