San Angelo Formation

Some studies argued that the San Angelo Formation belongs to the Kungurian stage of the Cisuralian series because it underlies the Blaine Formation, which is, according to the same studies, either upper Kungurian or lower Guadalupian.{{sfn|DiMichele|Mamay|Chaney|Hook|2001}}{{sfn|Lucas|Golubev|2019}} However, a recent study concluded that Olson was correct in regarding the San Angelo Formation as belonging to the Roadian, and that the Blaine Formation also dates from the Roadian.{{cite journal |last1=Laurin |first1=Michel |last2=Hook |first2=Robert W. |title=The age of North America’s youngest Paleozoic continental vertebrates: a review of data from the Middle Permian Pease River (Texas) and El Reno (Oklahoma) Groups |journal=BSGF - Earth Sciences Bulletin |date=2022 |volume=193 |pages=10 |doi=10.1051/bsgf/2022007 |url=https://doi.org/10.1051/bsgf/2022007 |language=en}}

Everett C. Olson regarded the San Angelo Formation as preserving some of the oldest known therapsids, several of which he classified in a taxon he called Eotheriodonta.{{sfn|Olson|1962}} These taxa are now interpreted as caseids and sphenacodontids, not therapsids.{{sfn|Sidor|Hopson|1995}}

{{Paleobiota-key-compact}}

{{Portal|Earth sciences|Texas|Paleontology}}

• List of fossiliferous stratigraphic units in Texas
• Paleontology in Texas

{{reflist}}

{{refbegin|indent=yes}}

• {{Cite journal| volume = 75| issue = 2| pages = 12| last1 = DiMichele| first1 = William A.| last2 = Mamay| first2 = Sergius H.| last3 = Chaney| first3 = Dan S.| last4 = Hook| first4 = Robert W.| last5 = Nelson| first5 = W. John| title = An Early Permian flora with Late Permian and Mesozoic affinities from North-Central Texas| journal = Journal of Paleontology| date = 2001}}
• {{Cite journal| doi = 10.1080/14772019.2010.492645| issn = 1477-2019| volume = 9| issue = 2| pages = 261–304| last = Kammerer| first = Christian F.| title = Systematics of the Anteosauria (Therapsida: Dinocephalia)| journal = Journal of Systematic Palaeontology| date = 2011}}
• {{Cite journal| pages = 5| last1 = Lucas| first1 = Spencer G| last2 = Golubev| first2 = Valeriy K| title = Age and duration of Olson’s Gap, a global hiatus in the Permian tetrapod fossil record| journal = Permophiles| date = 2019}}
• {{Cite journal| doi = 10.2307/1005904| issn = 0065-9746| volume = 52| issue = 2| pages = 1–224| last = Olson| first = Everett C.| title = Late Permian Terrestrial Vertebrates, U. S. A. and U. S. S. R.| journal = Transactions of the American Philosophical Society| date = 1962| url = https://www.jstor.org/stable/1005904| jstor = 1005904}}
• {{Cite journal| doi = 10.1086/626109| issn = 0022-1376 | volume = 61| issue = 5| pages = 389–423| last1 = Olson| first1 = Everett C.| last2 = Beerbower| first2 = James R.| title = The San Angelo Formation, Permian of Texas, and Its Vertebrates| journal = The Journal of Geology| date = 1953| jstor = 30079693}}
• {{Cite journal | last1 = Sidor| first1 = C. A.| last2 = Hopson| first2 = J. A.| title = The taxonomic status of the Upper Permian eotheriodont therapsids of the San Angelo Formation (Guadalupian), Texas| date = 1995 | journal = Journal of Vertebrate Paleontology | volume = 15 | issue = 3A | pages = 53A }}

{{refend}}

Category:Permian geology of Texas

{{Texas-geologic-formation-stub}}

{{Permian-stub}}