Poe Bridge Mountain Formation of Wedowee Group is here named in Clay and Cleburne Cos, east-central AL. Described as interlayered sequence of coarse- to fine-grained feldspathic graphite schist, graphite-quartz schist, graphitic quartzite, garnet-biotite-muscovite schist and gneiss, and amphibolite. Weathers to distinctive purple-brown saprolite. Generalized age is Paleozoic.
Source: GNU records (USGS DDS-6; Reston GNULEX).
Author here proposes that Ashland Mica Schist as used by Adams (1926) be elevated to supergroup status to incorporate the groups of the Coosa block in east-central Alabama. Ashland includes Poe Bridge Mountain and Mad Indian Groups in the northeastern part of the study area (Clay, Randolph, and Cleburne Cos) and the correlative Higgins Ferry and Hatchet Creek Groups in the southwestern part (Coosa and Chilton Cos). The contact between the Mad Indian and Poe Bridge Mountain Groups and between the Higgins Ferry and Hatchet Creek Groups appears to be stratigraphic rather than tectonic, but relative age of units is undetermined.
Source: GNU records (USGS DDS-6; Reston GNULEX).
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