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Map showing publication footprint
  • Usage in publication:
    • Conococheague limestone*
  • Modifications:
    • Original reference
  • Dominant lithology:
    • Limestone
    • Sandstone
  • AAPG geologic province:
    • Appalachian basin
Publication:

Stose, G.W., 1908, The Cambro-Ordovician limestones of the Appalachian Valley in southern Pennsylvania: Journal of Geology, v. 16, p. 698-714.


Summary:

Pg. 701-703; USGS Geol. Atlas of the US, Mercersburg-Chambersburg folio, no. 170, p. 6, 1909. Conococheague limestone. Closely banded dark-blue limestone, characterized by beds containing thin sandy laminae and quartz grains that weather into hard shale fragments and thin slabby sandstones. Base marked by siliceous beds and conglomerates of two kinds. Thickness is 1,635+/- feet. Underlies Beekmantown limestone and overlies Elbrook formation. Fossils (trilobites, brachiopods). Age is Late Cambrian (Saratogan).
Named from Conococheague Creek in Scotland, Franklin Co., central southern PA.
[Type section: along banks of Conococheague Creek in town of Scotland, Scotland 7.5-min quadrangle, Franklin Co., central southern PA. Extends into western MD, and northwestern VA.]

Source: Publication; US geologic names lexicon (USGS Bull. 896, p. 508).


Map showing publication footprint
  • Usage in publication:
    • Conococheague limestone*
  • Modifications:
    • Areal extent
  • AAPG geologic province:
    • Appalachian basin
Publication:

Stose, G.W., and Swartz, C.K., 1912, Description of the Pawpaw and Hancock quadrangles [Maryland-West Virginia-Pennsylvania]: U.S. Geological Survey Geologic Atlas of the United States Folio, Pawpaw-Hancock folio, no. 179, 24 p.


Summary:

Geographically extended into MD and WV (actually, only shows up in Hancock quadrangle, WV, but must be extended through MD by default). Listed as Upper Cambrian in stratigraphic column. Thickness approximately 1250 feet.

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


Map showing publication footprint
  • Usage in publication:
    • Conococheague limestone*
  • Modifications:
    • Areal extent
  • AAPG geologic province:
    • Appalachian basin
Publication:

King, P.B., 1950, Geology of the Elkton area, Virginia: U.S. Geological Survey Professional Paper, 230, 82 p. [Available online from the USGS PubsWarehouse: http://pubs.er.usgs.gov/pubs/pp/pp230]


Summary:

Geographically extended to VA. Overlies Elbrook dolomite; underlies Beekmantown dolomite. Same lithologic features as in type area.

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


Map showing publication footprint
  • Usage in publication:
    • Conococheague limestone
  • Modifications:
    • Revised
  • AAPG geologic province:
    • Appalachian basin
Publication:

Wilson, J.L., 1952, Upper Cambrian stratigraphy in the central Appalachians: Geological Society of America Bulletin, v. 63, no. 3, p. 275-322.


Summary:

Revised lower part of formation (dolomite-orthoquartzite) as Big Spring Station Member of Conococheague Limestone.

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


Map showing publication footprint
  • Usage in publication:
    • Conococheague formation*
  • Modifications:
    • Revised
  • AAPG geologic province:
    • Appalachian basin
Publication:

Sando, W.J., 1958, Lower Ordovician section near Chambersburg, Pennsylvania: Geological Society of America Bulletin, v. 69, no. 7, p. 837-854.


Summary:

Placed upper 200 feet of Conococheague into a lower member of the Stonehenge limestone in type area. He believes by doing this that the contact between these formations is closer to the Cambrian-Ordovician boundary (used several fossil taxa to reach this conclusion).

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


Map showing publication footprint
  • Usage in publication:
    • Conococheague limestone*
  • Modifications:
    • Areal extent
  • AAPG geologic province:
    • Appalachian basin
Publication:

King, P.B., and Ferguson, H.W., 1960, Geology of northeasternmost Tennessee, with a section on the description of the basement rocks by Warren Hamilton: U.S. Geological Survey Professional Paper, 311, 136 p., Prepared in cooperation with Tennessee Div. Geol [Available online from the USGS PubsWarehouse: http://pubs.er.usgs.gov/pubs/pp/pp311]


Summary:

Geographically extended to northeastern TN as Conococheague limestone of Knox group. Lower part coarsely crystalline black fetid dolomite that forms ledges, upper part contains four or more 1 to 2 feet thick sandstone beds associated with limestone containing crinkled argillaceous laminae or ribbons. Resembles Conococheague of Virginia. Thickness probably less than 1000 feet.

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


Map showing publication footprint
  • Usage in publication:
    • Conococheague Group
  • Modifications:
    • Revised
  • AAPG geologic province:
    • Appalachian basin
Publication:

Geyer, A.R., Buckwalter, T.V., McLaughlin, D.B., and Gray, Carlyle, 1963, Geology and mineral resources of the Womelsdorf quadrangle: Pennsylvania Geological Survey Topographic and Geologic Atlas, 4th series, 177c, 96 p., scale 1:24,000


Summary:

Raised Conococheague to Group rank with 3 formations: Snitz Creek Formation, Millbach Formation, and Richland Formation (lowest to highest). Snitz Creek is predominantly dolomite, Millbach is interbedded limestone and dolomite, and Richland is predominantly dolomite. Conococheague Group is shown as Upper Cambrian. Overlies the Buffalo Springs Formation; underlies Stonehenge Formation of Beekmantown Group.

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


Map showing publication footprint
  • Usage in publication:
    • Conococheague Group
  • Modifications:
    • Revised
  • AAPG geologic province:
    • Appalachian basin
Publication:

Root, S.I., 1968, Geology and mineral resources of southeastern Franklin County, Pennsylvania: Pennsylvania Geological Survey Topographic and Geologic Atlas, 4th series, 119cd, 118 p., scale 1:24,000


Summary:

Conococheague Group.

Raised to group status for eastern valley. Divided into Zullinger Formation and Shadygrove Formation (lowest to highest). Does not recognize Big Spring Station Member of previous Conococheague Formation, equivalents are in lower part of Zullinger Formation. Conococheague Group is Middle and Upper Cambrian is stratigraphic column. Overlies Elbrook Formation; underlies Stoufferstown Formation of Beekmantown Group.

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


Map showing publication footprint
  • Usage in publication:
    • Conococheague Limestone*
  • Modifications:
    • Age modified
    • Biostratigraphic dating
  • AAPG geologic province:
    • Appalachian basin
Publication:

Orndorff, R.C., 1988, Latest Cambrian and earliest Ordovician conodonts from the Conococheague and Stonehenge Limestones of northwestern Virginia, IN Sando, W.J., ed., Shorter contributions to paleontology and stratigraphy: U.S. Geological Survey Bulletin, 1837-A, p. A1-A18.


Summary:

Cambrian-Ordovician boundary, as approximated near the base of the conodont CORDYLODUS PROAVUS Zone (base of trilobite MISSISQUOIA Zone), is 43 meters below contact with overlying Stonehenge Limestone in northwestern Virginia. This contact may be diachronous along and across strike in the Appalachians.

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


Map showing publication footprint
  • Usage in publication:
    • Conococheague Limestone*
  • Modifications:
    • Biostratigraphic dating
  • AAPG geologic province:
    • Appalachian basin
Publication:

Harris, A.G., Stamm, N.R., Weary, D.J., Repetski, J.E., Stamm, R.G., and Parker, R.A., 1994, Conodont color alteration index (CAI) map and conodont-based age determinations for the Winchester 30' x 60' quadrangle and adjacent area, Virginia, West Virginia, and Maryland: U.S. Geological Survey Miscellaneous Field Studies Map, MF-2239, 1 sheet, 40 p., scale 1:100,000 [http://ngmdb.usgs.gov/Prodesc/proddesc_294.htm]


Summary:

Conodonts recovered from near the top of the Conococheague Limestone in the Winchester 30 X 60 minute quadrangle indicate that the contact between the Conococheague and the overlying Stonehenge Formation is probably within the CORDYLODUS LINDSTROMI zone. Depending on the placement of the Cambrian-Ordovician boundary, this boundary is very close to the formational contact.

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


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