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Geologic Units: Siloam
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Map showing publication footprint
  • Usage in publication:
    • Siloam Granite
  • Modifications:
    • Named
  • Dominant lithology:
    • Granite
  • AAPG geologic province:
    • Piedmont-Blue Ridge province
Publication:

Jones, L.M., and Walker, R.L., 1973, Rb-Sr whole-rock age of the Siloam Granite, Georgia; a Permian intrusive in the southern Appalachians: Geological Society of America Bulletin, v. 84, no. 11, p. 3653-3658.


Summary:

Siloam Granite (new) is described as pink and white coarse porphyry containing pink microcline phenocrysts. Covers 100 sq mi. Youngest intrusive of the area. Rb-Sr whole-rock age is 269+/-3 m.y.

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


Map showing publication footprint
  • Usage in publication:
    • Siloam Granite
  • Modifications:
    • Geochronologic dating
    • Overview
  • AAPG geologic province:
    • Piedmont-Blue Ridge province
Publication:

Whitney, J.A., and Wenner, D.B., 1980, Petrology and structural setting of post-metamorphic granites of Georgia, IN Frey, R.W., and Neathery, T.L., Excursions in southeastern geology; [Field trip nos. 14-23]; Volume 2: Geological Society of America Field Trip Guidebook, [93rd] annual meeting, Atlanta, GA, p. 351-378.


Summary:

Siloam granite described as a heterogeneous body composed of porphyritic coarse, medium, fine-grained phases, and a garnet phase. K-Ar age on biotite of 261 m.y. confirms Permian age.

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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