Pierre Shale

The Pierre Shale is a geologic formation or series in the Upper Cretaceous. It can be found east of the Rocky Mountains in the Great Plains, from Pembina Valley in Canada to New Mexico.

The Pierre Shale was described by Meek and Hayden in 1862. They said it is a dark-gray shale with veins and seams of gypsum, and concretions of iron oxide. The Pierre Shale is about 3,138 feet (956m) thick at the type locality. It lies on top of the Niobrara division and below the Fox Hills beds. It was named for a place near Fort Pierre on the Missouri River in South Dakota.

The Pierre Shale came from the ocean and was laid down in the Western Interior Seaway. It matches other ocean shales farther west, such as the Bearpaw Shale, Mancos Shale and the Lewis Shale. Most of it was laid down in the Campanian Age of the late Cretaceous. Fossils of Baculites baculus found in the upper layers of the Pierre Shale in the Raton, New Mexico area show that it continued to form into the early Maastrichtian.

Mineral resources

The Pierre Shale has important oil in places like the Florence and Cañon City areas in Fremont County, Colorado, and the Boulder Oil Field in Boulder County, Colorado. Recently, natural gas has also been found in the Raton Basin in southern Colorado. Usually, the shale is too hard to get these resources, but in some spots it has cracks that let the oil and gas out.

Paleofauna

Reptiles

Dinosaurs

Mosasaurs

Plesiosaurs

Pterosaurs

Turtles

Fish

Bony fish

Cartilaginous fish

Marine vertebrates

• Gillicus
• Pseudocorax
• Carcharias

Invertebrates

Annelids

Arthropods

Bivalves

Brachiopods

Cephalopods

Echinoderms

Gastropods

Scaphopods

Birds reported from the Pierre Shale Formation
Genus	Species	Location	Stratigraphic position	Material	Images
Brodavis	B. varneri	South Dakota	Sharon Springs Member.
	B. sp.	Manitoba	Pembina Member.
Hesperornis	H. bairdi	South Dakota	Sharon Springs Member.
	H. chowi	Manitoba & South Dakota	Pembina, Millwood, & Sharon Springs Members.
	H. lumgairi	Manitoba	Pembina Member.
	H. macdonaldi	Manitoba & South Dakota.	Gammon, Pembina, Millwood(?), & Sharon Springs Members.
	H. mengeli	Manitoba & South Dakota.	Pembina & Sharon Springs Members.
	H. regalis	Manitoba, South Dakota, & Kansas	Gammon, Pembina, & Sharon Springs Members.
	H. sp.	Manitoba.	Pembina Member.
Hesperornithidae	Gen. et. sp. indeterminate	Manitoba.	Pembina Member.	Multiple isolated synascra.
Hesperornithiformes	Fam., gen. et sp. indet.	Manitoba.	Pembina Member.	Multiple vertebrae, phalanges, tibiotarsal fragments and a fibula.
Ichthyornis	I. sp.	Manitoba.	Pembina Member.	"MDM B77.03.07 (vertebral centrum), B80.05.14 (femur)".

Ornithischians reported from the Pierre Shale Formation
Genus	Species	Location	Material	Images
Claosaurus	C. affinis	South Dakota.	"Pedal phalanx (lost)."

Mosasaurs reported from the Pierre Shale Formation
Genus	Species	Location	Stratigraphic position	Material	Images
Clidastes	C. propython	Manitoba.	Pembina Member.	MDM M74.10.06 (skull, mandible, vertebral column).
		Western Kansas.		Vertebrae associated with 'Plesiosaurus' gulo currently lost.
Globidens	G. dakotensis	South Dakota.	Sharon Springs Member.	FMNH PR 846.
	G. schurmanni	At the Big Bend of the Missouri River, Buffalo County, South Dakota.	Uppermost DeGrey Formation.	"SDSM 74764, partial anterior skeleton, including cranium, jaws, cervical and trunk vertebrae partially articulated, pectoral girdles, partial anterior paddle, isolated humerus and ulna, and isolated caudal vertebrae".
	G. sp.	Northwestern Logan County, Kansas.	Upper level of the Sharon Springs Member.	A nearly complete right dentary (FHSM VP–13828).
Hainosaurus	H. pembinensis	Near Morden, Manitoba.	Pembina Member.
Jormungandr	J. walhallaensis	Cavalier County, North Dakota.	Pembina Member.	Partial skull & skeleton.
Latoplatecarpus	L. nichollsae	"19 km northwest of Morden, Manitoba".	Pembina Member.	A skeleton (CMN 52261).
Mosasauridae	Subfam., gen. et. sp. indeterminate	Manitoba.	Pembina Member.	Fragmentary specimens consisting "mostly of vertebral scraps, ribs and flipper elements".
Mosasaurus	M. conodon	"South Dakota".
	M. missouriensis	"South Dakota".
Platecarpus	P. coryphaeus		Pembina Member.
	P. ictericus		Pembina Member.
	P. somenensis		Pembina Member.
	P. tympaniticus		Pembina Member.	Abundant specimens.
	P. sp.	Manitoba.	Pembina Member.	"Isolated skull elements, humeri and pectoral girdles".
Plioplatecarpinae	Gen. et. sp. indeterminate	Manitoba.	Pembina Member.	Poorly preserved and unprepared remains.
Plioplatecarpus	P. nichollsae	"19 km northwest of Morden, Manitoba".	Pembina Member.	A skeleton (CMN 52261).
Prognathodon	P. overtoni	South Dakota.	Virgin Creek Member.	KUVP 950 (the holotype for the species) and SDSM 3339.
Tylosaurinae	Gen. et. sp. indet.	Manitoba.	Pembina Member.	Isolated limb and girdle elements (MDM M74.28.05, M75.20.06, M82.13.17, M84.09.18).
Tylosaurus	T. pembinensis	Near Morden, Manitoba.	Pembina Member.
	T. proriger	Manitoba.	Pembina Member.	MDM M77.17.07 quadrate, FMNH PR 591 quadrate, pubis, vertebrae.

Plesiosaurs reported from the Pierre Shale Formation
Genus	Species	Location	Stratigraphic position	Material	Images
Alzadasaurus	A. pembertonii	South Dakota.	Sharon Springs Member.	Complete specimen (SDSM 451).
	cf. A. pembertonii	Manitoba.	Pembina Member.	A specimen consisting of two femora, one humerus, two epipodials, fragments of the pelvic girdle and 14 vertebrae (MDM P83.02. 18).
Elasmosauridae	Gen. et. sp. indeterminate	Manitoba.	Pembina Member.
		Logan County, Kansas.	Upper Sharon Springs Member.	KUVP 129744, a specimen associated with 47 gastroliths.
Elasmosaurus	E. platyurus	Kansas.	Sharon Springs member.	Multiple specimens, including the holotype.
	?E. sp.	Manitoba.	Pembina Member.	"An incomplete specimen (TMP P84.162.4), consisting of pelvic girdle, distal end of a propodial, an epipodial and 21 vertebrae".
Martinectes	M. bonneri	Wyoming & South Dakota.	Sharon Springs Member and Pembina Member.	2 specimens: an adult (UNSM 50133) and a juvenile (UNSM 55810), and several others.
Plesiosauria	Fam., gen. et. sp. indeterminate		Pembina Member.	"Specimens consisting mostly of ribs, caudal vertebrae, broken girdle plates and phalanges".
'Plesiosaurus'	'P.' gulo	Western Kansas.		KUVP 1329 (the original specimen consisted of "eleven cervical, thirteen dorsal, and seven or eight other vertebrae" but now only 3 vertebrae remain).
Polycotylidae	Gen. et. sp. indeterminate	Morden area, Manitoba.	Pembina Member.	Many isolated vertebrae and partial skull remains.
Serpentisuchops	S. pfisterae	Wyoming.	Upper half of the upper member.	"Specimen GPM5001".
Styxosaurus	S. snowii	South Dakota.	Sharon Springs Member.	Complete specimen (SDSM 451).
	cf. S. snowii	Manitoba.	Pembina Member.	A specimen consisting of two femora, one humerus, two epipodials, fragments of the pelvic girdle and 14 vertebrae (MDM P83.02. 18).
		Kansas.	Sharon Springs Member.	NJSM 15435.
Trinacromerum	T. bonneri	Wyoming & South Dakota.	Sharon Springs Member and Pembina Member.	2 specimens: an adult (UNSM 50133) and a juvenile (UNSM 55810), and several others.
	T. cf. T. kirki	Manitoba.	Pembina Member.	TMP P84.162.3.
	T. sp.	Manitoba.	Pembina Member.	Many poorly preserved specimens.

Pterosaurs reported from the Pierre Shale Formation
Genus	Species	Location	Stratigraphic position	Material	Images
Pteranodon	P. longiceps	Kansas, Wyoming & South Dakota.	Sharon Springs Member.	A skull and multiple postcranial elements.

Turtles reported from the Pierre Shale Formation
Genus	Species	Location	Stratigraphic position	Material	Images
Archelon	A. ischyros	Along the Cheyenne River in Custer County, South Dakota.
	A. sp.	Colfax County, New Mexico.		3 carapace fragments (NMMNHP-16079 and P-16104).
Protostega	P. sp.	Manitoba.	Pembina Member.	MDM T75.01.06.
Testudines	Fam., gen. et sp. indet.	Manitoba.	Pembina Member.
Toxochelys	T. latiremis	Kansas & Manitoba.	Pembina Member.

Bony fish reported from the Pierre Shale Formation
Genus	Species	Presence	Stratigraphic position	Material	Images
Apsopelix	A. sp. cf. A. anglicus	Hughes County, South Dakota.	Upper DeGrey Formation.	SDSM 77482.
Bananogmius	B. evolutus	Manitoba.	Pembina Member.	An articulated skull (MDM F75.05.06).
	B. sp.	Near Thornhill, Manitoba.	Pembina Member.	Skull and vertebral column (MMMN V82).
Cimolichthys	C. nepaholica	Manitoba.	Pembina Member.
Cylindracanthus		Hyde County, South Dakota.	Verendrye Formation.	A rostral spine (SDSM 30638).
Enchodus	E. gladiolus		Sharon Springs Member.
	E. petrosus	Manitoba.	Pembina Member and Sharon Springs Member.
	E. cf. saevus	Manitoba.	Pembina Member.	FMNH PF 5391 (a dentary, maxilla and palatine).
	E. sp.	Manitoba.	Pembina Member.	2 isolated vertebrae and isolated palatal fangs.
Ichthyodectes	I. ctenodon	Manitoba.	Pembina Member.	Multiple mandibles and some skull and vertebral material.
Ichthyodectidae	Gen. et. sp. indet.	Manitoba.	Pembina Member.	Vertebrae and partial caudal fins.
Pachyrhizodus	P. caninus	Manitoba.	Pembina Member.	A skull and anterior portions of the body (MDM F74.04.06), and a right dentary (FMNH PF 5397).
	P. minimus	Manitoba.	Pembina Member.	FMNH PF 5402.
	P. sp.	Manitoba.	Pembina Member.	2 isolated vertebral centra (MMMN V73 ).
	P. sp. indet.	Hughes County, South Dakota.	DeGrey Formation.	SDSM 77481.
Pentanogmius	P. evolutus	Manitoba.	Pembina Member.	An articulated skull (MDM F75.05.06).
Protosphyraena	P. gladius	Hyde County, South Dakota.	DeGrey Formation.	SDSM 66288 (major portion of pectoral fin).
	P. sp.	Manitoba.	Pembina Member.	A left premaxilla (FMNH PF 5400).
Stratodus	S. apicalis	Manitoba.	Pembina Member.
Teleostei	Order, fam., gen. et. sp. indet.	Manitoba.	Pembina Member.	Mostly vertebrae, but also caudal fins and skulls in some specimens.
Xiphactinus	X. audax	Manitoba and Lyman County, South Dakota.	Pembina Member and middle part of the Sharon Springs Member.

Cartilaginous fish reported from the Pierre Shale Formation
Genus	Species	Presence	Stratigraphic position	Material	Images
Archaeolamna	A. kopingensis	Western Kansas.	Sharon Springs Member.	A partial skeleton with articulated teeth.
Cretalamna	C. appendiculata	Manitoba.	Pembina Member.	Vertebral centra.
Euselachii	Fam., gen. et sp. indet.	Near Thornhill, Manitoba.	Pembina Member.	"Three vertebral centra, 15 mm in diameter".
Squalicorax	S. sp. aff. S. kaupi	Manitoba.	Pembina Member.	"MDM S80.01.14 (2 teeth), FMNH PF 5399 (1 tooth)".

Cephalopods reported from the Pierre Shale Formation
Genus	Species	Location	Stratigraphic position	Material	Images
Baculites	B. baculus	New Mexico.	Upper & uppermost Pierre Shale.
	B. cf. baculus	Bowman County, North Dakota.	Baculites reesidei Range Zone.	1 broken specimen.
	B. compressus	At the Big Bend of the Missouri River, Buffalo County, South Dakota.	Uppermost DeGrey Formation.
	B. cf. B. eliasi	Northeastern New Mexico.
	B. grandis?	Bowman County, North Dakota.		One large, crushed, badly weathered specimen.
	B. reesidei	Bowman County, North Dakota.	Baculites reesidei Zone.	11 broken specimens.
	B. sp.	Bowman County, North Dakota.	Upper Baculites reesidei Zone.	10 broken exfoliated specimens.
	B. sp.	Northeastern New Mexico.
Belemnitella	B. bulbosa		Upper Pierre Shale.
	B.? sp.	Meade County, South Dakota.	Baculites compressus zone.	1 specimen (BHI-7009).
Didymoceras	D. cochleatum	South Dakota & Wyoming.	Gregory & Red Bird Silty members.	Numerous fragments.
	D. nebrascense	"Northwestern New Mexico through northeastern Montana".
	D. sp.	Colfax County, New Mexico.
Enchoteuthis	E. cobbani	Meade & Pennington counties, South Dakota.	Baculites cuneatus Zone & possibly the underlying B. compressus Zone.	2 specimens.
	E. melanae	Niobrara County, Wyoming.	Baculites obtusus zone, Sharon Springs Member.	Multiple specimens.
Eutrephoceras	E. dekayi	Colorado, Bowman County, North Dakota and Colfax County, New Mexico.	Probably from the Baculites reesidei Zone.
	E. montanaensis	Northeastern New Mexico.
Exiteloceras	E. sp.	Bowman County, North Dakota.		One fragmented body chamber.
Hoploscaphites	H. brevis	Bowman County, North Dakota.		"Ten almost complete specimens and many fragments of early whorls".
	H. crassus	Montana & Wyoming.
	H. criptonodosus	Montana, Wyoming, Colorado, and possibly South Dakota.	"Upper part of the Baculites baculus Zone and overlying B. grandis Zone".
	H. macer	Montana, Wyoming & Colorado.	"Upper part of the Baculites baculus Zone and lower part of the overlying B. grandis Zone".
	H. cf. H. nicolleti	Bowman County, North Dakota.		2 specimens.
	H. nodosus	Near Raton, New Mexico.	"30-45 m below the top of the Pierre Shale".
	H. peterseni	Montana & Wyoming.
	H. plenus	Montana, Wyoming & North Dakota.
	H. quadrangularis	Bowman County, North Dakota.	Probably from the Baculites reesidei Zone.	One broken shaft with aperture.
	H. sp.	Bowman County, North Dakota.		One broken specimen.
	H. sp.	Colfax County, New Mexico.
Jeletzkytes	J. nodosus	At the Big Bend of the Missouri River, Buffalo County, South Dakota.	Uppermost DeGrey Formation.
Placenticeras	P. intercalere	Bowman County, North Dakota.		"One decorticated specimen badly fractured by calcite crystal growth".
	P. meeki	Colfax County, New Mexico and Bowman County, North Dakota.	Baculites reesidei Zone.
	P. newberryi	Colfax County, New Mexico.
Ponteixites	P. robustus	Eastern Montana.
Rhaeboceras	R. burkholderi	Dawson County, Montana.	Upper part of the Pierre Shale (Baculites eliasi zone).
	R. cedarense	Dawson County, Montana.	Baculites baculus/grandis zone.
	R. robustus	Eastern Montana.
Scaphites	S. nodosus	Near Raton.	"About 15 m below the top of the Pierre Shale".
Solenoceras	S. sp.	Bowman County, North Dakota.		3 fragmented specimens.
Tusoteuthis	T. cobbani	Meade & Pennington counties, South Dakota.	Baculites cuneatus Zone & possibly the underlying B. compressus Zone.	2 specimens.
	T. longa	South Dakota.	Baculites compressus Zone.
Uluciala	U. rotundata	South Dakota	Baculites compressus/cuneatus Zone	Two lower beaks, represented by digital files of tomography data