The Red Beds of Texas and Oklahoma are a group of

Early Permian 01 or 01 may refer to: * The year 2001, or any year ending with 01 * The month of January * 1 (number) Music * '01 (Richard Müller album), ''01'' (Richard Müller album), 2001 * 01 (Urban Zakapa album), ''01'' (Urban Zakapa album), 2011 * ''01011 ...

-age geologic strata in the southwestern United States cropping out in north-central

Texas Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...

and south-central

Oklahoma Oklahoma ( ; Choctaw language, Choctaw: , ) is a landlocked U.S. state, state in the South Central United States, South Central region of the United States. It borders Texas to the south and west, Kansas to the north, Missouri to the northea ...

. They comprise several stratigraphic groups, including the Clear Fork Group, the

Wichita Group The Wichita Group is a geologic group in the Permian Red Beds. It preserves fossils dating back to the Permian period. See also * List of fossiliferous stratigraphic units in Texas * Paleontology in Texas Paleontology in Texas refers to pa ...

, and the Pease River Group.Nelson, John W., Robert W. Hook, and Dan S. Chaney (2013)
Lithostratigraphy of the Lower Permian (Leonardian) Clear Fork Formation of North-Central Texas
from The Carboniferous-Permian Transition: Bulletin 60, ed. Spencer G. Lucas et al. New Mexico Museum of Natural History and Science, pg. 286-311. Retrieved December 28, 2017. The Red Beds were first explored by American paleontologist

Edward Drinker Cope Edward Drinker Cope (July 28, 1840 – April 12, 1897) was an American zoologist, paleontology, paleontologist, comparative anatomy, comparative anatomist, herpetology, herpetologist, and ichthyology, ichthyologist. Born to a wealthy Quaker fam ...

starting in 1877.Cope, E.D. (1878)
Descriptions of Batrachia and Reptilia from the Permian Formation of Texas.
Proceedings of the American Philosophical Society, vol. 17, no. 101, pg. 505-30. Retrieved December 28, 2017. Fossil remains of many Permian

tetrapods A tetrapod (; from Ancient Greek τετρα- ''(tetra-)'' 'four' and πούς ''(poús)'' 'foot') is any four- limbed vertebrate animal of the clade Tetrapoda (). Tetrapods include all extant and extinct amphibians and amniotes, with the lat ...

(four-limbed vertebrates) have been found in the Red Beds, including those of ''

Dimetrodon ''Dimetrodon'' ( or ; ) is an extinct genus of sphenacodontid synapsid that lived during the Cisuralian (Early Permian) Epoch (geology), epoch of the Permian period, around 295–272 million years ago. With most species measuring long and ...

'', ''

Edaphosaurus ''Edaphosaurus'' (, meaning "pavement lizard" for dense clusters of its teeth) is a genus of extinct edaphosaurid synapsids that lived in what is now North America and Europe around 303.4 to 272.5 million years ago, during the Late Carboniferous ...

'', ''

Seymouria ''Seymouria'' is an extinct genus of seymouriamorph from the Early Permian of North America and Europe. Although they were amphibians (in a biological sense), ''Seymouria'' were well-adapted to life on land, with many reptilian features—so ma ...

'', ''

Platyhystrix ''Platyhystrix'' (from Greek: πλατύς ''platús'', 'flat' and Greek: ῠ̔́στρῐξ ''hústrix'', 'porcupine') is an extinct temnospondyl amphibian with a distinctive sail along its back, similar to the unrelated synapsids, '' Dimetro ...

'', and '' Eryops''. A recurring feature in many of these animals is the sail structure on their backs. EdaphosaurusDB

Location

Deposits dating from the

Permian The Permian ( ) is a geologic period and System (stratigraphy), stratigraphic system which spans 47 million years, from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.902 Mya. It is the s ...

are present contiguously stretching from central Texas all the way into southern

Nebraska Nebraska ( ) is a landlocked U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders South Dakota to the north; Iowa to the east and Missouri to the southeast, both across the Missouri River; Ka ...

.King, Philip B., and Helen M. Beikman (1976)
The Paleozoic and Mesozoic Rocks; A Discussion to Accompany the Geologic Map of the United States.
United States Geological Survey, Professional Paper 903, pg. 29-32. Retrieved December 29, 2017. In Nebraska and

Kansas Kansas ( ) is a landlocked U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to the west. Kansas is named a ...

, deposits of light-colored limestone are frequent, while red-colored rocks are rare. In Oklahoma, the light-colored

limestone Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science) ...

transitions gradually into red-colored

sandstone Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sand ...

and

shale Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of Clay mineral, clay minerals (hydrous aluminium phyllosilicates, e.g., Kaolinite, kaolin, aluminium, Al2Silicon, Si2Oxygen, O5(hydroxide, OH)4) and tiny f ...

until the limestone is virtually nonexistent in north-central

.Case, E.C. (1915)
Chapter 1: Description of the Southern Portion of the Plains Province
in The Permo-Carboniferous Red Beds of North America and Their Vertebrate Fauna. Carnegie Institute of Washington, pg. 5-61. Retrieved December 29, 2017. The portion of the red beds with abundant fossil deposits is in Texas between the Red River and the

Salt Fork Brazos River The Salt Fork Brazos River is a braided, highly intermittent stream about long, heading along the edge of the Llano Estacado about east-southeast of Lubbock, Texas. From its source, it flows generally east-southeastward to join the Double Moun ...

.Benton, Michael (2001)
Chapter Three: Four Feet on the Ground
from The Book Of Life: An Illustrated History of the Evolution of Life on Earth, ed. Stephen Jay Gould. W.W. Norton: pg. 93-5. Retrieved December 28, 2017. The area includes the city of

Wichita Falls Wichita Falls ( ) is a city in and the county seat of Wichita County, Texas, United States. It is the principal city of the Wichita Falls metropolitan statistical area, which encompasses all of Archer, Clay, and Wichita Counties. According to ...

, and rural communities such as Seymour and Archer City.Barnes, V.E., et al. (1987)
Geologic atlas of Texas, Wichita Falls-Lawton sheet.
University of Texas at Austin Bureau of Economic Geology. Retrieved December 28, 2017.

Properties

The Texas and Oklahoma red beds are

sedimentary rock Sedimentary rocks are types of rock (geology), rock formed by the cementation (geology), cementation of sediments—i.e. particles made of minerals (geological detritus) or organic matter (biological detritus)—that have been accumulated or de ...

s, mostly consisting of sandstone and red

mudstone Mudstone, a type of mudrock, is a fine-grained sedimentary rock whose original constituents were clays or muds. Mudstone is distinguished from ''shale'' by its lack of fissility.Blatt, H., and R.J. Tracy, 1996, ''Petrology.'' New York, New York, ...

.Sander, P. Martin (1989)
Early Permian depositional environments and pond bonebeds in central Archer County, Texas.
Palaeogeography, Palaeoclimatology, Palaeoecology, vol. 69, pg. 1-21. Retrieved December 28, 2017. The red color of the rocks is due to the presence of

ferric oxide Iron(III) oxide or ferric oxide is the inorganic compound with the formula . It occurs in nature as the mineral hematite, which serves as the primary source of iron for the steel industry. It is also known as red iron oxide, especially when us ...

.Van Houten, Franklin (1973)
Origin of Red Beds: A review - 1961-1972.
Annual Review of Earth and Planetary Sciences, Vol. 1, pg. 39-61. Retrieved December 28, 2017. The rocks were deposited during the early Permian in a warm, moist climate,Baker, Charles Laurence (1916)
Origin of Texas Red Beds.
Bulletin of the

University of Texas The University of Texas at Austin (UT Austin, UT, or Texas) is a public research university in Austin, Texas, United States. Founded in 1883, it is the flagship institution of the University of Texas System. With 53,082 students as of fall 2 ...

, No. 26. Retrieved December 28, 2017. with seasonal periods of dry conditions.Chaney, D.S., and W.A. DiMichele (2007).
Paleobotany of the classic redbeds of north central Texas.
Proceedings of the XVth International Congress on Carboniferous and Permian Stratigraphy, pg. 357-66. The Netherlands: Utrecht. Retrieved December 29, 2017.

Stratigraphy

The Texas and Oklahoma red beds can be split into three primary

stratigraphic Stratigraphy is a branch of geology concerned with the study of rock layers (strata) and layering (stratification). It is primarily used in the study of sedimentary and layered volcanic rocks. Stratigraphy has three related subfields: lithost ...

groups: the

, the Clear Fork Group, and the Pease River Group. The Wichita Group is the oldest of the three groups, having been deposited in the

Sakmarian In the geologic timescale, the Sakmarian is an age or stage of the Permian period. It is a subdivision of the Cisuralian Epoch or Series. The Sakmarian lasted between 293.52 and million years ago (Ma). It was preceded by the Asselian and fo ...

age.Johnson, Garyd (2013)
Xenacanth Sharks and other Vertebrates from the Geraldine Bonebed, Lower Permian of Texas
from The Carboniferous-Permian Transition: Bulletin 60, ed. Spencer G. Lucas et al. New Mexico Museum of Natural History and Science, pg. 161-7. Retrieved December 28, 2017. The Wichita Group contains some of the richest fossil deposits in the red beds, including the Geraldine Bonebed in Archer County. The Pease River Group is the most recent deposition, occurring during the

Guadalupian The Guadalupian is the second and middle Series (stratigraphy), series/Epoch (geology), epoch of the Permian. The Guadalupian was preceded by the Cisuralian and followed by the Lopingian. It is named after the Guadalupe Mountains of New Mexico an ...

epoch. The Clear Fork Group is in between the other two, being deposited during the

Kungurian In the geologic timescale, the Kungurian is an age or stage of the Permian. It is the latest or upper of four subdivisions of the Cisuralian Epoch or Series. The Kungurian lasted between and million years ago (Ma). It was preceded by the Arti ...

age. The stratigraphic groups are layered such that the Pease River Group overlies the Clear Fork Group, which overlies the Wichita group. From youngest to oldest: * Pease River Group ** Blaine Formation ** San Angelo Formation * Clear Fork Group ** Upper Clear Fork ( Choza Formation) ** Middle Clear Fork (

Vale Formation The Vale Formation is a geological formation in north-central Texas, a component of the Texas red beds preserving sediments and fossils from the Early Permian Leonardian series. It occupies the middle part of the Clear Fork Group, above the A ...

) ** Lower Clear Fork ( Arroyo Formation) *

Waggoner Ranch Formation The Waggoner Ranch Formation is a geologic formation in northern Texas. It preserves fossils dating back to the Artinskian to Kungurian stages of the Permian The Permian ( ) is a geologic period and System (stratigraphy), stratigraphic syste ...

(equivalent to the Lueders Formation, Clyde Formation, Belle Plains Formation) ** Petrolia Formation (equivalent to the Belle Plains Formation) ** Nocona Formation (equivalent to the

Admiral Formation The Admiral Formation is a geologic formation in Texas. It preserves fossils dating back to the Permian period. See also * List of fossiliferous stratigraphic units in Texas * Paleontology in Texas Paleontology in Texas refers to paleontolog ...

) * Bowie Group **

Archer City Formation The Archer City Formation is a Formation (geology), geological formation in north-central Texas, preserving fossils from the Asselian and early Sakmarian Stage (stratigraphy), stages of the Permian Period (geologic time), period. It is the earlie ...

(equivalent to the Moran Formation, Putnam Formation)

Fossil record

In 1877, Edward Drinker Cope was the first

paleontologist Paleontology, also spelled as palaeontology or palæontology, is the scientific study of the life of the past, mainly but not exclusively through the study of fossils. Paleontologists use fossils as a means to classify organisms, measure geolo ...

to study the red beds in search of

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserve ...

s. Cope employed collectors to aid him in his search for bones, including Swiss botanist

Jacob Boll Jacob Boll (28 May 1828 – 29 September 1880) was a Swiss naturalist and entomologist especially noted for his exploration of the Texas Red Beds. Boll was born 1828 in Würenlos, Switzerland, and educated as a pharmacist in Switzerland and Germ ...

. After Boll's death in 1880 while collecting, Cope employed preacher W.F. Cummins to continue the search. After Cope, paleontologists such as

Ermine Cowles Case Ermine Cowles Case (September 11, 1871CASE, Emine Cowles
in ''

The Red Beds between Wichita Falls, Texas, and Las Vegas, New Mexico, in Relation to their Vertebrate Fauna.
The Journal of Geology, vol. 22, no. 3, pg. 243-59. Retrieved December 28, 2017. and

Alfred Romer Alfred Sherwood Romer (December 28, 1894 – November 5, 1973) was an American paleontologist and biologist and a specialist in vertebrate evolution. Biography Alfred Romer was born in White Plains, New York, the son of Harry Houston Romer an ...

Romer, Alfred, and Llewellyn Price (1940)
Review of the Pelycosauria.
Geological Society of America, Vol. 28, Special Paper. Retrieved December 28, 2017. found rich deposits of Permian-era

tetrapod A tetrapod (; from Ancient Greek :wiktionary:τετρα-#Ancient Greek, τετρα- ''(tetra-)'' 'four' and :wiktionary:πούς#Ancient Greek, πούς ''(poús)'' 'foot') is any four-Limb (anatomy), limbed vertebrate animal of the clade Tetr ...

Geraldine Bonebed

The most prolific fossil site in the red beds is the Geraldine Bonebed within the Nocona Formation of the Wichita Group. During the Permian, the bonebed was the site of a freshwater pond. After a catastrophic event this became the burial site for a variety of terrestrial and marine animals.Sander, P. Martin (1987)
Taphonomy of the Lower Permian Geraldine Bonebed in Archer County, Texas.
Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 61, pg. 221-36. Retrieved December 28, 2017. As a result, the bonebed contains a cross-section of life during the early Permian. Plant remains found in the bonebed include ''

Calamites ''Calamites'' is a genus of Extinction, extinct arborescent (tree-like) horsetails to which the modern horsetails (genus ''Equisetum'') are closely related. Unlike their Herbaceous plant, herbaceous modern cousins, these plants were medium-size ...

'',

fern The ferns (Polypodiopsida or Polypodiophyta) are a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. They differ from mosses by being vascular, i.e., having specialized tissue ...

s, and

conifers Conifers () are a group of cone-bearing seed plants, a subset of gymnosperms. Scientifically, they make up the division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single extant class, Pinopsida. All e ...

. Marine life present in the bonebed include ''

Xenacanthus ''Xenacanthus'' (from Ancient Greek wikt:ξένος, ξένος, xénos, 'foreign, alien' + wikt:ἄκανθος, ἄκανθος, akanthos, 'spine') is an extinct genus of Xenacanthida, xenacanth cartilaginous fish. It lived in freshwater environ ...

'',

ostracod Ostracods, or ostracodes, are a Class (biology), class of the crustacean, Crustacea (class Ostracoda), sometimes known as seed shrimp. Some 33,000 species (only 13,000 of which are extant taxon, extant) have been identified,Brandão, S.N.; Antoni ...

s, and

lungfish Lungfish are freshwater vertebrates belonging to the class Dipnoi. Lungfish are best known for retaining ancestral characteristics within the Osteichthyes, including the ability to breathe air, and ancestral structures within Sarcopterygii, inc ...

. The Geraldine Bonebed is most famous as a prolific source of

temnospondyls Temnospondyli (from Greek τέμνειν, ''temnein'' 'to cut' and σπόνδυλος, ''spondylos'' 'vertebra') or temnospondyls is a diverse ancient order of small to giant tetrapods—often considered primitive amphibians—that flourished wo ...

synapsids Synapsida is a diverse group of tetrapod vertebrates that includes all mammals and their extinct relatives. It is one of the two major clades of the group Amniota, the other being the more diverse group Sauropsida (which includes all extant rept ...

, basal

reptiliomorphs Reptiliomorpha (meaning reptile-shaped; in PhyloCode known as ''Pan-Amniota'') is a clade containing the amniotes and those tetrapods that share a more recent common ancestor with amniotes than with living amphibians (lissamphibians). It was defi ...

and

reptiles Reptiles, as commonly defined, are a group of tetrapods with an ectothermic metabolism and Amniotic egg, amniotic development. Living traditional reptiles comprise four Order (biology), orders: Testudines, Crocodilia, Squamata, and Rhynchocepha ...

, including partial and complete skeletons of '' Archeria'', '' Eryops'', ''

'', ''

Bolosaurus ''Bolosaurus'' (from Ancient Greek ''bolos'', "lump" + ''sauros'': lizard]) is an extinct genus of bolosaurid reptile from the Cisuralian Epoch (geology), epoch (middle Sakmarian to early Kungurian stages) of North Asia and North America (Red Be ...

'', ''

Trimerorhachis ''Trimerorhachis'' is an extinct genus of dvinosaurian temnospondyl within the family (biology), family Trimerorhachidae. It is known from the Early Permian of the southwestern United States, with most fossil specimens having been found in the Re ...

'', '' Zatrachys'', and ''

Ophiacodon ''Ophiacodon'' (meaning "snake tooth") is an extinct genus of synapsid belonging to the family Ophiacodontidae that lived from the Late Carboniferous to the Early Permian in North America and Europe. The genus was named along with its type specie ...

''.

Clear Fork deposits

The Clear Fork Group also contains multiple fossil sites. Like the Geraldine Bonebed and other Wichita Group sites, the Clear Fork Group is most famous for its early Permian amphibian deposits, especially '' Seymouria baylorensis''. The species and genus were first discovered in 1904 by German paleontologist Ferdinand Broili.Williston, S.W. (1911)
Restoration of ''Seymouria baylorensis'' Broili, an American Cotylosaur.
The Journal of Geology, vol. 19, no. 3, pg. 232–7. Retrieved December 29, 2017. ''Seymouria baylorensis'' is named for the location of its discovery in Baylor County near the city of Seymour. As one of the few ''Seymouria'' bone sites in the world, paleontologists have studied the Clear Fork deposit for evidence of ''Seymouria'' as a

transitional fossil A transitional fossil is any fossilized remains of a life form that exhibits traits common to both an ancestral group and its derived descendant group. This is especially important where the descendant group is sharply differentiated by gross ...

between aquatic and terrestrial animals, as well as ''Seymourias close relationship to

amniote Amniotes are tetrapod vertebrate animals belonging to the clade Amniota, a large group that comprises the vast majority of living terrestrial animal, terrestrial and semiaquatic vertebrates. Amniotes evolution, evolved from amphibious Stem tet ...

s.Laurin, Michel (1996)
A redescription of the cranial anatomy of ''Seymouria baylorensis'', the best known seymouriamorph.
PaleoBios, Vol. 17, no. 1, pg. 1-16. Retrieved December 29, 2017.Carrol, Robert L., and Robert B. Holmes (2008)
Evolution of the Appendicular Skeleton of Amphibians
from Fins into Limbs: Evolution, Development, and Transformation, ed. Brian K. Hall. University of Chicago Press, pg. 206-9. The Clear Fork Group also contains deposits of plant species throughout its different sections. The increasing prevalence of seed plants with pockets of water-based plants can be used to infer a wet, but drying climate.

References

{{reflist Geology of Texas Geology of Oklahoma Permian paleontological sites