{{short description|Geological formation in the western US}} {{Use dmy dates|date=April 2023}} {{Use American English|date=April 2021}} {{Infobox rockunit | name = Chinle Formation | image = Chinle Badlands.jpg | caption = Chinle Badlands, [[Grand Staircase–Escalante National Monument]], Utah, US. | type = [[Geological formation]] | age = {{Geological range|Norian|Rhaetian}} {{period fossil range|Triassic|Norian|Rhaetian}} | period = Late Triassic | prilithology = [[fluvial]] [[mudstone]], [[siltstone]], and [[sandstone]] | otherlithology = [[paleosols]] | namedfor = [[Chinle, AZ]] | namedby = [[Herbert E. Gregory]] | region = [[Colorado Plateau]] | extent = Utah <br />Colorado<br />New Mexico<br />Arizona<br />Nevada | coordinates = {{coord|36.155|N|109.579|W|display=inline}} | unitof = | subunits = see text | underlies = [[Wingate Sandstone]], <br />[[Moenave Formation]], <br />[[Nugget Sandstone]] | overlies = [[Moenkopi Formation]] or [[Cutler Group]] | thickness = | area = | map ={{Location map+ | United States#Arizona | relief = 1 | width = 250 | float = center | places = {{Location map~ | United States#Arizona | lat_deg = 36.155 | lon_deg = -109.579 | mark = Purple pog.svg | marksize = 12 }} }} | map_caption = Type locality in Arizona |paleocoordinates={{coord|10.7|N|48.3|W|display=inline}}}}
The '''Chinle Formation''' is an [[Late Triassic|Upper Triassic]] continental [[geological formation]] of [[fluvial]], [[Lake|lacustrine]], and [[palustrine]] to [[Aeolian processes|eolian]] deposits spread across the U.S. states of [[Nevada]], [[Utah]], northern [[Arizona]], western [[New Mexico]], and western [[Colorado]]. In New Mexico, it is often raised to the status of a geological group, the '''Chinle Group'''. Some authors have controversially considered the Chinle to be synonymous to the [[Dockum Group]] of eastern Colorado and New Mexico, western [[Texas]], the [[Oklahoma]] panhandle, and southwestern [[Kansas]]. The Chinle Formation is part of the [[Colorado Plateau]], [[Basin and Range Province|Basin and Range]], and the southern section of the [[Interior Plains]].<ref name="geolexdatabase">[https://ngmdb.usgs.gov/Geolex/NewUnits/unit_4997.html GEOLEX database entry for Chinle], USGS (viewed 19 March 2006)</ref> A probable separate depositional basin within the Chinle is found in northwestern Colorado and northeastern Utah. The southern portion of the Chinle reaches a maximum thickness of a little over {{convert|520|m||sp=us}}. Typically, the Chinle rests [[unconformity|unconformably]] on the [[Moenkopi Formation]].
The Chinle Formation was probably mostly deposited in the Norian stage, according to a plethora of chronological techniques. It is a thick and fossiliferous formation with numerous named members (subunits) throughout its area of deposition.
==History of investigation== While colorful Triassic sediments of the [[Colorado Plateau]] have been investigated since the 19th century, the Chinle Formation was only formally named and described by [[Herbert E. Gregory]] in 1917. It was named for [[Chinle Valley]] in [[Apache County, Arizona]], land which is largely within the [[Navajo Nation]]. Gregory did not designate a [[Type locality (geology)|type locality]]. He split the Chinle into four subunits, labelled A (youngest) to D (oldest). This did not include the underlying Shinarump Conglomerate (named by [[Grove Karl Gilbert|G. K. Gilbert]] and [[Edwin Eugene Howell|Edwin E. Howell]] in 1875), which he considered a separate formation.<ref name="Gregory1917">{{cite book |last=Gregory |first=Herbert E. |url=https://pubs.usgs.gov/pp/0093/report.pdf |title=Geology of the Navajo country - A reconnaissance of parts of Arizona, New Mexico, and Utah |publisher=United States Geological Survey Professional Papers #93 |year=1917 |at=161 p.}}</ref>
[[United States Geological Survey]] geologists and paleontologists continued to map out the Chinle Formation through the 20th century, revising the unnamed subunits of Gregory. A basic stratigraphy of the formation was developed for north-central New Mexico by Wood and Northrop (1946),<ref name="WoodNorthrop1946">{{cite journal |last1=Wood |first1=G.H. |last2=Northrop |first2=S.A. |date=1946 |title=Geology of the Nacimiento Mountains, San Pedro Mountain, and adjacent plateaus in parts of Sandoval and Rio Arriba Counties, New Mexico |url=https://ngmdb.usgs.gov/Prodesc/proddesc_5417.htm |journal=USGS Oil and Gas Investigations |volume=OM-57 |doi=10.3133/om57 |url-access=subscription }}</ref> and stratigraphy in the Four Corners Region was established by the late 1950s. In 1956, Economic geologist [[Raymond C. Robeck]] identified and named the Temple Mountain member as the basal-most unit in the area of the [[San Rafael Swell]] of Utah. In 1957, John H. Stewart revised the Shinarump Conglomerate and renamed it the Shinarump member of the Chinle formation.
Study of the formation expanded northwards into northern Utah and Colorado, facilitated through papers by Forrest G. Poole and Stewart (1964)<ref>{{Cite journal |last1=Poole |first1=F. G. |last2=Stewart |first2=J. H. |date=1964 |title=Chinle Formation and Glen Canyon Sandstone in Northeast Utah and Northwest Colorado |url=https://books.google.com/books?id=lEmOS8y2B2IC |journal= U.S. Geol. Survey Prof. Paper|series=Geological Survey Research 1964. |language=en-US |volume=501-D |pages=93–104}}</ref> and Steve W. Sikich (1965),<ref name="sikitch-1965">{{cite journal |last1=Sikitch |first1=Steve W. |title=Upper Triassic stratigraphy in the eastern Uinta Mountains |journal=The Mountain Geologist |date=1965 |volume=2 |issue=3 |pages=167–172 |url=http://archives.datapages.com/data/rmag/mg/1965/sikich.htm }}</ref> who named informal local members equivalent to those of Arizona and New Mexico. The complete areal extent of the unit was mapped by R.F. Wilson and Stewart in 1967.<ref name="wilson-steward-1967">{{cite journal |last1=Wilson |first1=Richard F. |last2=Stewart |first2=John H. |title=Correlation of Upper Triassic and Triassic Formations between southwestern Utah and southern Nevada |journal=U.S. Geological Survey Bulletin |date=1967 |volume=1244-D |pages=D1–D20 |doi=10.3133/b1244D|doi-access=free }}</ref> Stewart and his colleagues created an expansive overview and revision of the formation in 1972, summarizing previous knowledge on Chinle stratigraphy.<ref name="StewartEtal1972">{{cite journal |last1=Stewart |first1=J.H. |last2=Poole |first2=F.G. |last3=Wilson |first3=R.F. |year=1972 |title=Stratigraphy and origin of the Chinle Formation and related Upper Triassic strata in the Colorado Plateau region, with sections on sedimentary petrology by R.A. Cadigan and conglomerate studies by William Thordarson and H.F. Albee |url=https://pubs.usgs.gov/pp/0690/report.pdf |journal=U.S. Geological Survey Professional Paper |volume=690 |doi=10.3133/pp690}}</ref>
V.C. Kelley assigned more members and revised the unit in 1972.<ref name="kelley-1972">{{cite journal |last1=Kelley |first1=V.C. |title=Geology of the Fort Sumner sheet, New Mexico |journal=New Mexico Bureau of Mines and Mineral Resources Bulletin |date=1972 |volume=98 |url=https://geoinfo.nmt.edu/publications/monographs/bulletins/downloads/98/Bulletin98.pdf }}</ref> [[Spencer G. Lucas]] and S.N. Hayden did the same thing in 1989.<ref name="lucas-hayden-1989">{{cite journal |last1=Lucas |first1=S.G. |author1-link=Spencer G. Lucas |last2=Hayden |first2=S.N. |year=1989 |title=Triassic stratigraphy of west-central New Mexico |journal=New Mexico Geological Society Field Conference Guidebook |volume=40 |pages=191–211 |url=https://nmgs.nmt.edu/publications/guidebooks/downloads/40/40_p0191_p0211.pdf }}</ref> The Rock Point Member was assigned by R.F. Dubiel in 1989.<ref name="dubiel89">{{cite book |last1=Dubiel |first1=R.F. |year=1989 |chapter=Depositional and climatic setting of the Upper Triassic Chinle Formation, Colorado Plateau |editor-last1=Lucas |editor-first1=S.G. |editor-link1=Spencer G. Lucas |editor-last2=Hunt |editor-first2=A.P. |title=Dawn of the Age of Dinosaurs in the American Southwest |publisher=New Mexico Museum of Natural History |pages=171–187 |chapter-url=https://books.google.com/books?id=Ar1hCgAAQBAJ&pg=PP1}}</ref>
The Chinle was raised to group rank by Lucas in 1993,<ref name=Lucas1993>{{cite journal |last1=Lucas |first1=S.G. |author-link1=Spencer G. Lucas |year=1993 |title=The Chinle Group: revised stratigraphy and biochronology of Upper Triassic Nonmarine strata in the western United States |journal=Museum of Northern Arizona Bulletin |volume=59 |pages=27–50}}</ref> thus also raising many of the members to formation status. He also included the formations of the [[Dockum Group]] of eastern [[New Mexico]] and west [[Texas]] within the "Chinle Group".<ref name="LucasHuntHuber1990">{{cite journal |last1=Lucas |first1=S.G. |last2=Hunt |first2=A.P. |last3=Huber |first3=P. |year=1990 |title=Triassic stratigraphy in the Sangre de Cristo Mountains, New Mexico |url=https://nmgs.nmt.edu/publications/guidebooks/downloads/41/41_p0305_p0318.pdf |journal=New Mexico Geological Society Field Conference Guidebook |volume=41 |pages=305–318 }}</ref> This modified nomenclature is controversial; many still retain the Chinle as a formation and separate out the [[Dockum Group]].<ref name="lehman-1994">{{cite journal |last1=Lehman |first1=T.M. |year=1994 |title=The saga of the Dockum Group and the case of the Texas/New Mexico boundary fault |journal=New Mexico Bureau of Mines & Mineral Resources Bulletin |volume=150 |pages=37–51 |url=https://geoinfo.nmt.edu/publications/monographs/bulletins/downloads/150/B150.pdf }}</ref><ref name="cather-etal=2013">{{cite journal |last1=Cather |first1=S.M. |last2=Zeiger |first2=Kate E. |last3=Mack |first3=Greg H. |last4=Kelley |first4=Shari A. |year=2013 |title=Toward standardization of Phanerozoic stratigraphic nomenclature in New Mexico |url=https://www.researchgate.net/publication/275838662 |journal=Rocky Mountain Geology |volume=48 |issue=2 |page=101–124 |citeseerx=10.1.1.667.3513 |doi=10.2113/gsrocky.48.2.101 |bibcode=2013RMGeo..48..101C |s2cid=130158845 }}</ref> The Dockum was named in 1890, before the Chinle. Lucas also advocated abandoning the name '''Dolores Formation''' as a parochial synonym for the Chinle Group.
Overviews of the Chinle were created by Dubiel and others (1992) and Hintze and Axen (1995).<ref name="geolexreferences">[https://ngmdb.usgs.gov/Geolex/NewRefsmry/sumry_4997.html GEOLEX database bibliographic references for Chinle] (viewed 19 March 2006) </ref>
== Paleobiota == {{main|Paleobiota of the Chinle Formation}} The Chinle Formation is fossiliferous, with a diverse array of extinct reptile, fish, and plant fossils, including early dinosaurs and the famous petrified wood of [[Petrified Forest National Park]] in [[Arizona]].
==Stratigraphy== The formation members and their thicknesses are highly variable across the Chinle. {| class="wikitable" |+ Regional stratigraphic subunits of the Chinle Formation |- ! Arizona and western New Mexico !! North-central New Mexico !! Monument Valley and southern Utah !! Colorado and northeast Utah |- | [[Rock Point Member]]|| "siltstone member" (in part) || [[Church Rock Member]]|| rowspan="4" | "upper member" "red siltstone member"
"sandstone and conglomerate member" (UT)
"ocher siltstone member" (UT) |- | [[Owl Rock Member]]|| "siltstone member" (in part)? | [[Owl Rock Member]] Kane Springs beds (in part) |- | [[Petrified Forest Member]] ''sensu stricto'' / "Upper Petrified Forest" / Painted Desert Member |[[Petrified Forest Member]]|| [[Petrified Forest Member]] Kane Springs beds (in part) |- | [[Sonsela Member]]|| [[Poleo Formation]]|| [[Moss Back Member]] |- | [[Blue Mesa Member]] / "Lower Petrified Forest" [[Bluewater Creek Formation]] (NM) |[[Salitral Formation]]|| [[Monitor Butte Member]] [[Cameron Member]] | rowspan="2" |"mottled member" [[Gartra Member]]? |- |[[Mesa Redondo Member]] [[Shinarump Conglomerate]]
[[Zuni Mountains Formation]] (NM) | [[Agua Zarca Sandstone]] / [[Shinarump Conglomerate]] "mottled strata" |[[Shinarump Conglomerate]] [[Temple Mountain Member]] |}
=== Arizona and western New Mexico === [[File:Quartz-permineralized fossil wood (Chinle Formation, Upper Triassic; Petrified Forest, Arizona, USA) 1 (49004642997).jpg|thumb|[[Fossil wood]] from Chinle Formation exposures at Petrified Forest National Park ]]Some of the most extensive deposits of the Chinle Formation are found in the southern Colorado Plateau, including Arizona and the western portion of New Mexico. In this region, the oldest and stratigraphically lowest portion of the Chinle is the '''[[Shinarump Conglomerate]]'''. The Shinarump includes braided-river system channel-deposit [[facies]].<ref name="dubiel89" /> The Shinarump interfingers with a finer-grained subunit, the '''[[Mesa Redondo Member]]''',<ref name="RepenningEtal1969">{{cite journal |last1=Repenning |first1=C.A. |last2=Cooley |first2=M.E. |last3=Akers |first3=J.P. |year=1969 |title=Stratigraphy of the Chinle and Moenkopi Formations, Navajo and Hopi Indian Reservations, Arizona, New Mexico, and Utah |journal=U.S. Geological Survey Professional Paper |series=Professional Paper |volume=521-B |pages=B1–B34 |doi=10.3133/pp521B|doi-access=free }}</ref> one of the oldest widespread units in the badlands of the [[Painted Desert (Arizona)|Painted Desert]] area. In western New Mexico (particularly the [[Zuñi Mountains|Zuni Mountains]] area), the Mesa Redondo Member may be replaced by another sandy unit known as the '''[[Zuni Mountains Formation]]'''. Sediments from this time interval are followed by a geological unit called the '''[[Bluewater Creek Formation]]'''.<ref name="lucas-hayden-1989" /> [[File:Petrified Forest National Park- Araucarioxylon fossil wood weathered from the Chinle Formation.jpg|left|thumb|Petrified Forest National Park araucarioxylon fossil wood weathered from the Chinle Formation]] Most Chinle outcrops in the Painted Desert have traditionally been placed within the following '''[[Petrified Forest Member]]''', a segment of Triassic sediments which are so diverse and extensive that it is sometimes raised to its own formation, subdivided further, or redefined more narrowly. In its widest definition, the Petrified Forest Member (or Formation) is split into three sections: the muddy Lower Petrified Forest and Upper Petrified Forest, and the sandy Sonsela Sandstone bed, which separates them. The Lower "Petrified Forest Member" is generally known as the '''[[Blue Mesa Member]]'''.<ref name=":0">{{Cite book |last=Woody |first=Daniel T. |title=A century of research at Petrified Forest National Park: geology and paleontology |date=2006 |publisher=Museum of Northern Arizona |isbn=0-89734-120-1 |editor-last=Parker |editor-first=W.G. |chapter=Revised stratigraphy of the Lower Chinle Formation (Upper Triassic) of Petrified Forest National Park, Arizona |oclc=71015548 |editor-last2=Ash |editor-first2=S.R. |editor-last3=Irmis |editor-first3=R.B. |chapter-url=https://www.ldeo.columbia.edu/~polsen/cpcp/woody_06.pdf}}</ref> In [[Petrified Forest National Park]] (PEFO) and its vicinities, the Sonsela Sandstone is thick enough that it can be resolved into several distinct sandstone-rich layers. It is renamed as the '''[[Sonsela Member]]''' in this situation.<ref name=":0" /> The Sonsela Sandstone is a collection of braided-stream channel facies.<ref>{{Cite journal |last1=Martz |first1=Jeffrey W. |last2=Parker |first2=William G. |date=2010-02-19 |title=Revised Lithostratigraphy of the Sonsela Member (Chinle Formation, Upper Triassic) in the Southern Part of Petrified Forest National Park, Arizona |journal=PLOS ONE|language=en |volume=5 |issue=2 |article-number=e9329 |doi=10.1371/journal.pone.0009329 |issn=1932-6203 |pmc=2824835 |pmid=20174475|bibcode=2010PLoSO...5.9329M |doi-access=free }}</ref> The Upper "Petrified Forest Member" is sometimes called the Painted Desert Member,<ref name="lucas-2020">{{cite journal |last1=Lucas |first1=Spencer G. |title=Triassic stratigraphy of the southeastern Colorado Plateau, west-central New Mexico |journal=New Mexico Geological Society Special Publication |date=2020 |volume=14 |pages=123–133 |url=https://nmgs.nmt.edu/publications/special/14/NMGS_SP-14.pdf }}</ref> or simply referred to as the Petrified Forest Member in a more restricted definition of the term.<ref name=":0" /> The Petrified Forest is predominately overbank deposits with thin lenses of channel-deposit facies and lacustrine deposits.
The Petrified Forest Member grades into the '''[[Owl Rock Member]]''', a marginal lacustrine to lacustrine facies possibly representing a large lake system. The Owl Rock Member is followed by the youngest and sandiest subunit of the Chinle, the '''[[Rock Point Member]]'''. The Rock Point is distinct enough that it was previously considered a unit of the [[Wingate Sandstone]], a latest Triassic - early Jurassic aeolian formation which overlies the Chinle in many areas.<ref name="StewartEtal1972" />
=== Central New Mexico === [[File:Ghost Ranch NNL (Coelophysis Quarry) (35766606070).jpg|left|thumb|276x276px|The Whitaker ("''[[Coelophysis]]''") Quarry at [[Ghost Ranch]], preserving the "siltstone member" of the Chinle Formation]] Unambiguous exposures of the Chinle Formation extend into central New Mexico, beyond the eastern edge of the Colorado Plateau. Most of these are found in the [[Chama Basin]] of north-central New Mexico, particularly several famed paleontological sites at [[Ghost Ranch]] near [[Abiquiú, New Mexico|Abiquiu]]. Minor exposures also occur in the [[Lucero Uplift]] west of [[Albuquerque, New Mexico|Albuquerque]], as well as other areas along the [[Rio Grande rift|Rio Grande Rift]].<ref name="Lucas1991">{{cite journal |last1=Lucas |first1=S.G. |year=1991 |title=Triassic stratigraphy, paleontology and correlation, south-central New Mexico |url=https://nmgs.nmt.edu/publications/guidebooks/downloads/42/42_p0243_p0259.pdf |journal=New Mexico Geological Society Field Conference Guidebook |volume=42 |pages=243–253 }}</ref><ref name=":2">{{Cite journal |last1=Zeigler |first1=Kate E. |last2=Kelley |first2=Shari |last3=Geissman |first3=John W. |date=2008-01-01 |title=Revisions to stratigraphic nomenclature of the Upper Triassic Chinle Group in New Mexico: New insights from geologic mapping, sedimentology, and magnetostratigraphic/paleomagnetic data |journal=Rocky Mountain Geology |volume=43 |issue=2 |pages=121–141 |doi=10.2113/gsrocky.43.2.121 |bibcode=2008RMGeo..43..121Z |issn=1555-7332}}</ref><ref name="StewartEtal1972" />[[File:Hayden Quarry.png|thumb|315x315px|Stratigraphic column (A) and outcrop photos (C) of the Hayden Quarry [[fossil locality]] at [[Ghost Ranch]], NM, alongside a map of Chinle exposures in NM (B)]]As in the Colorado Plateau, the lowest major unit in north-central New Mexico is a sandstone-rich member. This layer, the '''[[Agua Zarca Sandstone]]''',<ref name="WoodNorthrop1946" /> is often synonymized with the Shinarump Conglomerate,<ref name="LucasEtal2005">{{cite journal |last1=Lucas |first1=Spencer G. |last2=Zeigler |first2=Kate E. |last3=Heckert |first3=Andrew B. |last4=Hunt |first4=Adrian P. |date=2005 |title=Review of Upper Triassic stratigraphy and biostratigraphy in the Chama Basin, northern New Mexico |url=https://nmgs.nmt.edu/publications/guidebooks/downloads/56/56_p0170_p0181.pdf |journal=New Mexico Geological Society Field Conference Series |volume=56 |pages=170–181 }}</ref><ref name=":2" /><ref name="lucas-2020" /> though it may be derived from a different erosional source.<ref name="cather-etal=2013" /> It is often preceded by a very thin layer of silty mottled strata. This mottled strata is sometimes termed the Zuni Mountains Formation,<ref name="LucasEtal2005" /><ref name="lucas-2020" /> though the application of this term beyond the Zuni Mountains is questionable.<ref name=":2" /><ref name="cather-etal=2013" /> In the Chama Basin at least, the mottled strata is derived from the eroded and [[Pedogenesis|pedogenically]] modified surface of the Moenkopi Formation.<ref name="cather-etal=2013" />
The coarse lower unit grades into the fine-grained '''[[Salitral Formation]]''', which is equivalent to the Blue Mesa Member and Bluewater Creek Formation. In south-central New Mexico, it may instead grade into the '''[[San Pedro Arroyo Formation]]''', a similar heterolithic unit.<ref name="Lucas1991" /> Coarse sandstone returns along a sharp contact with the following '''[[Poleo Formation]]''', an equivalent of the Sonsela Member.<ref name=":2" /> The Poleo Formation grades into the thick colorful sediments of the Petrified Forest Member. Authors which raise this member to a formation subdivide it into the lower Mesa Montosa Member and the upper Painted Desert Member.<ref name="LucasEtal2005" /><ref name=":2" /> The Petrified Forest Member is fossiliferous in the Chama Basin, with major sites including the Hayden, Canjilon, and Snyder quarries of Ghost Ranch.<ref>{{Cite journal |last1=Irmis |first1=Randall B. |last2=Nesbitt |first2=Sterling J. |last3=Padian |first3=Kevin |last4=Smith |first4=Nathan D. |last5=Turner |first5=Alan H. |last6=Woody |first6=Daniel |last7=Downs |first7=Alex |date=2007-07-20 |title=A Late Triassic Dinosauromorph Assemblage from New Mexico and the Rise of Dinosaurs |url=https://www.researchgate.net/publication/6197829 |journal=Science |language=en |volume=317 |issue=5836 |pages=358–361 |doi=10.1126/science.1143325 |pmid=17641198 |bibcode=2007Sci...317..358I |s2cid=6050601 |issn=0036-8075}}</ref>
The stratigraphically highest unit in north-central New Mexico is the informally-named "'''siltstone member'''". This unit is best exposed at Ghost Ranch, where it has produced the famous Whitaker Quarry, also known as the ''Coelophysis'' quarry due to a high concentration of fossils belonging to the [[Theropoda|theropod]] [[dinosaur]] ''[[Coelophysis bauri]]''. The "siltstone member" may be equivalent to the Rock Point Member, and some authors refer to it as such.<ref name="LucasEtal2005" /><ref name=":2" /><ref name="lucas-2020" />
=== Monument Valley and southern Utah === [[File:Monument Valley 04.jpg|thumb|The [[Shinarump Conglomerate]] (top, horizontal layers) as an erosion-resistant cap rock in [[Monument Valley]]]] [[Image:SEUtahStrat.JPG|thumb|300px|[[Permian]] through [[Jurassic]] stratigraphy of [[Glen Canyon National Recreation Area]] in Utah.<br />From top to bottom: (youngest to oldest)<br />5{{snd}}Rounded tan domes of the [[Navajo Sandstone]], <br />4{{snd}}layered red [[Kayenta Formation]], <br />3{{snd}}cliff-forming, vertically jointed, red [[Wingate Sandstone]], <br />2{{snd}}slope-forming, purplish Chinle Formation, layered, lighter-red [[Moenkopi Formation]]<br />1{{snd}}white, layered [[Cutler Formation]] sandstone.<br />Picture from [[Glen Canyon National Recreation Area]], Utah|left]]The Chinle continues northwards into southern Utah and the Four Corners area, though it thins greatly to the northwest. A narrow band of undifferentiated purplish sediments from the lower part of the formation extend into vicinity of [[St. George, Utah|St. George]]. The formation thickens eastward into [[Zion National Park]] and [[Grand Staircase–Escalante National Monument]]. The Chinle is a prominent component of badlands and outcrops in the various national parks, monuments, and recreation areas of southeast Utah, extending in a discontinuous patchwork up to the [[San Rafael Swell]].<ref name="Dubiel1987">{{cite journal |last1=Dubiel |first1=R.F. |year=1987 |title=Sedimentology and new fossil occurrences of the Upper Triassic Chinle Formation, southeastern Utah |url=https://archives.datapages.com/data/fcgs/data/018/018001/99_four-corners180099.htm |journal=Four Corners Geological Society Field Conference Guidebook |volume=10 |pages=99–107 }}</ref><ref name=":1">{{Cite journal |last1=Martz |first1=Jeffrey |last2=Kirkland |first2=James |last3=Milner |first3=Andrew |last4=Parker |first4=William |last5=Santucci |first5=Vincent |date=2017-04-21 |title=Upper Triassic lithostratigraphy, depositional systems, and vertebrate paleontology across southern Utah |url=http://giw.utahgeology.org/giw/index.php/GIW/article/view/16 |journal=Geology of the Intermountain West |language=en |volume=4 |pages=99–180 |doi=10.31711/giw.v4.pp99-180 |issn=2380-7601|doi-access=free }}</ref> The stratigraphic nomenclature used in southern Utah is also utilized in [[Monument Valley]], where the coarse-grained lower members of the Chinle form a caprock for many famous buttes which characterize the valley.<ref name="StewartEtal1972" />
In this region, the stratigraphically lowest unit in the Chinle is usually the Shinarump Conglomerate (or Shinarump Member), which thins northward but is a reliable component of outcrops throughout the region. In several areas, a thin layer of mottled [[Paleosol|paleosols]], the '''[[Temple Mountain Member]]''', may be superimposed onto the Shinarump and underlying Moenkopi Formation.<ref name="OSullivanMacLachlan1975">{{cite journal |last1=O'Sullivan |first1=R.B. |last2=MacLachlan |first2=M.E. |year=1975 |title=Triassic rocks of the Moab-White Canyon area, southeastern Utah |url=https://archives.datapages.com/data/fcgs/data/013/013001/129_four-corners130129.htm |journal=Four Corners Geological Society Field Conference Guidebook, 8th Field Conference |pages=129–141 |number=8}}</ref><ref name=":1" /><ref>{{cite web | url = https://3dparks.wr.usgs.gov/coloradoplateau/lexicon/chinle_shinarump.htm | title = Shinarump Member of Chinle Formation | access-date = 2011-01-10 | date = 2006-05-06 | work = Colorado River Basin Stratigraphy | publisher = USGS}}</ref>
The '''[[Monitor Butte Member]]''' overlies the Shinarump and Temple Mountain members in southeast Utah and Monument Valley. This unit comprises drab and generally fine-grained sediments, equivalent to the Blue Mesa Member and Bluewater Creek Formation found further south.<ref name=":1" /> The facies of this interval have been interpreted as overbank (distal [[floodplain]]) and [[Lake|lacustrine]] deposits. At Zion National Park, the Monitor Butte Member is replaced by a thick time-equivalent unit, the '''[[Cameron Member]]''', which is also found in the Navajo Nation near its namesake of [[Cameron, Arizona]]. The Cameron Member is practically identical to the Blue Mesa Member, and likely represents the same depositional environment along the ancient river system responsible for the Chinle Formation. It is also distinct from the Monitor Butte Member, which has more evaporite deposits and fewer red sandy layers.<ref name="Lucas1993" /><ref name=":1" />
The drab mudstone of the Monitor Butte and Cameron members are succeeded in a few areas by a thin section of massive conglomeratic sandstone, the '''[[Moss Back Member]]'''. This member represents sandy river channel deposits and is likely equivalent to part of the Sonsela Member.<ref name=":1" /> Elsewhere, the Monitor Butte grades into the Petrified Forest Member, which in Utah includes the thin but geographically extensive Correo Sandstone Bed. The Petrified Forest Member is followed by the Owl Rock Member.<ref name=":1" /><ref name="lucas-hayden-1989" /> A unit of drab interbedded coarse and fine sediments, the '''Kane Springs beds''', develops in the Paradox Basin. The Kane Springs beds are river deposits which are likely equivalent to the Owl Rock Member and the upper part of the Petrified Forest Member.<ref name=":1" /> Finally, either the Rock Point Member or '''[[Church Rock Member]]''' overlie the Owl Rock. Some researchers feel that the Church Rock and Rock Point members may be synonymous.<ref>{{cite journal |last1=Milner |first1=A.R. |year=2006 |title=Plant fossils from the Owl Rock or Church Rock Members, Chinle Formation, San Juan County, Utah |journal=New Mexico Museum of Natural History and Science Bulletin |volume=37 |pages=410–413 |url=https://books.google.com/books?id=ulvmCQAAQBAJ&pg=PA410}}</ref> They are complex heterolithic units, representing variously braided-river facies, lacustrine, and overbank deposits. == Chronology ==
=== Tetrapod biostratigraphy === {{main|Triassic land vertebrate faunachrons}} The Chinle Formation is entirely [[Late Triassic]] in age. Tetrapod biostratigraphy for the Chinle was first developed based on [[Phytosaur|phytosaurs]] and [[Aetosaur|aetosaurs]], which in 1998 were combined into global biozones in [[Spencer G. Lucas]]'s [[Land Vertebrate Faunachron]]s system.<ref name=":02">{{Cite journal |last=Lucas |first=Spencer G |date=1998-11-01 |title=Global Triassic tetrapod biostratigraphy and biochronology |url=http://www.sciencedirect.com/science/article/pii/S0031018298001175 |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |language=en |volume=143 |issue=4 |pages=347–384 |doi=10.1016/S0031-0182(98)00117-5 |bibcode=1998PPP...143..347L |issn=0031-0182|url-access=subscription }}</ref> Simplified [[stratigraphy]] based on Litwin.<ref>Litwin, R.J., Traverse, A., and Ash, S.R., 1991. Preliminary palynological zonation of the Chinle Formation, southwestern U.S.A., and its correlation to the Newark Supergroup (eastern U.S.A.). Review of Paleobotany and Palynology, v. 77, pp. 269–287.</ref> Note that age inferences devised by Lucas do not necessarily align with other chronological methods used in the Chinle Formation. Other works on Chinle biostratigraphy, such as Martz & Parker (2017),<ref name=":82">{{Citation |last1=Martz |first1=J. W. |title=Revised Formulation of the Late Triassic Land Vertebrate "Faunachrons" of Western North America: Recommendations for Codifying Nascent Systems of Vertebrate Biochronology |date=2017-01-01 |url=https://www.sciencedirect.com/science/article/pii/B9780128032435000029 |work=Terrestrial Depositional Systems |pages=39–125 |editor-last=Zeigler |editor-first=Kate E. |publisher=Elsevier |language=en |isbn=978-0-12-803243-5 |last2=Parker |first2=W. G. |editor2-last=Parker |editor2-first=William G.}}</ref> are better integrated with magnetostratigraphy and radiometric dating, and are considered more accurate. {| class="wikitable" |- ! [[Faunachron]] name !Distinguishing taxa !Estimated age according to [[radiometric dating]] and [[magnetostratigraphy]] !Inferred age based on Lucas's global tetrapod correlations ! Representative Chinle Member(s) |- | [[Apachean (biochronology)|'''<u>Apachean</u>''']] |''[[Redondasaurus]]'' |[[Rhaetian]] (207–202 Ma) | late [[Norian]] – [[Rhaetian]] | * [[Rock Point Member|Rock Point]] / [[Church Rock Member|Church Rock]] * "siltstone member" * [[Owl Rock Member|Owl Rock]] (in part)? |- | '''<u>[[Revueltian]]</u>''' |''[[Typothorax coccinarum]]'', ''[[Machaeroprosopus]]'' |middle to late Norian (Alaunian to [[Sevatian]], 215–207 Ma) | early to middle Norian | * [[Owl Rock Member|Owl Rock]] (in part)? * Kane Springs Beds? * [[Petrified Forest Member|Petrified Forest]] ("Upper Petrified Forest" / Painted Desert) * [[Sonsela Member|Sonsela]] (in part) |- | '''<u>[[Adamanian]]</u>''' |Basal [[Leptosuchomorpha|leptosuchomorph]] phytosaurs (''[[Smilosuchus]]'', ''[[Leptosuchus]]'', etc.) |early to middle Norian (Lacian to early [[Alaunian]], 224–215 Ma) | upper Late [[Carnian]] | * [[Sonsela Member|Sonsela]] (in part) * [[Blue Mesa Member|Blue Mesa]] ("Lower Petrified Forest") * [[Moss Back Member|Moss Back]] * [[Monitor Butte Member|Monitor Butte]] * [[Cameron Member|Cameron]] (in part) |- | '''<u>[[Otischalkian]]</u>''' |Basal phytosaurs (''[[Paleorhinus]]'' / ''[[Parasuchus]]'') |earliest [[Norian]] (earliest [[Lacian]], 227–224 Ma) | lower Late Carnian | * [[Cameron Member|Cameron]] (in part) * [[Mesa Redondo Member|Mesa Redondo]] * [[Shinarump Conglomerate|Shinarump]] * [[Temple Mountain Member|Temple Mountain]] |}
=== Radiometric dating === Since 2011, widespread [[radiometric dating]] has helped to refine precise age data for part of the Chinle Formation, particularly in areas with a more complete stratigraphic record such as Petrified Forest National Park (PEFO). Volcanism further southwest along the [[Cordilleran magmatic arc]] supplies [[zircon]] crystals to the Chinle system, allowing for [[Uranium–lead dating|U-Pb dating]] of layers which host zircon grains. Eroded sediments from the [[Ancestral Rocky Mountains]], [[Ouachita Mountains]] and [[Mogollon Highlands]] also supply older reworked zircon to the basin.<ref name=":4">{{Cite journal |last1=Gehrels |first1=George |last2=Giesler |first2=Dominique |last3=Olsen |first3=Paul |last4=Kent |first4=Dennis |last5=Marsh |first5=Adam |last6=Parker |first6=William |last7=Rasmussen |first7=Cornelia |last8=Mundil |first8=Roland |last9=Irmis |first9=Randall |last10=Geissman |first10=John |last11=Lepre |first11=Christopher |date=2020-09-23 |title=LA-ICPMS U–Pb geochronology of detrital zircon grains from the Coconino, Moenkopi, and Chinle formations in the Petrified Forest National Park (Arizona) |url=https://gchron.copernicus.org/articles/2/257/2020/ |journal=Geochronology |language=English |volume=2 |issue=2 |pages=257–282 |doi=10.5194/gchron-2-257-2020|bibcode=2020GeChr...2..257G |s2cid=236890628 |doi-access=free |hdl=10150/663492 |hdl-access=free }}</ref>
Chinle radiometric dating is complicated by lithological quirks of zircon deposition. Taken at face value, U-Pb dates from coarse-grained layers are often several million years older than expected based on magnetostratigraphy, while mud-dominated layers are generally more accurate despite a lower sample size. This is likely because sandy rivers receive a higher proportion of recycled zircon grains from distant eroded rocks, while muddy plains are supplied with fresh zircon-rich ash from contemporary volcanic eruptions. While zircons from sandstone-rich layers are less useful for inferring direct depositional ages, they can be very useful for inferring sediment sources: each igneous or metamorphic sediment source has its own set of old (usually Precambrian) zircon ages, which can be traced in Triassic sediments.<ref name=":4" />
Outcrops of the [[Mesa Redondo Member]] at PEFO have been dated to ~225 Ma (2011)<ref name=":5">{{Cite journal |last1=Ramezani |first1=Jahandar |last2=Hoke |first2=Gregory D. |last3=Fastovsky |first3=David E. |last4=Bowring |first4=Samuel A. |last5=Therrien |first5=François |last6=Dworkin |first6=Steven I. |last7=Atchley |first7=Stacy C. |last8=Nordt |first8=Lee C. |date=2011-11-01 |title=High-precision U-Pb zircon geochronology of the Late Triassic Chinle Formation, Petrified Forest National Park (Arizona, USA): Temporal constraints on the early evolution of dinosaurs |journal=GSA Bulletin |volume=123 |issue=11–12 |pages=2142–2159 |doi=10.1130/B30433.1 |bibcode=2011GSAB..123.2142R |issn=0016-7606}}</ref> or ~228 Ma (2013),<ref name=":7">{{Cite journal |last1=Atchley |first1=Stacy C. |last2=Nordt |first2=Lee C. |last3=Dworkin |first3=Stephen I. |last4=Ramezani |first4=Jahandar |last5=Parker |first5=William G. |last6=Ash |first6=Sidney R. |last7=Bowring |first7=Samuel A. |date=2013-12-01 |title=A Linkage Among Pangean Tectonism, Cyclic Alluviation, Climate Change, and Biologic Turnover in the Late Triassic: The Record From The Chinle Formation, Southwestern United States |journal=Journal of Sedimentary Research |volume=83 |issue=12 |pages=1147–1161 |doi=10.2110/jsr.2013.89 |issn=1527-1404}}</ref> though these may be influenced by recycled grains.<ref name=":4" /> Later estimates from a major [[Core drill|core drilling]] project support a more recent depositional age of 223–222 Ma (2020).<ref name=":6">{{Cite journal |last1=Rasmussen |first1=Cornelia |last2=Mundil |first2=Roland |last3=Irmis |first3=Randall B. |last4=Geisler |first4=Dominique |last5=Gehrels |first5=George E. |last6=Olsen |first6=Paul E. |last7=Kent |first7=Dennis V. |last8=Lepre |first8=Christopher |last9=Kinney |first9=Sean T. |last10=Geissman |first10=John W. |last11=Parker |first11=William G. |date=2020-07-20 |title=U-Pb zircon geochronology and depositional age models for the Upper Triassic Chinle Formation (Petrified Forest National Park, Arizona, USA): Implications for Late Triassic paleoecological and paleoenvironmental change |journal=GSA Bulletin |volume=133 |issue=3–4 |pages=539–558 |doi=10.1130/B35485.1 |issn=0016-7606}}</ref><ref name=":4" /> This firmly suggests that practically all of the Chinle Formation was deposited in the [[Norian]] stage; According to the consensus "long Norian" hypothesis and radiometric assessments of marine strata, the Carnian-Norian boundary is tentatively set to ~227 Ma.<ref name=":3">{{Cite journal |last1=Ogg |first1=James G. |last2=Huang |first2=Chunju |last3=Hinnov |first3=Linda |date=May 2014 |title=Triassic timescale status: a brief overview |url=https://albertiana-sts.org/wp-content/uploads/2017/06/Albertiana_41.pdf#page=5 |journal=Albertiana |volume=41 |pages=3–30}}</ref>
At PEFO, U-Pb estimates from the [[Blue Mesa Member]] include 223 Ma (2011),<ref name=":5" /> 222 Ma (2020),<ref name=":6" /> and 221–218 Ma (2020).<ref name=":4" /> Dated outcrops of drab mudstone near [[St. Johns, Arizona]] fit this general time period as well. The fossiliferous ''Placerias'' quarry, previously regarded as belonging to an older subunit, is likely part of the Blue Mesa Member based on an age date of 219.4 Ma (2014).<ref name=":8">{{Cite journal |last1=Ramezani |first1=Jahandar |last2=Fastovsky |first2=David E. |last3=Bowring |first3=Samuel A. |date=2014-06-01 |title=Revised chronostratigraphy of the Lower Chinle Formation strata in Arizona and New Mexico (USA): High-precision U-Pb geochronological constraints on the Late Triassic evolution of dinosaurs |url=https://www.ajsonline.org/content/314/6/981 |journal=American Journal of Science |language=en |volume=314 |issue=6 |pages=981–1008 |doi=10.2475/06.2014.01 |bibcode=2014AmJS..314..981R |s2cid=129675146 |issn=0002-9599|url-access=subscription }}</ref> At Six Mile Canyon near [[Fort Wingate, New Mexico]], the base of the Blue Mesa Member (or its local equivalent) is defined by a distinct sandstone bed, which has been dated to 221–219 Ma (2009)<ref name=":9" /> or 218 Ma (2011).<ref name=":10">{{Cite journal |last1=Irmis |first1=Randall B. |last2=Mundil |first2=Roland |last3=Martz |first3=Jeffrey W. |last4=Parker |first4=William G. |date=2011-09-15 |title=High-resolution U–Pb ages from the Upper Triassic Chinle Formation (New Mexico, USA) support a diachronous rise of dinosaurs |url=https://www.sciencedirect.com/science/article/pii/S0012821X11004316 |journal=Earth and Planetary Science Letters |language=en |volume=309 |issue=3 |pages=258–267 |doi=10.1016/j.epsl.2011.07.015 |bibcode=2011E&PSL.309..258I |issn=0012-821X|url-access=subscription }}</ref> The underlying [[Bluewater Creek Formation]] has also been dated to 221–219 Ma (2014), suggesting that it overlaps in time with the Arizonan Blue Mesa Member and possibly part of the Sonsela Member.<ref name=":8" />
Radiometric dates are well-recorded for the [[Sonsela Member]], though a high concentration of reworked zircons must be accounted for when inferring an accurate age of deposition. The true duration of the Sonsela Member is likely from around 218 Ma to 213 Ma (2020),<ref name=":6" /><ref name=":4" /> though older estimates place its base at 220–219 Ma (2011, 2013).<ref name=":5" /><ref name=":7" /> A prominent biological turnover is found at the Adamanian-Revueltian boundary in the middle of the Sonsela Member, around 214 Ma. It may correspond to a local extinction, or simply represents a time period which is truncated by slow deposition or a geological hiatus.<ref>{{Cite journal |last1=Nordt |first1=Lee |last2=Atchley |first2=Stacy |last3=Dworkin |first3=Steve |date=2015-11-01 |title=Collapse of the Late Triassic megamonsoon in western equatorial Pangea, present-day American Southwest |journal=GSA Bulletin |volume=127 |issue=11–12 |pages=1798–1815 |doi=10.1130/B31186.1 |bibcode=2015GSAB..127.1798N |issn=0016-7606}}</ref><ref name=":6" /> The thin Sonsela Sandstone bed, the namesake of its corresponding member, has been dated to 216.6 Ma (2019) at its type locality at Sonsela Buttes in Arizona.<ref>{{Cite journal |last1=Marsh |first1=Adam D. |last2=Parker |first2=William G. |last3=Stockli |first3=Daniel F. |last4=Martz |first4=Jeffrey W. |date=2019-05-08 |title=Regional correlation of the Sonsela Member (Upper Triassic Chinle Formation) and detrital U-Pb zircon data from the Sonsela Sandstone bed near the Sonsela Buttes, northeastern Arizona, USA, support the presence of a distributive fluvial system |journal=Geosphere |volume=15 |issue=4 |pages=1128–1139 |doi=10.1130/GES02004.1 |bibcode=2019Geosp..15.1128M |s2cid=164325311 |issn=1553-040X|doi-access=free }}</ref>
The first Chinle U-Pb age data to be published referred to the Black Forest Bed, a sandstone layer near the top of the [[Petrified Forest Member]] in PEFO. U-Pb estimates for this layer include ~213 Ma (2003 maximum),<ref>{{Cite journal |last1=Riggs |first1=N.R. |last2=Ash |first2=S.R. |last3=Barth |first3=A.P. |last4=Gehrels |first4=G.E. |last5=Wooden |first5=J.L. |date=2003-11-01 |title=Isotopic age of the Black Forest Bed, Petrified Forest Member, Chinle Formation, Arizona: An example of dating a continental sandstone |journal=GSA Bulletin |volume=115 |issue=11 |pages=1315–1323 |doi=10.1130/B25254.1 |bibcode=2003GSAB..115.1315R |issn=0016-7606}}</ref> ~211 Ma (2009),<ref name=":9">{{Cite journal |last1=Heckert |first1=A.B. |last2=Lucas |first2=S.G. |last3=Dickinson |first3=W.R. |last4=Mortensen |first4=J.K. |date=2009 |title=New ID-TIMS U-Pb ages for Chinle Group strata (Upper Triassic) in New Mexico and Arizona, correlation to the Newark Supergroup, and Implications for the "long Norian" |journal=Geological Society of America Abstracts with Programs |volume=41 |issue=7 |page=123}}</ref> and ~210 Ma (2011, 2020).<ref name=":5" /><ref name=":6" /><ref name=":4" /> A presumably older exposure of the Petrified Forest Member, the Hayden Quarry at Ghost Ranch, is dated to 212 Ma (2011).<ref name=":10" /> A similar age was found for the middle part of the member in PEFO.<ref name=":4" /> The end of the Petrified Forest Member was probably close to 208 Ma, meaning that overlying strata is presumably latest Norian-Rhaetian in age.<ref name=":5" /><ref name=":6" />
==Places found== [[File:Canyonlands strat.jpg|thumb|[[Stratigraphy]] of [[Canyonlands National Park|Canyonlands N.P.]], with members of the Chinle Formation]]Geologic Province:<ref name="geolexdatabase" /> [[File:Glen Canyon Sandstone over Chinle Formation (Dinosaur National Monument, Utah, USA) 9 (48872761577).jpg|thumb|[[Glen Canyon Sandstone]] over Chinle Formation ([[Dinosaur National Monument]], [[Utah]])]]{{col-list| *[[Black Mesa Basin]]*<ref name=Dubiel1989a>{{cite journal |last1=Dubiel |first1=R.F. |year=1989 |title=Sedimentology and revised nomenclature of the Upper Triassic Chinle Formation and the Lower Jurassic Wingate Sandstone, northwestern New Mexico and northeastern Arizona |journal=New Mexico Geological Society Field Conference Guidebook |volume=40 |pages=213–223 |url=https://nmgs.nmt.edu/publications/guidebooks/downloads/40/40_p0213_p0223.pdf }}</ref><ref name=RepenningEtal1969/> ::Rock Point Member ::Owl Rock Member ::Petrified Forest Member ::Mesa Redondo Member ::Shinarump Member *[[Great Basin]] province*<ref>{{cite journal |last1=Hintze |first1=L.F. |last2=Axen |first2=G.J. |year=1995 |title=Geologic map of the Scarecrow Peak Quadrangle, Washington County, Utah, and Lincoln County, Nevada |journal=U.S. Geological Survey Geologic Quadrangle Map |volume=GQ-1759 |url=https://ngmdb.usgs.gov/Prodesc/proddesc_307.htm }}</ref> ::Petrified Forest Member ::Shinarump Member *[[Green River Basin]]*<ref name=PooleStewart1964>{{cite journal |last1=Poole |first1=F.G. |last2=Stewart |first2=J.H. |year=1964 |title=Chinle Formation and Glen Canyon Sandstone in northeastern Utah and northwestern Colorado |journal=U.S. Geological Survey Professional Paper |volume=501-D |pages=D30–D39 |doi=10.3133/pp501D|doi-access=free }}</ref> ::upper member ::red siltstone member (possibly correlative with Church Rock Member) ::local sandstone and conglomerate member ::ochre siltstone member ::mottled member ::Gartra Member *[[Las Vegas-Raton Basin]]*<ref name=LucasHuntHuber1990/> (disputed<ref name="lehman-1994"/><ref name="cather-etal=2013"/>) ::Redonda Formation ::Bull Canyon Formation ::Trujillo Formation ::Garita Creek Formation *[[Orogrande Basin]]<ref name=Lucas1991/> ::San Pedro Arroyo Formation ::Shinarump Formation *[[Palo Duro Basin]]* (undivided<ref name=Barnes1983>{{cite book |editor-last1=Barnes |editor-first1=V.E. |year=1983 |title=Geologic atlas of Texas |chapter=Tucumcari sheet |publisher=University of Texas-Austin, Bureau of Economic Geology}}</ref>) *[[Paradox Basin]]*<ref name=Dubiel1987/> ::Church Rock Member ::Owl Rock Member ::Petrified Forest Member ::Moss Back Member ::Monitor Butte Member ::Shinarump Conglomerate *[[Permian Basin (North America)|Permian Basin]] (undivided<ref name=Barnes1983/>) *[[Piceance Basin]]*<ref name=PooleStewart1964/> ::upper member ::red siltstone member (possibly correlative with Church Rock Member) ::local sandstone and conglomerate member ::ochre siltstone member ::mottled member ::Gartra Member *[[Plateau Sedimentary Province]]*<ref name=Dubiel1989a/><ref name=RepenningEtal1969/> ::Rock Point Member ::Owl Rock Member ::Petrified Forest Member ::Mesa Redondo Member ::Shinarump Member *[[San Juan Basin]]*<ref>{{cite journal |last1=Lucas |first1=Spencer G. |title=Triassic stratigraphy of the southeastern Colorado Plateau, west-central New Mexico |journal=New Mexico Geological Society Field Conference Series |date=2021 |volume=72 |pages=229–240 |url=https://nmgs.nmt.edu/publications/guidebooks/downloads/71/71_p0229_p0240.pdf }}</ref> ::Rock Point Formation ::Owl Rock Formation ::Petrified Forest Formation ::Bluewater Creek/San Pedro Arroyo Formations ::Shinarump Conglomerate/[[Zuni Mountains Formation]] *[[Sierra Grande Uplift]]* (undivided<ref name=Barnes1983/>) *[[Uinta Basin]]*<ref name="sikitch-1965"/> ::Stanaker Member ::Gartra Member *[[Uinta Uplift]]*<ref name="sikitch-1965"/> ::Stanaker Member ::Gartra Member *[[Wasatch Uplift]]*<ref name=StewartEtal1972/> }}
Parklands: *[[Arches National Park]] *[[Canyonlands National Park]] – see [[geology of the Canyonlands area]] *[[Capitol Reef National Park]] – see [[geology of the Capitol Reef area]] *[[Colorado National Monument]] *[[Dinosaur National Monument]] *[[Flaming Gorge National Recreation Area]] *[[Glen Canyon National Recreation Area]] *[[Gold Butte National Monument]] *[[Grand Canyon National Park]] – see [[geology of the Grand Canyon]] *[[Grand Staircase–Escalante National Monument]] *[[Lake Mead National Recreation Area]] *[[Natural Bridges National Monument]] *[[Petrified Forest National Park]] *[[Red Fleet State Park]] *[[Wupatki National Monument]] *[[Zion National Park]] – see [[geology of the Zion and Kolob canyons area]] *[[Red Rock Canyon National Conservation Area]]
Other: *[[Ghost Ranch]]<ref>{{Cite web |url=https://3dparks.wr.usgs.gov/coloradoplateau/ |title=Park stratigraphy of the Colorado Plateau |archive-date=1 April 2009 |archive-url=https://web.archive.org/web/20090401142727/http://3dparks.wr.usgs.gov/coloradoplateau/ }}</ref>
==See also== * [[List of dinosaur-bearing rock formations]] * [[Paleobiota of the Chinle Formation]] * [[Triassic land vertebrate faunachrons]]
==References== {{Reflist}}
==Further reading== * Lucas, S. G. (November 1998). [https://www.sciencedirect.com/science/article/abs/pii/S0031018298001175 "Global Triassic tetrapod biostratigraphy and biochronology"]. ''Palaeogeography, Palaeoclimatology, and Palaeoecology'', '''143''':4, pp. 347–384.
==External links== {{Commons category|Chinle Formation}} * [https://web.archive.org/web/20110720114717/http://macrostrat.geology.wisc.edu/unit_info.php?name_id=380 Spatial distribution of Chinle in Macrostrat] * [https://chinleana.blogspot.com/2008/11/chinle-confusion.html Chinleana- "Chinle Confusion"]
{{Chronostratigraphy of Colorado|Mesozoic state=expanded}}
[[Category:Chinle Formation| ]] [[Category:Geologic formations of Nevada]] [[Category:Geologic formations of Utah]] [[Category:Triassic Arizona]] [[Category:Triassic Colorado]] [[Category:Triassic formations of New Mexico]] [[Category:Mudstone formations of the United States]] [[Category:Sandstone formations of the United States]] [[Category:Siltstone formations of the United States]]