The informal Dallas group of McConnell and Costello (1980), is here formally named the New Georgia Group, which occupies the Villa Rica antiform, an upwarp on the northwestern limb of the Austell-Frolona antiform in west-central GA. The name is changed to prevent confusion with the better known geographic locality of Dallas, TX. The New Georgia Group is an interlayered sequence of metamorphosed mafic and felsic volcanic and plutonic rocks with minor metasedimentary rocks. The Group contains the Mud Creek Formation and its Cedar Lake Quartzite Member and Villa Rica Gneiss Member. Grades upward into the stratigraphically overlying but structurally underlying Andy Mountain and Bill Arp Formations of the informal Roosterville group of the Austell-Frolona antiform. Age is Proterozoic (?).
Source: GNU records (USGS DDS-6; Reston GNULEX).
In the Greater Atlanta area of northwest GA, the New Georgia Group is composed of the Kellogg Creek Mafic Complex, Univeter Formation and its Lost Mountain Amphibolite Member and Rose Creek Schist Member, Mud Creek Formation and its Cedar Lake Quartzite Member and Villa Rica Gneiss Member, Pumpkinvine Creek Formation and its Galts Ferry Gneiss Member, Canton Formation, and Acworth Gneiss. Age is Late Proterozoic and (or) early Paleozoic.
Source: GNU records (USGS DDS-6; Reston GNULEX).
Author does not subscribe to thrust sheet stratigraphy proposed by Higgins and others (1986). He adopts the nomenclature of McConnell and Abrams (1984) with some modification. New Georgia Group is the key unit in the study area and is host for majority of the known gold deposits. Occurs in the central and northeastern part of the study area where it is exposed over a seven county area. Unit extends northeastward to the vicinity of Helen, GA. Stratigraphic order of formations composing the New Georgia is modified from McConnell and Abrams (1984). Units in probable ascending order are Mud Creek Formation, Pumpkinvine Creek Formation, Canton Formation, Kellogg Creek Mafic Complex and Acworth Gneiss, which it encloses, and Univeter Formation. Lost Mountain Amphibolite Member of Univeter Formation is here changed to Lost Mountain Member.
Source: GNU records (USGS DDS-6; Reston GNULEX).
The New Georgia Group and its Mud Creek Formation, both of Abrams and McConnell (1981), Pumpkinvine Creek Formation of McConnell (1980) and its Galts Ferry Gneiss Member of McConnell and Abrams (1984), Canton Formation as used by McConnel and Abrams (1984), and Univeter Formation and its Rose Creek Schist Member and Lost Mountain Amphibolite Member, all of McConnell and Abrams (1984), are here abandoned. The Cedar Lake Quartzite Member and Villa Rica Gneiss Member of the Mud Creek are revised as the Cedar Lake Member of the Ropes Creek Metabasalt and the Villa Rica Gneiss. New Georgia Group rocks are assigned to units in the Ropes Creek and Sandy Springs thrust sheets.
Source: GNU records (USGS DDS-6; Reston GNULEX).
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