Word Formation

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Word Formation
Stratigraphic range: Roadian-Wordian
~272–265.1  Ma
Leptodus100711.jpg
Fossil from the Word Formation
Type Formation
Sub-unitsAppel Ranch, China Tank & Willis Ranch members
Overlies Road Canyon Formation
Lithology
Primary Limestone
Location
Coordinates 30°24′N103°12′W / 30.4°N 103.2°W / 30.4; -103.2
Approximate paleocoordinates 1°36′N33°00′W / 1.6°N 33.0°W / 1.6; -33.0
Region Texas
CountryFlag of the United States (23px).png  United States
Extent Glass Mountains
Type section
Named forOld Word Ranch
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Word Formation (the United States)
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Word Formation (Texas)

The Word Formation is a geologic formation in Texas. [1] It preserves fossils dating back to the Permian period. It is probably named for the Old Word Ranch in the Glass Mountains of Brewster County. [2]

Contents

Defining formation

The Wordian age of the Permian Period is named for the Word Formation. [3]

Subdivisions

The formation is subdivided into three members, from young to old:

Fossil content

The limestone formation contains marine gastropods, brachiopods and ammonites. [1]

Vertebrate paleofauna

See also

Related Research Articles

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References

  1. 1 2 Word Formation at Fossilworks.org
  2. Word Formation by USGS, retrieved 5 January 2017
  3. Old Word Ranch, Glass Mountains at Fossilworks.org
  4. Appel Ranch member at Fossilworks.org
  5. China Tank member at Fossilworks.org
  6. Willis Ranch member at Fossilworks.org

Further reading