Talk:Chinle Formation

Redirects: Chinle formation, Chinle Group, Chinle group Disambiguation: Chinle --

Fauna of the Chinle Formation
Recent studies (Irmis et. al., 2007; Parker et. al., 2005) demonstrate that all putative ornithischians from the Chinle Formation (Crosbysaurus, Krzyzanowskisaurus, Lucianosaurus, Protecovasaurus, Revueltosaurus,Tecovasaurus) are either misidentified pseudosuchians or indeterminate archosauriforms. None of these genera possess a basal asymmetric swelling ("cingulum"), as discussed by Irmis et. al. and Parker et. al. Furthermore, alleged ornithischian synapomorphies of Revueltosaurus and other above-mentioned genera are also found throughout Archosauria (Parker et. al., 2005).

Eucoelophysis baildwini is longer considered a coelophysoid theropod, but instead is a non-dinosarian dinosauriform (Ezcurra, 2006; Nesbitt et. al., 2007). The types of Coelophysis bauri, C. longicollis, and C. willistoni, however, remain coelophysoid theropods (see Nesbitt et. al., 2007 for supporting characters). Indeterminate coelophysoid material from the Snyder Quarry referred to Eucoelophysis sp. by Heckert. et. al. (2000, 2003) is instead referrable to Coelophysis bauri (Spielmann et. al., 2007).

Indeterminate herrerasaurid remains from the Cooper Canyon Formation are based on specimens described and referred to Chindesaurus by Long and Murry (1995; see also Hunt, 1994, 2001 and Hunt et. al., 1998). The indeterminate ceratosaur from the Cooper Canyon Formation mentioned by Weishampel et. al. refers to numerous specimens (e.g. NMMNH P-16656, NMMNH P-17258) from the Barranca/Revuelto badlands of Quay County (=Revueltoraptor lucasi Hunt, 1994; Herrerasauridae gen et. sp. nov. 1 [Hunt, 2001]; Herrerasaurid A [Hunt. et. al., 1998]) and a partial skeleton (NMMNH P-4569) from Guadalupe County (=Comanchesaurus kuesi Hunt, 1994; Herrerasauridae gen. et. sp. nov. 2 [Hunt, 2001]; Herrerasaurid B [Hunt. et. al., 1998]). These specimens are now considered to be unidentified saurischians (Nesbitt et. al., 2007). A partial skeleton (NMMNH P-17375) from the Cooper Canyon Formation of Quay County, New Mexico(=Cryptoraptor lockleyi Hunt, 1994; Theropoda gen. et. sp. nov. 3 [Hunt, 2001]; "small theropod of unknown affinties" [Hunt et. al., 1998]) represents a non-dinosaurian archosaur aligned with Shuvosauridae (Nesbitt et. al., 2007).

Heckert, A.B., Zeigler, K.E., Lucas, S.G., Rinehart, L.F., and Harris, J.D. 2000. Preliminary description of coelophysoids (Dinosauria: Theropoda) from the Upper Triassic (Revueltian: early-mid Norian) Snyder Quarry, north-central New Mexico, pp. 27-32 in Lucas, S.G. and Heckert, A.B. (eds.). Dinosaurs of New Mexico.

Hunt, Adrian P. 1994. Vertebrate paleontology and biostratigraphy of the Bull Canyon Formation (Chinle Group, Upper Triassic), east-central New Mexico with revisions of the families Metoposauridae (Amphibia: Temnospondyli) and Parasuchidae (Reptilia:Archosauria). Unpublished PhD Dissertation, University of New Mexico, Albuquerque, 404 pp. Hunt, Adrian P. 2001. The vertebrate fauna, biostratigraphy, and biochronology of the type Revueltian land-vertebrate-faunachron, Bull Canyon Formation (Upper Triassic), east central New Mexico. pp. 123-151 in Spencer G. Lucas and Dana Ulmer-Scholle (eds.), Geology of Llano Estacado, New Mexico Geological Society Guidebook 52.

Hunt, Adrian P., Spencer G. Lucas, Andrew B. Heckert, Robert M. Sullivan and Martin G. Lockley. 1998. Late Triassic dinosaurs from the western United States. Geobios 31:511-531.

Irmis, Randall B., William G. Parker, Sterling J. Nesbitt, and Jun Liu. 2007. Early ornithischian dinosaurs: the Triassic record. Historical Biology 19(1):3-22.

Long, R. A. & P. A. Murry, 1995. Late Triassic (Carnian and Norian) Tetrapods from the Southwestern United States. New Mexico Museum of Natural History & Science. Bull. 4. 254 pp.

Nesbitt, Sterling J., Randall B. Irmis, and William G. Parker. 2007. A critical reevaluation of the Late Triassic dinosaur taxa of North America. Journal of Systematic Palaeontology 5(2):209-243.

Parker, William G., Randall B. Irmis, Stirling J. Nesbitt, Jeffrey W. Martz and Lori S. Browne. 2005. The Late Triassic pseudosuchian Revueltosaurus callenderi and its implications for the diversity of early ornithischian dinosaurs. Proceedings of the Royal Society, Series B 272:963-969.

J. A. Spielmann, S. G. Lucas, L. F. Rinehart, A. P. Hunt, A. B. Heckert and R. M. Sullivan. 2007. Oldest records of the Late Triassic theropod dinosaur Coelophysis bauri. In S. G. Lucas & J. A. Spielmann (eds.), The Global Triassic. New Mexico Museum of Natural History and Science Bulletin 41:384-401 —Preceding unsigned comment added by 68.4.61.237 (talk) 18:29, 21 December 2008 (UTC)


 * Wow, that's a lot of info. You're very knowledgeable, but I have the feeling you're an "insider" on the issue, am I right? Anyway, I'll look into making any needed changes to the fauna sections sometime soon, probably tomorrow. Thank you for taking the time to help us hear at Wiki. :)


 * Ornithischians: What about Weishampel et al's "undescribed" genus? Is that an indeterminate archosauriforme? Undescribed new genus of archosauriforme? What about the tracks attributed to ornithischians?


 * Eucoelophysis: But the genus is still valid, right?


 * Coelophysis spp: Ok, they're valid, but Weishampel et al describes Chinle remains that had been attributed to them as being indeterminate ceratosaurian. Are the Chinle C. species really indeterminate or has their recognizable presence been verified?


 * Herrerasaurids: Are the remains you referred to still considered Chindesaurus? For the Cooper Canyon remains, it sounds like you meant multiple indeterminate saurischians, an indeterminate theropod and a shuvosaurid? I'm a tad confused, the chart in the article based on Weishampel et al doesn't have either Chindesaurus or any indeterminate herrerasaurids in the Cooper Canyon. Chindesaurus is listed as being in the Petrified Forest and maybe Bull Canyon. Indet. Herrerasaurids are listed only under bull canyon.


 * Abyssal (talk) 02:57, 22 December 2008 (UTC)

Updates to Weishampel et. al.
Here are the updates to Weishampel et. al.

CHINLE FORMATION/PETRIFIED FOREST FORMATION (ARIZONA):

1. "Coelophysis bauri" as listed for Arizona is now Coelophysis sp. (Nesbitt et. al., 2007) 2. Prosauropoda indet. (=?Anchisauridae indet.) is based on a proximal femur (UCMP 139487) that Hunt et. al. (1998) reidentify as non-dinosaurian. There are thus no confirmed body fossils of prosauropods from the Late Triassic of North America. 3. Revueltosaurus callenderi is a valid taxon of pseudosuchian(Parker et. al., 2005).

CHINLE FORMATION/BLUEWATER CREEK FORMATION (ARIZONA):

1. Tecovasaurus murryi has been relegated to Archosauriformes incertae sedis, but remains a valid genus (Irmis et. al., 2007)

CHINLE FORMATION/SANTA ROSA FORMATION (NEW MEXICO):

1. Theropoda indet. is based on NMMNH P-13006, NMMMNH P-25749, and NMMNH P-25790, now Archosauria indet. (Nesbitt et. al., 2007)

2. Undescribed ornithischian is now Krzyzanowskisaurus Heckert, 2005

CHINLE FORMATION/GARITA CREEK FORMATION (NEW MEXICO):

1. Theropoda indet. is based on indeterminate pes and caudal centra reported by Hunt et. al. (1998).

CHINLE FORMATION/BLUEWATER CREEK FORMATION (NEW MEXICO):

1. Theropoda indet. is based on two specimens (NMMNH P-18400, NMMNH P-18401)(=Cinizasaurus hunti Heckert, 1997), now Archosauriformes indet. (Nesbitt et. al., 2007).

2. Tecovasaurus murryi is a valid taxon assignable to Archosauriformes incertae sedis.(Irmis et. al., 2007).

3. "Ornithischian tracks" are indistinguishable from Grallator tracks (see Nesbitt et. al., 2007)

Eucoelophysis baldwini remains a valid genus, but is not a coelophysoid theropod (Ezcurra, 2006; Nesbitt et. al., 2007). Therefore, there is no justification for considering Eucooelophysis invalid, 'contra' Weishampel et. al.

Hunt and Lucas (1991) failed to go far enough in their paper to determine the taxonomic status of specimens referred to Coelophysis, despite considering C. bauri, C. longicollis, and C. willistoni to be 'nomina dubia'. A re-description of these taxa is needed to determine their systematic position.

Under Bull Canyon Formation, "Herrerasauridae indet." is based on NMMNH P-4569 (=Comanchesaurus kuesi Hunt, 1994), while "Ceratosauria indet." refers to NMMNH P-17375 (=Cryptoraptor lockleyi Hunt, 1994). The faunal list under Cooper canyon formation remains the same.

Ezcurra, M.D., 2006. A review of the systematic position of the dinosauriform archosaur Eucoelophysis baldwini Sullivan & Lucas, 1999 from the Upper Triassic of New Mexico, USA. Geodiversitas, 28(4):649-684.

Hunt, Adrian P. 1994. Vertebrate paleontology and biostratigraphy of the Bull Canyon Formation (Chinle Group, Upper Triassic), east-central New Mexico with revisions of the families Metoposauridae (Amphibia: Temnospondyli) and Parasuchidae (Reptilia:Archosauria). Unpublished PhD Dissertation, University of New Mexico, Albuquerque, 404 pp.

Hunt, Adrian P. 2001. The vertebrate fauna, biostratigraphy, and biochronology of the type Revueltian land-vertebrate-faunachron, Bull Canyon Formation (Upper Triassic), east central New Mexico. pp. 123-151 in Spencer G. Lucas and Dana Ulmer-Scholle (eds.), Geology of Llano Estacado, New Mexico Geological Society Guidebook 52.

Hunt, A.P. and Lucas, S.G., 1991. Rioarribasaurus, a new name for a Late Triassic dinosaur from New Mexico (USA). Paläontologische Zeitschrift 65 (1/2), 191-198.

Hunt, Adrian P., Spencer G. Lucas, Andrew B. Heckert, Robert M. Sullivan and Martin G. Lockley. 1998. Late Triassic dinosaurs from the western United States. Geobios 31:511-531.

Irmis, Randall B., William G. Parker, Sterling J. Nesbitt, and Jun Liu. 2007. Early ornithischian dinosaurs: the Triassic record. Historical Biology 19(1):3-22.

Long, R. A. & P. A. Murry, 1995. Late Triassic (Carnian and Norian) Tetrapods from the Southwestern United States. New Mexico Museum of Natural History & Science. Bull. 4. 254 pp.

Nesbitt, Sterling J., Randall B. Irmis, and William G. Parker. 2007. A critical reevaluation of the Late Triassic dinosaur taxa of North America. Journal of Systematic Palaeontology 5(2):209-243.

Parker, William G., Randall B. Irmis, Stirling J. Nesbitt, Jeffrey W. Martz and Lori S. Browne. 2005. The Late Triassic pseudosuchian Revueltosaurus callenderi and its implications for the diversity of early ornithischian dinosaurs. Proceedings of the Royal Society, Series B 272:963-969. —Preceding unsigned comment added by 68.4.61.237 (talk) 02:19, 23 December 2008 (UTC)

Chinle VS Docum
Chinle VS Docum

At present there is an argument about the name of this stratigraphic unit. Should it be Docum - first used in 1890, or Chinle - first used in 1917. Docum is favored by Texas geologists, Chinle by Arizona and New Mexico geologists.

An underlying question is: "was it a single event or two events"?

To my mind, the widely held view that the trees lived and died peacefully of old age in an environment of gently rolling hills and gentle streams does not match the evidence.

1. Where are the tree limbs and root balls? 2. Why is the area so widespread? It covers an area roughly a thousand miles long by 300-500 miles wide, = ~200,000 to 400,000 square miles!

An examination of the layers reveals there was a repeating wide spread phenomenon involved over time. The ~250 Million year old bottom layer of the Chinle Formation is called the Shinarump, containing petrified trees over a vast area.

Publication: Gilbert, G.K., 1875, Report upon the geology of portions of Nevada, Utah, California, and Arizona, Chapter 6, IN Report on the geographical and geological explorations and surveys west of the One Hundredth Meridian (Wheeler): U.S. Geological and Geographical Survey, Publication of the Wheeler Survey, v. 3, p. 17-187. Summary: "First used as a name applied to a 50-ft thick yellow conglomerate with petrified wood above 200 ft of chocolate sandstone and shale [Moenkopi Formation] and below variegated gypsiferous clay [Chinle Formation]. Source of name not stated. [Shinarump cliffs and Shinarump mesa which are in southern Kane Co, UT in the Plateau sedimentary province, noted on p. 84.] No type locality designated. Section measured at north fork of Virgin River from vicinity of Mountain Lakelet to Rockville, Washington Co, UT. Shinarump also identified by E. E. Powell, Chapter 8, p. 247-248, 270-273, 284, in Washington Co, UT at Pine Valley Mountains, near Paria, near Toquerville, and in NV in the Virgin Range in the Great Basin province. Assigned to the Trias. Source: GNU records (USGS DDS-6; Denver GNULEX).

The lowermost member of the Chinle, the Shinarump, consists of a white, gray, and brown conglomerate made of coarse sandstone, and thin lenses of sandy mudstone, along with plentiful petrified wood. The Shinarump was laid down in braided streams that flowed through valleys eroded into the underlying Moenkopi Formation.[8] This member of the Chinle forms prominent cliffs with thickness up to 200 feet (60 m), and its name comes from a Native American word meaning "wolf's rump" (a reference to the way this member erodes into gray, rounded hills)"

The "Shinarump Valley" now under the Chinle, covered existing Nevada, Utah, the southwestern corner of Colorado, Arizona, New Mexico, and possibly the panhandle of Texas.

What happened to create this vast area of trees that knocked them down, buried them, and then allowed them to petrify?

This event was followed by Offshore volcanoes where California would eventually be born were constantly showering the western area with ash-fall after ash-fall, laying down thick ash layers now known as the Painted Desert - fertile Chinle soil where big trees could grow again.

About 225 Million years ago something unusual happened again in the area now known as the southwestern United States to produce the vast area known as the Petrified Forest Member of the Chinle (AKA "The Painted Desert") Formation and Dockum Formation as it was named in Texas. It is inter-continental, stretching from Nevada (the west coast back then) to western Texas. That is an area roughly 1,000 miles long by 500 miles wide covering ~200,000 to ~500,000 Square miles!

Remnants of that whole area are covered with 225 million year old petrified wood. What happened (again!!!) to cause that?

A firsthand report from 1890 -Cummins, W.F., 1890, The Permian of Texas and its overlying beds

states:"A few miles before reaching Dockum, situated in the western edge of Dickens County, I came upon a bed of conglomerate sandstone* and red clay, resting unconformably upon the clays and sandstones of the upper Permian, entirely unlike anything I have heretofore seen in Texas. This formation lies along the foot of the Staked Plains in a narrow belt. Because of its extensive occurrence in the vicinity of Dockum, I gave the formation the name of Dockum Beds, but will not for the present attempt to determine their correlation. I have found everywhere on the beds of the Permian belt pieces of conglomerate and large pebbles of white quartz that did not belong to the Trinity sands of the Cretaceous which were supposed to overlie the Permian to the westward, and it is a matter of interest to know where this drift came from. The fragments of conglomerate increased in size as we traveled westward until we came upon the beds of that material in the vicinity of Dockum, and the question was solved as to the origin of the fragments of conglomerate and the quartz pebbles. In the conglomerate are many silicified trunks of trees, some of them of great length. In the red clay above the conglomerate are fossil remains of large reptiles, whose species I was unable to determine in the field. In the upper sandstone were many casts of a Ohio that I have provisionally called Onto documensis. In most places that fossil occurs only as casts, and in one place only did I find specimens of both valves, and they were so badly incrusted with carbonate of lime that the peculiar markings of the shell could not be seen. The sandstone was everywhere full of scales of mica, some of the scales being one-sixteenth of an inch square. The whole thickness of this formation in this vicinity is about 150 feet. These beds extend under the Staked Plains. I traced them up Blanco Canyon to the falls of White River, where they pass out of sight under the beds of the overlying strata. There are a great many springs of clear pure water flowing from these beds, and wherever the formation has been penetrated by wells, an abundance of good water has been obtained."

Re-Quote: "I have found everywhere on the beds of the Permian belt pieces of conglomerate and large pebbles of white quartz that did not belong to the Trinity sands of the Cretaceous which were supposed to overlie the Permian to the westward, and it is a matter of interest to know where this drift came from. The fragments of conglomerate increased in size as we traveled westward until we came upon the beds of that material in the vicinity of Dockum . . . many silicified trunks of trees, some of them of great length."

What was the home source of the conglomerate and white quartz found scattered across central Texas? Note that the conglomerate got finer and smaller the further east it went! It had to have come from an area northwest of Dockum. Where? What force scattered it?

A that time the Atlantic ocean was opening up, shoving North America westward.

My conclusion: There appears to be TWO layers of Petrified Wood in the Petrified Forest Member with a sand stone layer between them.

I suspect repeating collapses of the highly pressured western sea-floor generated huge tsunamis that repeatedly rushed southeast, ripping up the trees, then burying them as the waters retreated.

As for the name. . . For me, the evidence is conclusive that Chinle and Docum are the result of a single event and should only have one name. Which?

Chinle has class, mystery, pizazz. Docum? Not so much. Nevada, Utah, Arizona, New Mexico against a tiny portion of Texas? No contest. Should first use hold sway? Not if it is in poor taste.

DaveC1 (talk) 19:31, 12 August 2017 (UTC)


 * There are two significant concerns here. First, your discussion consists mainly of original research, which is not allowed in Wikipedia articles as discussed in No original research. If you want to make changes to the article to include your ideas, any changes must be backed up by reliable sources. Finally, there have been innumerable detailed investigations of the sediments, paleoenvironments, and paleosols of Chinle Formation. These results of these studies have been published in and reviewed by innumerable reliable sources since 1875 and 1890. The overwhelming conclusion is that the Chinle Fomation consists mainly fluvial and lacustrine sediments that contain numerous paleosols multiple periods of fluvial aggradation. Any changes need to based upon a consideration of such publications (reliable sources) and not original research based on antiquated sources.


 * Some of the many, many papers to read:


 * Blakey, Ronald C., and Richard Gubitosa.1983, Late Triassic paleogeography and depositional history of the Chinle Formation, southern Utah and northern Arizona, in Reynolds, M.W., and Dolly, E.D., eds., Mesozoic Paleogeography of the West-Central United States, Society of Economic Paleontologists and Mineralogists, Rocky Mountain Section, Rocky Mountain Paleogeography Symposium 2, p. 57–76.


 * Driese, S., L. Nordt, S. Atchley, S. Dworkin, D. Peppe, and C. Monger, 2010, Paleosols and Soil Surface System Analogs. SEPM-NSF Research Conference and Workshop, Petrified Forest National Park, Arizona, Date: Sept. 21-26, 2010, USA. Baylor University


 * Dubiel, R.F. and Hasiotis, S.T., 2011. Deposystems, paleosols, and climatic variability in a continental system: The Upper Triassic Chinle Formation, Colorado Plateau, USA. From river to rock record: the preservation of fluvial sediments and their subsequent interpretation. SEPM Special Publication, 97, pp.393-421.


 * Lehman, T. and Chatterjee, S., 2005. Depositional setting and vertebrate biostratigraphy of the Triassic Dockum Group of Texas. Journal of Earth System Science, 114(3), pp.325-351.


 * Loughney, K.M., Fastovsky, D.E. and Parker, W.G., 2011. Vertebrate fossil preservation in blue paleosols from the Petrified Forest National Park, Arizona, with implications for vertebrate biostratigraphy in the Chinle Formation. Palaios, 26(11), pp.700-719. Paul H. (talk) 02:11, 13 August 2017 (UTC)