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National Geologic Map Database

Geologic Unit: Blockhouse

Usage:

Blockhouse Shale (GA,TN*)
Blockhouse Shale of Chickamauga Group (TN)


Subunits:

(alphabetical) --all in TN*: Toqua Sandstone Member, Whitesburg Limestone Member.


Geologic age:

Late Ordovician (Mohawkian; Turinian)*


Type section, locality, area and/or origin of name:

Type section: base of section 800 ft southwest of bench mark F132Y (972 ft elevation) extending souteastward up a gullied hillside, Blockhouse quadrangle, Blount Co., TN (Neuman, 1955).


AAPG geologic province:

Appalachian basin*


For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.

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 ( ).

Slash (/) indicates name does not conform with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). This may be explained within brackets ([ ]).