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

Wampler, J.M., Neathery, T.L., and Bentley, R.D., 1970, Age relations in the Alabama Piedmont, IN Bentley, R.D., and Neathery, T.L., eds., Geology of the Brevard fault zone and related rocks of the Inner Piedmont of Alabama: Alabama Geological Society Annual Field Trip Guidebook, December 4-5, 1970, no. 8, p. 81-90.


Summary:

Rockford Granite of Pinckneyville Granite Complex named in Coosa Co., AL. Age of 317+/-10 m.y. determined from unmetamorphosed Rockford pluton that intruded the Wedowee.

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


Map showing publication footprint
  • Usage in publication:
    • Rockford Granite
  • Modifications:
    • Overview
    • Age modified
  • AAPG geologic province:
    • Piedmont-Blue Ridge province
Publication:

Drummond, M.S., 1987, Rockford Granite, Coosa County, Alabama; I. Geologic setting, occurrence, petrography and mineral chemistry, IN Drummond, M.S., and Green, N.L., eds., Granites of Alabama: Alabama Geological Survey Special Publication, no. 2, p. 117-130.


Summary:

Rockford described as a synmetamorphic suite of strongly peraluminous granites, trondhjemites, and granodiorites hosted by Wedowee and Hatchet Creek Groups. Occurs principally around the town of Rockford. Age given in this report as Early Devonian (Acadian). [This is first of three papers in this volume dealing solely with the Rockford Granite.]

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


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

Russell, G.S., Odom, A.L., and Russell, C.W., 1987, Uranium-lead and rubidium-strontium isotopic evidence for the age and origin of granitic rocks in the northern Alabama Piedmont, IN Drummond, M.S., and Green, N.L., eds., Granites of Alabama: Alabama Geological Survey Special Publication, no. 2, p. 239-249.


Summary:

Term used for granitic rock in and southwest of town of Rockford, Coosa Co. Zircons from Rockford, Bluff Springs, Blakes Ferry, and Almond granites have 207Pb/206Pb ages of 438 to 868 Ma. This wide range represents mixing of inherited zircons of probably Grenville age with magmatic zircons. The assumed age of the Rockford is 460 m.y. maximum to 300 m.y. minimum.

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


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

Raymond, D.E., Osborne, W.E., Copeland, C.W., and Neathery, T.L., 1988, Alabama stratigraphy: Geological Survey of Alabama Circular, no. 140, 97 p.


Summary:

Rockford Granite described as strongly peraluminous granite, trondhjemite, and granodiorite, fine- to medium-grained, leucocratic, locally pegmatitic. Generalized age is Precambrian to Paleozoic.

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


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Asterisk (*) indicates usage by the U.S. Geological Survey. Other usages by state geological surveys.

"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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