The Bigfork Chert is a Middle to Late
Ordovician geologic formation in the
Ouachita Mountains of
Arkansas and
Oklahoma
Oklahoma (; Choctaw language, Choctaw: ; chr, ᎣᎧᎳᎰᎹ, ''Okalahoma'' ) is a U.S. state, state in the South Central United States, South Central region of the United States, bordered by Texas on the south and west, Kansas on the nor ...
. First described in 1892, this unit was not named until 1909 by Albert Homer Purdue in his study of the Ouachita Mountains of Arkansas.
[ Purdue assigned the town of Big Fork in ]Montgomery County Montgomery County may refer to:
Australia
* The former name of Montgomery Land District, Tasmania
United Kingdom
* The historic county of Montgomeryshire, Wales, also called County of Montgomery
United States
* Montgomery County, Alabama
* Mon ...
, Arkansas as the type locality
Type locality may refer to:
* Type locality (biology)
* Type locality (geology)
See also
* Local (disambiguation)
* Locality (disambiguation)
{{disambiguation ...
, but did not designate a stratotype. As of 2017, a reference section for this unit has yet to be designated. The Bigfork Chert is known to produce planerite, turquoise, variscite, and wavellite
Wavellite is an aluminium basic phosphate mineral with formula Al3( P O4)2(O H, F)3·5 H2O. Distinct crystals are rare, and it normally occurs as translucent green radial or spherical clusters.
Discovery and occurrence
Wavellite was firs ...
minerals.
Paleofauna
Graptolites
* '' Climacograptus''[
* '' Dicellograptus''
: ''D. divaricatus''][
* '']Diplograptus
''Diplograptus'' was a Cambrian
The Cambrian Period ( ; sometimes symbolized C with bar, Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preced ...
''
: ''D. trifidus''[
: ''D. vulgatus''][
* '' Glyptograptus''][
* '' Lasiograptus''
: ''L. flaccidus''][
* '' Mesograptus''
: ''M. perexcavatus''][
* '' Orthograptus''
: ''O. quadrimucronatus''][
]
See also
* List of fossiliferous stratigraphic units in Arkansas
* Paleontology in Arkansas
Paleontology in Arkansas refers to paleontological research occurring within or conducted by people from the United States, U.S. state of Arkansas. The fossil Fossil record, record of Arkansas spans from the Ordovician to the Eocene. Nearly all of ...
References
Ordovician geology of Oklahoma
Ordovician Arkansas
Ordovician southern paleotropical deposits
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