Wahweap Formation

Wahweap Formation
Stratigraphic range: Campanian, 82.2–77.3 Ma
↓
Wahweap Formation, Grand Staircase–Escalante National Monument, Utah
TypeGeological formation
Unit ofKaiparowits Plateau
Sub-unitsLast Chance Creek Member, Reynolds Point Member, Coyote Point Member, Pardner Canyon Member
UnderliesKaiparowits Formation
OverliesStraight Cliffs Formation
Lithology
Primarysandstone
Location
Coordinates37°30′N 111°42′W / 37.5°N 111.7°W / 37.5; -111.7
RegionNorth America
Country USA
ExtentSouthern Utah, Northern Arizona
Type section
Named forWahweap Creek

The Wahweap Formation of the Grand Staircase–Escalante National Monument is a geological formation in southern Utah and northern Arizona, around the Lake Powell region, whose strata date back to the Late Cretaceous (Campanian stage). Dinosaur remains are among the fossils that have been recovered from the formation.[1]

Age

The Wahweap formation is divided into four members, which are listed below with their respective ages:[2]

  • Last Chance Creek Member: 82.17-81.55 Ma
  • Reynolds Point Member: 81.55-80.61 Ma
  • Coyote Point Member: 80.61-79 Ma
  • Pardner Canyon Member: 79-77.29 Ma

Paleobiota

Invertebrates

The Wahweap Formation shows a substantial amount of invertebrate activity ranging from fossilized insect burrows in petrified logs[3] to various mollusks that characterize the shell beds. Large fossilized crabs are common at most shell bed sites in the Wahweap,[4] and over 1,900 gastropod specimens (of four likely genera) have been unearthed in the formation's siltstone.[5]

Elasmobranchs

Elasmobranchs of the Wahweap Formation
Taxon Species Locality Member Material Notes Images
Cantioscyllium[6] C. estesi
  • MNA Locality 705
  • MNA Locality 455-1
  • UMNH VP Locality 82
 MNA V10230-32, MNA V10384-85, MNA 10390, UMNH VP 18915-16, UMNH VP 18919; teeth A nurse shark which inhabited freshwater.
Chiloscyllium griseum (grey bamboo shark)
Hybodus hauffianus
Chiloscyllium[6] C. missouriense
  • UMNH VP Locality 77
  • MNA Locality 455-1
 MNA V10386, UMNH VP 18880, UMNH VP 18882, UMMNH VP 18886, UMNH VP 18887, UMNH VP 18888; teeth A bamboo shark which inhabited freshwater. One specimen is similar to Restesia americana.
Columbusia[6] C. deblieuxi UMNH VP Locality 77 UMNH VP 18877, UMNH VP 18879, UMNH VP 18836, UMNH VP 18876, UMNH VP 18878; teeth A sclerorhynchid ray, closely related to Squatirhina.
Cristomylus[6] C. ciffelli
  • MNA Locality 456-1
  • UMNH VP Locality 77
  • UMNH VP Locality 82
  • MNA V9531, MNA V9568, MNA V9600, UMNH VP 17393; symphysial teeth
  • MNA V9502, MNA V9525, MNA V9569, MNA V9633, MNA V9635, MNA V9652, UMNH VP 17393, UMNH VP 17395, UMNH VP 17399, UMNH VP 17404; small teeth
  • MNA V9593, MNA V9683, MNA V9686, UMNH VP 17401; large teeth
 A small guitarfish, suited for handling hard-shelled prey.
Hybodus?[6][7] H. sp MNA Locality 456-2 MNA V10387; Tooth A large hybodont shark reaching over 2 m (6.6 ft) in length. Normally a marine species but would enter freshwater environments
Lonchidion[6] L. sp. UMNH VP Locality 82 UMNH VP 18917; Tooth Smaller than Lonchidon selachos.
Texatrygon[6] T. brycensis
  • UMNH VP Locality 77
  • UMNH VP Locality 82
  • UMNH VP 18882-83; Rostral teeth
  • UMNH VP 18836, UMNH VP 18885, UMNH VP 18889-94, UMNH VP 18920; Oral teeth
  • UMNH VP 18918; denticle
 A sawfish.

Osteichthyes

Osteichthyes of the Wahweap Formation
Taxon Genus Locality Member Material Notes Images
Lepidotes[8] Indeterminate Teeth A seminotiform fish, no extant relatives live today.
Albula vulpes (Bonefish)
Micropycnodon M. sp. MNA Locality 706-2 MNA V10336; pharyngeal tooth A pycnodontiform fish, adapted to crush its prey.
Paralbula P. sp. Teeth A bonefish which is adapted to eating hard-shelled prey.
Polyodontidae[8] Indeterminate MNA Locality 456-2 MNA 10356; denticle A paddlefish, very rare in the Wahweap Formation.

Salamanders

Lissamphibians of the Wahweap Formation
Taxon Species Locality Member Material Notes Images
Gen. nov.[9] sp. nov. UMNH VP Locality 77 UMNH VP 19209; trunk vertebra Higher level relationships are uncertain. Similar to sirenids, but lacks sirenid synapomorphies.
Opisthotriton[9] O. sp. UMNH VP Locality 130
  • UMNH VP 19194-19198; atlantes
  • UMNH VP 19199-19200; trunk vertebrae
 A batrachosauroidid, a family of extinct aquatic salamanders.
Scapherpeton[9] S. sp. UMNH VP Locality 77 UMNH VP 19186; atlas A scapherpetontid.

Dinosaurs

Dinosaurs known from the Wahweap include at least 2 species of hadrosaur, at least two ceratopsians[10] and at least one theropod.[11]

Dinosaurs of the Wahweap Formation
Taxon Species Locality Member Material Notes Images

Acristavus[12]

A. gagslarsoni

"near the junction of Smokey Mountain Road and Right Hand Collet Canyon" Upper part of Reynolds Point Member UMNH VP 16607; "a partial articulated skull roof including lacrimals and entire braincase, and a single cervical vertebra"

A hadrosaurid closely related to Brachylophosaurus and Maiasaura. Also known from the Two Medicine Formation.

Acristavus
Adelolophus
Brachylophosaurus
Diabloceratops
Lythronax
Lythronax
Machairoceratops

Adelolophus[13]

A. hutchisoni

UCMP V98173[14] Lower part of Coyote Point Member

UCMP 152028; partial maxilla

A lambeosaurine hadrosaurid, possibly a parasaurolophin.

Ankylosauridae[15] Indeterminate Coyote Point Member OMNH 21280 (in part), OMNH 21858, OMNH 24276; Teeth
Brachylophosaurus[16] Indeterminate Death Ridge Upper part of Coyote Point Member UMNH VP 9548; "Partial limb bones and a partial maxilla" Different from Acristavus.
Centrosaurinae[17] Indeterminate Nipple Butte Upper part of Last Chance Creek Member UMNH VP 16704; Partial skull Originally referred to Diabloceratops, but is more derived, possibly a nasutoceratopsin.
Centrosaurinae[17] Indeterminate Pilot Knoll Upper part of Last Chance Creek Member UMNH VP 20600; "A partial braincase and a nearly complete parietosquamosal frill" Also known as "Wahweap Centrosaurine A." Similar to Albertaceratops.
Centrosaurinae[17] Indeterminate Death Ridge Upper part of Coyote Point Member UMNH VP 9549; "Partial frill and some postcranial elements" Also known as "Wahweap Centrosaurine C." Possibly has spikes similar to Styracosaurus.

Diabloceratops[18]

D. eatoni

42Ka800V, south side of Last Chance Canyon Middle part of Reynolds Point Member

UMNH VP 166999; "a skull preserving the entire left side of the skull and portions of the right side"

The older specimen from Nipple Butte may not belong to Diabloceratops.

Lythronax[19]

L. argestes

UMNH VP Locality 1501 Lower part of Reynolds Point Member UMNH VP 20200; partial skeleton

A tyrannosaurine

Machairoceratops[20]

M. cronusi

Star Seep Coyote Point Member

UMNH VP 20550; partial skull

A centrosaurine closely related to Diabloceratops. Previously known as "Wahweap Centrosaurine B."
Nodosauridae[15] Indeterminate
  • Last Chance Creek Member?
  • Reynolds Point Member
  • Coyote Point Member
  • OMNH 21280 (in part), OMNH 21992, OMNH 24278; Teeth
  • UMNH VP 13981, UMNH VP 15664, UMNH VP 16408, UMNH VP 21207; osteoderms
  • a cranium (lost)
  • a partial skeleton
 The skeleton was under excavation as of 2013. The cranium was only tentatively identified as a nodosaurid, but now can't be confirmed.
Pachycephalosauridae[21] Indeterminate Clints Cove Lower part of Reynolds Point Member
  • UMNH VP 11939; incomplete frontoparietal dome
  • some isolated teeth
 The dome doesn't preserve diagnostic features, so its affinity with other pachycephalosaurids is uncertain.
Saurolophinae[13] Indeterminate Reynolds Point Member
  • UMNH VP 21087; partial juvenile skeleton
  • UMNH VP 13881; partial adult skeleton
 Probably represents a new distinct taxon.

Mammals

A maniraptoran dinosaur digging a primitive mammal out of its burrow, as per the 2010 discovery by Simpson et al. of trace fossils indicating a predator–prey relationship in the Wahweap Formation.[22]

A fair number of mammals spanning the lower Campanian are known from the Wahweap as well, including at least 15 genera of multituberculates, cladotherians, marsupials, and placental insectivores.[23]

Trace fossils

Trace fossils are also relatively abundant in the Wahweap, and include vertebrate tracks as well as burrow activity. Tracks preserved in the capping sandstone indicate the presence of crocodylomorphs, which had been previously known in this area only from teeth elements, as well as ornithischian dinosaurs. At least one possible theropod track has been identified in this area as well.[24]

In 2010 a unique trace fossil from the Wahweap was discovered that indicates a predator–prey relationship between dinosaurs and primitive mammals. The trace fossil includes at least two fossilized mammalian den complexes as well as associated digging grooves presumably caused by a maniraptoran dinosaur. The proximity indicates a case of probable active predation of the burrow inhabitants by the owners of the claw marks.[22]

See also

References

  1. ^ Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Cretaceous, North America)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 574–588. ISBN 0-520-24209-2.
  2. ^ Beveridge, Tegan L.; Roberts, Eric M.; Ramezani, Jahandar; Titus, Alan L.; Eaton, Jeffrey G.; Irmis, Randall B.; Sertich, Joseph J. W. (April 1, 2022). "Refined geochronology and revised stratigraphic nomenclature of the Upper Cretaceous Wahweap Formation, Utah, U.S.A. and the age of early Campanian vertebrates from southern Laramidia". Palaeogeography, Palaeoclimatology, Palaeoecology. 591: 110876. Bibcode:2022PPP...59110876B. doi:10.1016/j.palaeo.2022.110876. ISSN 0031-0182.
  3. ^ De Blieux, Donald D. "Analysis of Jim's hadrosaur site; a dinosaur site in the middle Campanian (Cretaceous) Wahweap Formation of Grand Staircase–Escalante National Monument (GSENM), southern Utah." Abstracts with Programs – Geological Society of America, vol. 39, no. 5, pp.6, May 2007
  4. ^ Kirkland, James Ian. "An inventory of paleontological resources in the lower Wahweap Formation (lower Campanian), southern Kaiparowits Plateau, Grand Staircase–Escalante National Monument, Utah." Abstracts with Programs – Geological Society of America, vol.37, no.7, pp.114, Oct 2005.
  5. ^ Williams, Jessica A J; Lohrengel, C Frederick. Preliminary study of freshwater gastropods in the Wahweap Formation, Bryce Canyon National Park, Utah. Abstracts with Programs – Geological Society of America, vol. 39, no. 5, pp.43, May 2007
  6. ^ a b c d e f g Kirkland, James I.; Eaton, Jeffrey G.; Brinkman, Donald B. (2013). "Elasmobranchs from Upper Cretaceous Freshwater Facies in Southern Utah". In Titus, Alan L.; Loewen, Mark A. (eds.). At the Top of the Grand Staircase: The Late Cretaceous of Southern Utah. Bloomington: Indiana University Press. pp. 153–194. ISBN 9780253008961.
  7. ^ Maisch, Michael W.; Matzke, Andreas T. (June 1, 2016). "A new hybodontid shark (Chondrichthyes, Hybodontiformes) from the Lower Jurassic Posidonienschiefer Formation of Dotternhausen, SW Germany". Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen. 280 (3): 241–257. doi:10.1127/njgpa/2016/0577. ISSN 0077-7749.
  8. ^ a b Brinkman, Donald B.; Newbrey, Michael G.; Neuman, Andrew G.; Eaton, Jeffrey G. (2013). "Freshwater Osteichthyes from the Cenomanian to Late Campanian of Grand Staircase–Escalante National Monument, Utah". In Titus, Alan L.; Loewen, Mark A. (eds.). At the Top of the Grand Staircase: The Late Cretaceous of Southern Utah. Bloomington: Indiana University Press. pp. 195–236. ISBN 9780253008961.
  9. ^ a b c Gardner, James D.; Eaton, Jeffrey G.; Cifelli, Richard L. (2013). "Preliminary Report on Salamanders (Lissamphibia; Caudata) from the Late Cretaceous (Late Cenomanian–Late Campanian) of Southern Utah, U.S.A.". In Titus, Alan L.; Loewen, Mark A. (eds.). At the Top of the Grand Staircase: The Late Cretaceous of Southern Utah. Bloomington: Indiana University Press. pp. 237–272. ISBN 9780253008961.
  10. ^ "New Horned Dinosaurs from the Wahweap Formation" (PDF). Utah Geological Survey. 2007. Archived from the original (PDF) on August 31, 2021.
  11. ^ John Wesley Powell Memorial Museum display, visited April 30, 2009
  12. ^ Gates, T.A.; Horner, J.R.; Hanna, R.R.; Nelson, C.R. (2011). "New unadorned hadrosaurine hadrosaurid (Dinosauria, Ornithopoda) from the Campanian of North America". Journal of Vertebrate Paleontology. 31 (4): 798–811. Bibcode:2011JVPal..31..798G. doi:10.1080/02724634.2011.577854. S2CID 8878474.
  13. ^ a b Gates, Terry A.; Jinnah, Zubair; Levitt, Carolyn; Getty, Michael A. (2014). "New Hadrosaurid (Dinosauria, Ornithopoda) Specimens from the Lower—Middle Campanian Wahweap Formation of Southern Utah". In Eberth, David A.; Evans, David Christopher; Ralrick, Patricia E. (eds.). Hadrosaurs. Indiana University Press. pp. 156–173. ISBN 9780253013859.
  14. ^ Holroyd, Patricia A.; Hutchison, J. Howard (June 9, 2016). "Fauna and setting of the Adelolophus hutchisoni type locality in the Upper Cretaceous (Campanian) Wahweap Formation of Utah" (PDF). PaleoBios. 33. doi:10.5070/P9331031196. ISSN 0031-0298.
  15. ^ a b Loewen, Mark A.; Burns, Michael E.; Getty, Michael E.; Kirkland, James I.; Matthew K., Vickaryous (2013). "Review of Late Cretaceous Ankylosaurian Dinosaurs from the Grand Staircase Region, Southern Utah". In Titus, Alan L.; Loewen, Mark A. (eds.). At the Top of the Grand Staircase-The Late Cretaceous of Southern Utah. Bloomington: Indiana University Press. pp. 445–462. ISBN 9780253008961.
  16. ^ Gates, Terry A.; Lund, Eric K.; Boyd, C.A.; DeBlieux, Donald D.; Titus, Alan L.; Evans, David C.; Getty, Michael A.; Kirkland, James I.; Eaton, Jeffrey J. (2013). "Ornithopod Dinosaurs from the Grand Staircase–Escalante National Monument Region, Utah, and Their Role in Paleobiogeographic and Macroevolutionary Studies". In Titus, Alan L.; Loewen, Mark A. (eds.). At the Top of the Grand Staircase: The Late Cretaceous of Southern Utah. Bloomington: Indiana University Press. pp. 463–481. ISBN 9780253008961.
  17. ^ a b c Loewen, Mark A.; Farke, Andrew A.; Sampson, Scott D.; Getty, Michael A.; Lund, Eric K.; O'Connor, Patrick M. (2013). "Ceratopsid Dinosaurs from the Grand Staircase of Southern Utah". In Titus, Alan L.; Loewen, Mark A. (eds.). At the Top of the Grand Staircase: The Late Cretaceous of Southern Utah. Bloomington: Indiana University Press. pp. 488–503. ISBN 9780253008961.
  18. ^ Kirkland, James I.; Deblieux, Donald D. (2010). "New basal centrosaurine ceratopsian skulls from the Wahweap Formation (Middle Campanian), Grand Staircase–Escalante National Monument, southern Utah" (PDF). In Ryan, M.J.; Chinnery-Allgeier, B.J.; Eberth, D.A. (eds.). New Perspectives on Horned Dinosaurs: The Royal Tyrell Museum Ceratopsian Symposium. Bloomington: Indiana University Press. pp. 117–140. ISBN 9780253007797.
  19. ^ Loewen, Mark A.; Irmis, Randall B.; Sertich, Joseph J. W.; Currie, Philip J.; Sampson, Scott D. (November 6, 2013). "Tyrant Dinosaur Evolution Tracks the Rise and Fall of Late Cretaceous Oceans". PLOS ONE. 8 (11): e79420. Bibcode:2013PLoSO...879420L. doi:10.1371/journal.pone.0079420. ISSN 1932-6203. PMC 3819173. PMID 24223179.
  20. ^ Lund, Eric K.; O’Connor, Patrick M.; Loewen, Mark A.; Jinnah, Zubair A. (May 18, 2016). "A New Centrosaurine Ceratopsid, Machairoceratops cronusi gen et sp. nov., from the Upper Sand Member of the Wahweap Formation (Middle Campanian), Southern Utah". PLOS ONE. 11 (5): e0154403. Bibcode:2016PLoSO..1154403L. doi:10.1371/journal.pone.0154403. ISSN 1932-6203. PMC 4871575. PMID 27192148.
  21. ^ Evans, David C.; Williamson, Thomas; Loewen, Mark A.; Kirkland, James I. (2013). "Review of Pachycephalosaurian Dinosaurs from Grand Staircase–Escalante National Monument, Southern Utah". In Titus, Alan L.; Loewen, Mark A. (eds.). At the Top of the Grand Staircase: The Late Cretaceous of Southern Utah. Bloomington: Indiana University Press. pp. 482–487. ISBN 9780253008961.
  22. ^ a b Simpson, Edward L.; Hilbert-Wolf, Hannah L.; Wizevich, Michael C.; Tindall, Sarah E.; Fasinski, Ben R.; Storm, Lauren P.; Needle, Mattathias D. (2010). "Predatory digging behavior by dinosaurs". Geology. 38 (8): 699–702. Bibcode:2010Geo....38..699S. doi:10.1130/G31019.1.
  23. ^ Eaton, Jeffrey G; Cifelli, Richard L. "Review of Cretaceous mammalian paleontology; Grand Staircase–Escalante National Monument, Utah." Abstracts with Programs – Geological Society of America, vol.37, no.7, pp.115, Oct 2005
  24. ^ Tester, Edward et al. Isolated vertebrate tracks from the Upper Cretaceous capping sandstone member of the Wahweap Formation; Grand Staircase–Escalante National Monument, Utah Abstracts with Programs – Geological Society of America, vol. 39, no. 5, pp.42, May 2007