Named the Toqua sandstone member of the Blockhouse shale for Toqua Church, Monroe Co., eastern TN. Consists of light-gray, fine- to coarse-grained calcareous sandstone; finer-grained, well-laminated, cross-bedded sandstone in beds 4 to 12 inches thick are separated by thinner beds of dark-gray shale. Coarser grained, poorly laminated rock in beds 10 to 20 inches thick is set apart by poorly defined bedding plane partings. Unit weathers greenish brown or olive; its saprolite is yellow brown to ocherous. Thickness at type section is about 400 feet. Overlies Whitesburg limestone member and underlies dark shale member, both of the Blockhouse. The Toqua is of Middle Ordovician age.
Source: GNU records (USGS DDS-6; Reston GNULEX).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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