Pg. 30, 40 and 1914 (USGS Bull. 586). Fork Mountain slate. Gray to greenish and chocolate-colored slates, containing thin layers of quartzite in lower part; much jointed, but withstands weathering, and usually forms a bluff where it outcrops on mountain side. Overlies Arkansas novaculite and unconformably underlies Stanley shale. [Age is Pennsylvanian.]
[Named from Fork Mountain, Polk Co., southwestern AR.]
Source: US geologic names lexicon (USGS Bull. 896, p. 753).
Pg. 66. Some shale at base of Stanley shale has in places been altered to slate, to which the name "Fork Mountain slate" has been earlier applied. [This name has been discarded. The beds are only a local facies of Stanley shale.]
Source: US geologic names lexicon (USGS Bull. 896, p. 753).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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