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Map showing publication footprint
  • Usage in publication:
    • Muhlenberg Member
  • Modifications:
    • First used
  • AAPG geologic province:
    • Appalachian basin
Publication:

Wood, C.R., and MacLachlan, D.B., 1978, Geology and groundwater resources of northern Berks County, Pennsylvania: Pennsylvania Geological Survey Water Resource Report, 4th series, no. 44, 91 p., (incl. geologic map, scale 1:62,500)


Summary:

First used the Muhlenberg Member of the Allentown Formation. Unit is middle member of formation. Consists of gray dolomite to silty dolomite; usually thick bedded with interbedded limestone, calcareous sandstone, and some shale; algal laminate structures common; some oolite and sharpstone conglomerate. Overlies the Tuckerton Member of the Allentown and underlies the Maiden Creek Member of the Allentown.

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


Map showing publication footprint
  • Usage in publication:
    • Muhlenberg Member
  • Modifications:
    • Named
  • Dominant lithology:
    • Limestone
    • Dolomite
  • AAPG geologic province:
    • Appalachian basin
Publication:

MacLachlan, D.B., 1979, Geology and mineral resources of the Temple and Fleetwood quadrangles, Berks County, Pennsylvania: Pennsylvania Geological Survey Topographic and Geologic Atlas, 4th series, 187ab, 71 p., scale 1:24,000 and 1:48,000


Summary:

Named as middle member of 3 of the Allentown Formation. Type locality is Muhlenberg Township in the southern part of the Temple quadrangle, Berks Co., PA. "Medium to medium light gray, thick-bedded magnesium limestone and dolomite, dark gray in places. Contains scattered calcareous sandstone beds up to 1 1/2 m (5 ft)." 240 m (800 ft) thick. Conformably overlies the Tuckerton Member (Allentown Formation); conformably underlies the Maiden Creek Member (Allentown Formation). Assigned to the Late Cambrian.

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


Map showing publication footprint
  • Usage in publication:
    • Muhlenberg Member*
  • Modifications:
    • Overview
  • AAPG geologic province:
    • Appalachian basin
Publication:

Drake, A.A., Jr., 1987, Geologic map of the Topton quadrangle, Lehigh and Berks Counties, Pennsylvania: U.S. Geological Survey Geologic Quadrangle Map, GQ-1609, 1 sheet, scale 1:24,000 [http://ngmdb.usgs.gov/Prodesc/proddesc_1134.htm]


Summary:

Adopted as Muhlenberg Member of the Allentown Dolomite in southeast Lehigh and Berks Counties, PA. "Medium- to light-medium-gray, thick-bedded dolomite and magnesium limestone. Unit contains interbedded calcareous sandstone...." Assigned to the Late Cambrian.

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


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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 ( ).

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