Fort Union Formation

Last updated
Fort Union Formation
Stratigraphic range: Maastrichtian-Selandian (Lancian-Clarkforkian)
~66–58  Ma
Impression of 65 million years old partial fossil leaf of Beringiaphyllum cupanoides and fragments of Sparganium antiquum from Fort Union Formation, Glendive Montana, USA, by Omar Hoftun.JPG
Fossils from the Fort Union Formation
Type Geological formation
Sub-unitsAtwell Gulch, China Butte, Ekalaka, Lebo, lower Ludlow, Overland, Rock Bench Quarry, Sentinel Butte, Shotgun, Somber beds, Tongue River, Tullock, upper Ludlow, Polecat Bench Formation
Underlies Wasatch Formation
Overlies Hell Creek Formation, Lance Formation
Lithology
Primary Sandstone, shale
Other Coal
Location
Coordinates 47°00′N104°36′W / 47.0°N 104.6°W / 47.0; -104.6
Approximate paleocoordinates 52°48′N80°06′W / 52.8°N 80.1°W / 52.8; -80.1
Region Montana, North Dakota
Wyoming, Colorado
CountryFlag of the United States.svg  United States
Extent Powder River Basin
Fort Union Formation - stratigraphy Coal Stratigraphy Powder River Basin.png
Fort Union Formation - stratigraphy

The Fort Union Formation is a geologic unit containing sandstones, shales, and coal beds in Wyoming, Montana, and parts of adjacent states. In the Powder River Basin, it contains important economic deposits of coal, uranium, and coalbed methane. [1]

Contents

Description

The Fort Union is mostly of Paleocene age and represents a time of extensive swamps as well as fluvial and lacustrine conditions. The rocks are more sandy in southwestern Wyoming and more coal-bearing in northeast Wyoming and southeast Montana, reflecting a general change from rivers and lakes in the west to swamps in the east, but all three environments were present at various times in most locations. [2]

Coal in the Fort Union in the Powder River Basin occurs mainly in the Tongue River Member, where as many as 32 coal seams total more than 300 feet in thickness. [1] One such bed, the Wyodak Coal near Gillette, Wyoming, is as much as 110 feet (34 m) thick. Most of the coals in the Fort Union Formation are ranked subbituminous. [3]

Fossil content

Color key
Taxon Reclassified taxonTaxon falsely reported as presentDubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Notes
Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Mammals

Cimolestans

Cimolestans reported from the Fort Union Formation
GenusSpeciesLocalityStratigraphic memberMaterialNotesImages
Crustulus C. fontanusNortheastern Montana. [4] Tullock Member. [4] An isolated upper molar. [4] A pantodont.

Leptictids

Leptictids reported from the Fort Union Formation
GenusSpeciesLocalityStratigraphic memberMaterialNotesImages
Prodiacodon P. crustulum Garfield & McCone counties, Montana. [5] Tullock Member. [5] Fragmentary dentary & isolated teeth. [5] A leptictid.

Marsupials

Marsupials reported from the Fort Union Formation
GenusSpeciesLocalityStratigraphic memberMaterialNotesImages
Peradectes P. sp.Swain Quarry, Wyoming. [6] Upper & lower molars. [6] Reassigned to Swaindelphys .
Swaindelphys S. cifelliiSwain Quarry, Wyoming. [6] Upper & lower molars. [6] An opossum.

Primatomorphs

Primatomorphs reported from the Fort Union Formation
GenusSpeciesLocalityStratigraphic memberMaterialNotesImages
Carpodaptes C. sp. Wind River Basin, Wyoming. [7] Shotgun Member. [7] 2 isolated fourth lower premolars. [7] A carpolestid.
Carpodaptes aulacodon.jpg
Chiromyoides C. caesorHell's Half Acre (UCM locality 78009), Mesa County, Colorado. [8] A single upper incisor (UCM 53515). [8] A plesiadapid.
C. gigas Piceance Creek Basin, Colorado. [8] Multiple teeth. [8] A plesiadapid.
C. sp.UCM locality 78060, Colorado. [8] A left molar (UCM 41606). [8] A plesiadapid.
Elphidotarsius E. shotgunensis Wind River Basin, Wyoming. [7] Shotgun Member. [7] Right ramus of mandible & isolated teeth. [7] A carpolestid.
Nannodectes N. gazini Fremont County, Colorado. [8] A right maxilla (USGS 16872). [8] A plesiadapid.
Palaechthon P., near P. alticuspis Wind River Basin, Wyoming. [7] Shotgun Member. [7] 3 upper molars & 4 lower molars. [7] A plesiadapiform.
P. woodi Wind River Basin, Wyoming. [7] Shotgun Member. [7] A lower jaw & 13 isolated teeth. [7] A plesiadapiform.
Palenochtha P. cf. minor Wind River Basin, Wyoming. [7] Shotgun Member. [7] 5 lower teeth. [7] A plesiadapiform.
Paromomys P., near P. depressidens Wind River Basin, Wyoming. [7] Shotgun Member. [7] Approximately 12 upper teeth, 8 isolated lower teeth & a jaw fragment. [7] A paromomyid.
Phenacolemur P. fremontensis Wind River Basin, Wyoming. [7] Shotgun Member. [7] A lower jaw & isolated teeth. [7] A paromomyid.
P. cf. frugivorus Wind River Basin, Wyoming. [7] Shotgun Member. [7] 2 upper molars & 8 isolated lower molars. [7] A paromomyid.
Plesiadapis P. dubius Piceance Creek Basin, Colorado. [8] Jaw elements & teeth. [8] A plesiadapid.
Plesiadapis sp. - MUSE.JPG
P. fodinatus Piceance Creek Basin, Colorado. [8] Jaw elements & teeth. [8] A plesiadapid.
P. sp. Wind River Basin, Wyoming. [7] Shotgun Member. [7] 5 lower molars, 3 anterior upper molars & a premolar. [7] A plesiadapid.
Plesiadapis NT.jpg
Plesiolestes P. cf. problematicus Wind River Basin, Wyoming. [7] Shotgun Member. [7] Approximately 45 isolated teeth. [7] A plesiadapiform.
Pronothodectes P. intermedius Wind River Basin, Wyoming. [7] Shotgun Member. [7] Jaw elements & teeth. [7] A plesiadapid.
Purgatorius P. janisae'Harley's Point’ UCMP locality V77087, Garfield County, Montana. [9] Tullock Member. [9] UCMP 150018 (right m1), and UCMP 192398 (left m3). [9] A purgatoriid.
P. mckeeveri Garfield County, Montana. [9] Tullock Member. [9] Dentary remains & teeth. [9] A purgatoriid.
P. cf. P. mckeeveriHarley's Point’ UCMP locality V77087, Garfield County, Montana. [9] Tullock Member. [9] UCMP 150019 (right M2), and UCMP 150020 (right M2). [9] A purgatoriid.
Torrejonia Cf. T. wilsoni Wind River Basin, Wyoming. [7] Shotgun Member. [7] About 14 lower teeth & possibly 3 upper molars. [7] A plesiadapiform.
Zanycteris Z. honeyiUMC locality number 92177, Colorado. [10] Atwell Gulch Member. [10] Right maxilla (UCM 87378). [10] A plesiadapiform.

Ungulates

Ungulates reported from the Fort Union Formation
GenusSpeciesLocalityStratigraphic memberMaterialNotesImages
Dissacus D. argenteusPrinceton Quarry, Park County, Wyoming. [11] Upper part of the formation. [11] Jaw elements & teeth. [11] A mesonychid.
D. cf. navajoviusPrinceton Quarry, Park County, Wyoming. [11] Upper part of the formation. [11] Jaw elements & teeth. [11] Specimens reassigned to D. argenteus.
D. praenuntius Park County, Wyoming. [11] Upper part of the formation. [11] Mandible (YPM-PU 16159). [11] A mesonychid also known from the Willwood Formation.
Ectocion E. mediotuberPrinceton Quarry, Wyoming. [12] Dentary. [12] A phenacodontid.
Periptychus P. carinidens Makoshika State Park, Montana. [13] A periptychid also found in the Nacimiento, North Horn, Black Peaks & Animas formations.
Periptychus skeletal.PNG
Sigynorum S. magnadivisus Great Divide Basin, southern Wyoming. [14] China Butte Member. [14] An arctocyonid.

Reptiles

Birds

A partial ornithurine coracoid bone found in this formation is identical to others found in the older Hell Creek Formation. At present, this unnamed species is the only known individual bird species that have survived the Cretaceous–Paleogene extinction event. [15]

Birds reported from the Fort Union Formation
GenusSpeciesLocalityStratigraphic memberMaterialNotesImages
Lithornis L. celetiusBangtail Quarry, Sedan Quadrangle, Park County, Montana. [16] A lithornithid.
Lithornis.png

Crocodilians

Crocodilians reported from the Fort Union Formation
GenusSpeciesLocationStratigraphic memberMaterialNotesImages
Allognathosuchus A. sp.Princeton Quarry, Park County, Wyoming. [17] Anterior end of left dentary (PU 16988). [17] A crocodilian.
Allognathosuchus gracilis.jpg

Squamates

Squamates reported from the Fort Union Formation
GenusSpeciesLocalityStratigraphic memberMaterialNotesImages
Anguidae Genus & species indeterminateSwain Quarry, Carbon County, Wyoming. [18] Fragmentary jaw elements. [18] An anguid lizard.
cf. Anguidae Swain Quarry, Carbon County, Wyoming. [18] 6 partial dentaries. [18] Provisionally referred to anguid lizards based on size & shape.
Contogenys cf. C. sloaniSwain Quarry, Carbon County, Wyoming. [18] Posterior part of a right maxilla (AMNH 12069). [18] A skink.
Exostinus E. cf. E. lancensisSwain Quarry, Carbon County, Wyoming. [18] 4 partial dentaries. [18] A xenosaurid lizard.
E. rugosusPrinceton & Schaff quarries, Park County, Wyoming. [17] Multiple specimens. [17] A xenosaurid lizard.
Glyptosaurinae Genus & species indeterminateSwain Quarry, Carbon County, Wyoming. [18] Several jaw remains. [18] A glyptosaurine lizard.
Glyptosaurinae or Odaxosaurinae Genus & species indeterminateSwain Quarry, Carbon County, Wyoming. [18] Fragmentary jaw elements & osteoderms. [18] Indeterminate lizard remains.
Machaerosaurus M. torrejonensisSwain Quarry, Carbon County, Wyoming. [18] Numerous jaw elements. [18] An anguid lizard also known from the Nacimiento Formation.
Odaxosaurus O. pigerSwain Quarry, Carbon County, Wyoming. [18] Many fragmentary jaw remains. [18] An anguid lizard.
Oligodontosaurus O. wyomingensis Park County, Wyoming. [17] A left mandible (PU 14246). [17] An amphisbaenian.
Palaeosaniwa cf. P. canadensisSwain Quarry, Carbon County, Wyoming. [18] Medial part of left dentary (AMNH 15957). [18] A large anguimorph lizard.
Palaeoxantusia P. feraSwain Quarry, Carbon County, Wyoming. [18] Numerous jaw elements. [18] A night lizard.
Pancelosaurus P. pigerPrinceton, Fritz & Schaff quarries, Park County, Wyoming. [17] Multiple skull elements. [17] An anguid lizard.
Provaranosaurus P. acutusPrinceton Quarry, Park County, Wyoming. [17] PU 14243 (left maxilla), 14561 (anterior portion of left dentary) & 17145 ( fragment of left maxilla). [17] A palaeovaranid lizard.
cf. P. sp.Swain Quarry, Carbon County, Wyoming. [18] 3 partial dentaries (AMNH 14306, 14307 & 14309). [18] A palaeovaranid lizard.
Rhineuridae Unidentified genus & speciesFritz Quarry, Park County, Wyoming. [17] An almost complete right dentary & a broken vertebra (PU 18627). [17] An amphisbaenian.
Saniwa cf. S. sp.Swain Quarry, Carbon County, Wyoming. [18] 2 trunk vertebrae (AMNH 15960 & 16003). [18] A varanid.
Swainiguanoides S. milleriSwain Quarry, Carbon County, Wyoming. [18] Jaw elements. [18] An iguanid.

Testudines

Testudines reported from the Fort Union Formation
GenusSpeciesLocalityStratigraphic memberMaterialNotesImages
Atoposemys A. entopterosMontana. [19] Tullock Member. [19] A softshell turtle.
Axestemys A. montinsanaPTRM Site V02017, Slope County, North Dakota. [20] Numerous skull, limb & shell fragments. [20] A softshell turtle also found in the Melville & Denver formations.
Cardiochelyon C. rogerwoodiReis Quarry, Park County, Wyoming. [21] Partial skeleton (YPM PU14671). [21] A kinosternoid formerly thought to be a platysternid.
Cedrobaena C. putoriusCedar Point Quarry, Wyoming. [22] Shell & skull elements. [22] A baenid turtle also found in the Hell Creek Formation.
Cedrobaena putorius.jpg
Hutchemys H. arctochelysBurns Mine, Washoe Area, Carbon County, Montana. [23] Tongue River Member. [23] Multiple shell elements. [23] A softshell turtle.
H. rememdium Fallon County, Montana. [23] Ekalaka Member. [23] A near complete postcranial skeleton (YPM PU 16795) & shell elements. [23] A softshell turtle.
H. sp.Duffy's Ranch, Sweet Grass County, Montana. [23] YPM PU 11566. [23] A softshell turtle.
Ptychogaster P. sp.Princeton Quarry & Reiss Locality, Park County, Wyoming. [17] PU 17794 (fragments of the skull & shell), 14671 & 16443 (shells). [17] A turtle.
Tullochelys T. montanusMontana. [19] Tullock Member. [19] A chelydrid turtle also known from the Hell Creek Formation.

Amphibians

Amphibians reported from the Fort Union Formation
GenusSpeciesLocalityStratigraphic memberMaterialNotesImages
Amphiuma A. jepseni Park County, Wyoming. [17] PU 14666 (partial vertebral column), 14668 (partial skull) & 16788 (dislocated vertebrae). [17] An aquatic salamander.
Anura Incertae sedis Park County, Wyoming. [17] PU 14662 (distal end of right radioulna), 14663 (proximal end of left radioulna), 14669 (phalanx), 13372 (right maxilla). [17] A frog.
Discoglossidae Undescribed genus & species Park County, Wyoming. [17] Distal end of right humerus (PU 14670). [17] A frog similar to undescribed discoglossid remains from the Hell Creek Formation. [17]
Eorhinophrynus E. sp.Princeton & Fritz quarries, Park County, Wyoming. [17] Humeri & vertebrae. [17] A burrowing toad.
Opisthotriton O. kayiPrinceton Quarry, Park County, Wyoming. [17] Multiple specimens. [17] A salamander.
Scapherpeton S. tectumPrinceton & Schaff quarries, Park County, Wyoming. [17] PU 20583 (3 broken vertebrae, an atlas, an ilium & a rib) & PU 19500 (a humerus). [17] A salamander.
Scapherpeton.jpg

Fish

Fish reported from the Fort Union Formation
GenusSpeciesLocalityStratigraphic memberMaterialNotesImages
Acipenseridae Morphotype AEagle Mine near Bear Creek, Carbon County, Montana. [24] A complete lateral scute (YPM VPPU 17066). [24] A large sturgeon.
Morphotype BHighway Blowout Site, Fallon County, Montana. [24] Tongue River Member. [24] A complete lateral scute (YPM VPPU 16646). [24] A large sturgeon.
Amia A. basiloides Burns Mine and Eagle Mine near Bear Creek, Carbon County, Montana [25] A near complete skull and partial skeleton, isolated vertebra [25] A large bowfin.
Atractosteus A. grandei Bowman County, North Dakota. [26] Lowest Danian strata. [26] A large gar.
Cyclurus C. fragosusSchaff Quarry, Park County, Wyoming. [17] 3 vertebral centra (PU 21174). [17] A bowfin.
Engdahlichthys E. milviaegisMontana. [27] Tullock Member. [27] A fairly small sturgeon.
Polyodon P. tuberculataMontana. [27] Tullock Member. [27] 3 specimens. [27] A paddlefish.

Invertebrates

Bivalves

Bivalves reported from the Fort Union Formation
GenusSpeciesLocalityStratigraphic memberMaterialNotesImages
Pisidium P. sp. indet. Powder River Basin. [28] Tongue River Member. [28] 8 specimens. [28] A sphaeriid.
P.? sp. indet. Powder River Basin. [28] Tongue River Member. [28] 3 specimens. [28] A sphaeriid.
Plesielliptio P. priscus Powder River Basin. [28] Tongue River Member. [28] Numerous specimens. [28] A unionid.
cf. P. priscus Powder River Basin. [28] Tongue River Member. [28] Several specimens. [28] A unionid.
P. silberlingi Powder River Basin. [28] Tongue River Member. [28] Numerous specimens. [28] A unionid.
cf. P. silberlingi Powder River Basin. [28] Tongue River Member. [28] 6 specimens. [28] A unionid.
P. sp. indet. Powder River Basin. [28] Tongue River Member. [28] 2 specimens. [28] A unionid.
Sphaeriidae Gen. & sp. indet. Powder River Basin. [28] Tongue River Member. [28] Numerous specimens. [28] A sphaeriid.
Sphaerium S. sp. indet. Powder River Basin. [28] Tongue River Member. [28] 1 specimen. [28] A sphaeriid.
S.? sp. indet. Powder River Basin. [28] Tongue River Member. [28] Several specimens. [28] A sphaeriid.
Unionidae Gen. & sp. indet. Powder River Basin. [28] Tongue River Member. [28] 11 specimens. [28] A unionid.

Gastropods

Gastropods reported from the Fort Union Formation
GenusSpeciesLocalityStratigraphic memberMaterialNotesImages
Acroloxus A.? minutus Powder River Basin. [28] Tongue River Member. [28] 2 specimens. [28] A river limpet.
A. sp. indet. Powder River Basin. [28] Tongue River Member. [28] 1 specimen. [28] A river limpet.
Clenchiella C. n. sp. A Powder River Basin. [28] Tongue River Member. [28] Numerous specimens. [28] A clenchiellid.
C. n. sp. A? Powder River Basin. [28] Tongue River Member. [28] 1 specimen. [28] A clenchiellid.
C. cf. C. n. sp. A Powder River Basin. [28] Tongue River Member. [28] 10 specimens. [28] A clenchiellid.
C. sp. indet. Powder River Basin. [28] Tongue River Member. [28] 30 specimens. [28] A clenchiellid.
Hydrobia H. anthonyi Powder River Basin. [28] Tongue River Member. [28] 2 specimens. [28] A hydrobiid.
H. sp. A Powder River Basin. [28] Tongue River Member. [28] Numerous specimens. [28] A hydrobiid.
H. cf. H. sp. A Powder River Basin. [28] Tongue River Member. [28] 2 specimens. [28] A hydrobiid.
H. sp. B? Powder River Basin. [28] Tongue River Member. [28] Multiple specimens. [28] A hydrobiid.
H. sp. C? Powder River Basin. [28] Tongue River Member. [28] 1 specimen. [28] A hydrobiid.
H. sp. indet. Powder River Basin. [28] Tongue River Member. [28] Multiple specimens. [28] A hydrobiid.
H.? sp. indet. Powder River Basin. [28] Tongue River Member. [28] 2 specimens. [28] A hydrobiid.
Lioplacodes L. multistriata Powder River Basin. [28] Tongue River Member. [28] Numerous specimens. [28] A viviparid.
L. tenuicarinata Powder River Basin. [28] Tongue River Member. [28] Numerous specimens. [28] A viviparid.
L. tenuicarinata? Powder River Basin. [28] Tongue River Member. [28] 11 specimens. [28] A viviparid.
L. limneaformis Powder River Basin. [28] Tongue River Member. [28] Numerous specimens. [28] A viviparid.
L. sp. indet. Powder River Basin. [28] Tongue River Member. [28] Numerous specimens. [28] A viviparid.
L.? sp. indet. Powder River Basin. [28] Tongue River Member. [28] 1 specimen. [28] A viviparid.
Valvata?V.? sp. indet. Powder River Basin. [28] Tongue River Member. [28] 1 specimen. [28] A valvatid.
Viviparus V. raynoldsanus Powder River Basin. [28] Tongue River Member. [28] Numerous specimens. [28] A viviparid.
V. raynoldsanus? Powder River Basin. [28] Tongue River Member. [28] 1 specimen. [28] A viviparid.
V. cf. V. raynoldsanus Powder River Basin. [28] Tongue River Member. [28] 17 specimens. [28] A viviparid.
V. sp. Powder River Basin. [28] Tongue River Member. [28] Multiple specimens. [28] A viviparid.

Plants

Plants reported from the Fort Union Formation
GenusSpeciesLocalityStratigraphic memberMaterialNotesImages
Aesculus A. hickeyi Custer National Forest, Powder River County, Montana. [29] Tongue River Member. [29] Leaves. [29] A horse chestnut.
Amersinia A. obtrullata Custer National Forest, Powder River County, Montana. [29] Tongue River Member. [29] Fruits. [29] A nyssaceaen, may be produced by the same plant as Beringiaphyllum cupanioides.
Beringiaphyllum B. cupanioides Custer National Forest, Powder River County, Montana. [29] Tongue River Member. [29] Leaf (UF 18969-60464). [29] A nyssaceaen, may be produced by the same plant as Amersinia obtrullata.
Browniea B. serrataMexican Hat locality & Custer National Forest, Powder River County, Montana. [29] [30] Lebo Member & Tongue River Member. [29] [30] Leaves showing signs of insect damage. [30] A nyssaceaen.
Cercidiphyllum C. genetrixMexican Hat locality, Montana. [30] Lebo Member. [30] Leaves showing signs of insect damage. [30] A katsura tree.
Cornus C. swingii Custer National Forest, Powder River County, Montana. [29] Tongue River Member. [29] Leaves. [29] A dogwood.
Davidia D. antiquaCuster National Forest, Powder River County, Montana. [29] Tongue River Member. [29] Leaves & fruits. [29] A dove tree.
Cf. Dennstaedtia Cf. D. americana Custer National Forest, Powder River County, Montana. [29] Tongue River Member. [29] A single specimen of sterile foliage (UF 18969-34532). [29] A fern.
Dicotylophyllum D. hansonium Williston Basin, North Dakota. [31] Tongue River Member. [31] Leaves. [31] A dicot.
D. horsecreekium Williston Basin, North Dakota. [31] Ludlow Member. [31] Leaves. [31] A dicot.
Eostangeria E. pseudopteris Sweetwater County, Wyoming. [32] Upper part of the formation. [32] Multiple specimens. [32] A cycad.
Equisetum E. sp.Custer National Forest, Powder River County, Montana. [29] Tongue River Member. [29] A single stem (UF 18969-60476A). [29] A horsetail.
"Ficus""F." artocarpoidesMexican Hat locality. [30] Lebo Member. [30] Leaves with signs of hole feeding and insect mining. [30] A fig-tree.
Glyptostrobus G. europaeusMexican Hat locality. [30] Lebo Member. [30] Leafy branches. [30] A conifer.
Juglandiphyllites J. glabraMexican Hat locality, Montana. [30] Lebo Member. [30] Leaves with insect damage and probable lepidopteran leaf mines. [30] A member of the walnut family.
Lauraceae Species 1Mexican Hat locality, Montana. [30] Lebo Member. [30] Leaf with piercing and sucking marks from insects. [30]
Species 2Mexican Hat locality, Montana. [30] Lebo Member. [30] Leaves showing signs of insect damage. [30]
Macginistemon M. mikanoidesCuster National Forest, Powder River County, Montana. [29] Tongue River Member. [29] Stamen groups. [29] A platanaceaen.
Macginitiea M. gracilis Custer National Forest, Powder River County, Montana. [29] Tongue River Member. [29] A fragmentary leaf (UF 18969-38380). [29] A platanaceaen.
M. nascens Williston Basin, North Dakota. [31] Ludlow Member. [31] Leaves. [31] A platanaceaen.
Meliosma M. thriviensis Williston Basin, North Dakota. [31] Ludlow Member. [31] Leaves. [31] A sabiaceaen.
M. vandaelium Williston Basin, North Dakota. [31] Tongue River Member. [31] Multiple leaves. [31] A sabiaceaen.
Nordenskioeldia N. borealisCuster National Forest, Powder River County, Montana. [29] Tongue River Member. [29] Fruit. [29] A trochodendrale.
Paleonelumbo P. macrolobaMexican Hat locality, Montana. [30] Lebo Member. [30] Leaves. [30] A nelumbonaceaen.
Paranymphaea P. crassifoliaMexican Hat locality, Montana. [30] Lebo Member. [30] Leaves. [30] A nymphaeaceaen.
Phyllites P. demoresiiCuster National Forest, Powder River County, Montana. [29] Tongue River Member. [29] Leaves. [29]
Platanus P. raynoldsiiMexican Hat locality, Montana. [30] Lebo Member. [30] Leaves showing signs of insect damage. [30] A plane-tree.
P. sp.Custer National Forest, Powder River County, Montana. [29] Tongue River Member. [29] Leaves. [29] A plane-tree.
Polyptera P. manningiiMexican Hat locality, Montana. [30] Lebo Member. [30] Fruits. [30] A member of the walnut family.
"Populus""P". nebrascensisMexican Hat locality, Montana. [30] Lebo Member. [30] Leaves showing signs of insect damage. [30] A poplar.
Porosia P. verrucosaCuster National Forest, Powder River County, Montana. [29] Tongue River Member. [29] Fruits. [29] A rutaceaen.
Taxodium T. olrikiiCuster National Forest, Powder River County, Montana. [29] Tongue River Member. [29] [29] A cypress tree.
Ternstromites cf. T. aureavallisMexican Hat locality, Montana. [30] Lebo Member. [30] Leaf with a gall at the intersection of primary and secondary veins. [30] A theaceaen.
T. paucimissouriensis Williston Basin, North Dakota. [31] Ludlow & Tongue River Members. [31] Leaves. [31] A theaceaen.
Trochodendroides T. genetrixCuster National Forest, Powder River County, Montana. [29] Tongue River Member. [29] A few leaves. [29] A saxifrage.
Ulmites U. microphyllaCuster National Forest, Powder River County, Montana. [29] Tongue River Member. [29] Leaves. [29] An ulmaceaen.
Zizyphoides Z. flabellaMexican Hat locality, Montana & Custer National Forest, Powder River County, Montana. [30] [29] Lebo Member & Tongue River Member. [30] [29] Leaves showing signs of insect damage. [30] A trochodendrale.

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

The Paleocene, or Palaeocene, is a geological epoch that lasted from about 66 to 56 million years ago (mya). It is the first epoch of the Paleogene Period in the modern Cenozoic Era. The name is a combination of the Ancient Greek παλαιός palaiós meaning "old" and the Eocene Epoch, translating to "the old part of the Eocene".

Hutchemys is an extinct genus of softshell turtles from the late Cretaceous to the late Paleocene of New Mexico, Montana, Wyoming, Utah, and North Dakota, United States. It was first named by Walter G. Joyce, Ariel Revan, Tyler R. Lyson and Igor G. Danilov in 2009, and the type species is Hutchemys rememdium. H. rememdium is known from the holotype YPM PU 16795, which consists of a nearly complete postcranial skeleton, and from the referred specimen YPM PU 16781, found in the Ekalaka Member of the Fort Union Formation, Montana. Another referred specimen, YPM PU 14985, was found in the Cedar Point Quarry, Wyoming. The second species, H. arctochelys, is known from the holotype YPM PU 16319, a nearly complete carapace, and from the paratypes YPM PU 16320, YPM PU 16321, YPM PU 16322, YPM PU 16238. All specimens of H. arctochelys were recovered from the same quarry of the Tongue River Member, Fort Union Formation, near Burns Mine of Montana. A possible third species is represented by the unnamed specimen UCMP 130000 from the Paleocene Tullock Formation of Montana. Aspideretes? nassau (YPM PU 11566) from the Fort Union Formation, Duffy's Ranch of Sweet Grass County, Montana was also assigned to Hutchemys sp. A fourth species of Hutchemys, Hutchemys walkerorum, has been uncovered from the Hell Creek Formation of North Dakota. H. walkerorum is known from the holotype BDM 063, identified by the discovery and assembly of portions of its carapace. The fossil of H. walkerorum suggests that it was the only Hutchemys to live exclusively during the late Cretaceous era.

The Willwood Formation is a sedimentary sequence deposited during the late Paleocene to early Eocene, or Clarkforkian, Wasatchian and Bridgerian in the NALMA classification.

The Hatchetigbee Bluff Formation is a geologic formation in Alabama, Georgia, Louisiana and Mississippi. The youngest unit of the Wilcox Group preserves fossils dating back to the Ypresian stage of the Eocene period, or Wasatchian in the NALMA classification. The formation is named for Hatchetigbee Bluff on the Tombigbee River, Washington County, Alabama.

<span class="mw-page-title-main">Tongue River Member</span> Geologic member in the Fort Union Formation

The Tongue River Member is the uppermost geologic member of the Fort Union Formation in Montana, North Dakota, Wyoming. The strata are yellow or light-colored massive sandstones and numerous thick coal beds.

The Sharps Formation is a geologic formation in South Dakota. It preserves fossils dating back to the Paleogene.

<span class="mw-page-title-main">Wasatch Formation</span> Geologic formation in the western United States

The Wasatch Formation (Tw) is an extensive highly fossiliferous geologic formation stretching across several basins in Idaho, Montana, Wyoming, Utah and western Colorado. It preserves fossils dating back to the Early Eocene period. The formation defines the Wasatchian or Lostcabinian, a period of time used within the NALMA classification, but the formation ranges in age from the Clarkforkian to Bridgerian.

The Washakie Formation is a geologic formation in northern Colorado and southern Wyoming. It preserves many mammal, bird, reptile and other fossils dating back to the Lutetian stage of the Eocene within the Paleogene period. The sediments fall in the Bridgerian and Uintan stages of the NALMA classification.

The Hoback Formation is a geologic formation in west-central Wyoming, located within the Hoback Basin. It formed as a result of increased sedimentation rates from the Laramide Orogeny and preserves fossils dating back to the late Paleogene period, through the early Eocene.

<span class="mw-page-title-main">Wind River Formation</span>

The Wind River Formation is a geologic formation in Wyoming in the Wind River Basin. It preserves fossils dating back to the Paleogene period. A recent study by Stanford suggests that fracking has contaminated the entire ground water resource in the basin.

<span class="mw-page-title-main">DeBeque Formation</span> Geologic formation in Colorado, United States

The DeBeque Formation is a geologic formation in Colorado's Piceance Basin, preserving fossils which date back to the Late Paleocene to Early Eocene period (Clarkforkian to Wasatchian in the NALMA classification. Examples of these fossils are held in the University of Colorado Museum of Natural History.

<span class="mw-page-title-main">San Jose Formation</span> A geologic formation in New Mexico

The San Jose Formation is an Early Eocene geologic formation in the San Juan Basin of New Mexico and Colorado.

The Sheep Pass Formation is a geologic formation in Nevada. It preserves fossils dating back to the Paleogene period.

The Margaret Formation is a geologic formation of the Eureka Sound Group in the Sverdrup Basin in Northwest Territories and Nunavut, Canada. The unit belonging to the Eureka Sound Group which crops out at Ellesmere Island preserves fossils dating back to the Early Eocene period, or Wasatchian in the NALMA classification.

<i>Viverravus</i> Extinct genus of mammals

Viverravus is an extinct genus of placental mammals from extinct subfamily Viverravinae within extinct family Viverravidae, that lived in North America, Europe and Asia from the middle Paleocene to middle Eocene.

Chiromyoides is a small plesiadapid primatomorph that is known for its unusually robust upper and lower incisors, deep dentary, and comparatively small cheek teeth. Species of Chiromyoides are known from the middle Tiffanian through late Clarkforkian North American Land Mammal Ages (NALMA) of western North America, and from late Paleocene deposits in the Paris Basin, France.

<span class="mw-page-title-main">Nyctitheriidae</span> Family of extinct eulipotyphlan insectivores from the Paleocene and Eocene

Nyctitheriidae is a family of extinct eulipotyphlan insectivores known from the Paleocene and Eocene epochs of North America and Asia and persisting into the Oligocene of Europe. Several genera, including Nyctitherium, Paradoxonycteris, and Wyonycteris, have initially been described as bats, although the family is more frequently placed in the order Eulipotyphla.

<span class="mw-page-title-main">Salamanca Formation</span> Geologic formation in Chubut Province, Argentina

The Salamanca Formation is a geologic formation in the Golfo San Jorge Basin of central Patagonia that yields well-preserved, well-dated fossils from the early Paleocene. Studies of these fossils are providing new data on plant and animal diversity following the end-Cretaceous extinction event.

References

  1. 1 2 Wyodak Coal, Tongue River Member of the Fort Union Formation, Powder River Basin, Wyoming: "No-Coal Zones" and Their Effects on Coalbed Methane Production, by Mark Ashley, 2005
  2. Eocene and Paleocene rocks of the southern and central basins, by Robert E. McDonald, in Geologic Atlas of the Rocky Mountain Region, Rocky Mountain Association of Geologists, Denver, CO, 1972: p. 248
  3. Cretaceous and Tertiary coals of the Rocky Mountains and Great Plains regions, by R.M. Flores and T.A. Cross, 1991, in Economic Geology, U.S., Geological Society of America, Decade of North American Geology Series, vol. P-2, p. 547-571.
  4. 1 2 3 Clemens, William A. (2018-02-17). "A pantodont (Mammalia) from the latest Puercan North American Land Mammal Age (earliest Paleocene) of the Western Interior, USA". Historical Biology. 30 (1–2): 183–188. Bibcode:2018HBio...30..183C. doi:10.1080/08912963.2016.1276178. ISSN   0891-2963. S2CID   132830375.
  5. 1 2 3 Clemens, W. (January 9, 2015). "(Leptictidae, Mammalia) from the Tullock Member of the Fort Union Formation, Garfield and McCone Counties, Montana, USA". PaleoBios. 32 (1): 1–17. doi: 10.5070/P9321025382 . S2CID   55974838.
  6. 1 2 3 4 Johanson, Zerina (November 1996). "New marsupial from the Fort Union Formation, Swain Quarry, Wyoming". Journal of Paleontology. 70 (6): 1023–1031. Bibcode:1996JPal...70.1023J. doi:10.1017/S0022336000038725. ISSN   0022-3360. S2CID   133554548.
  7. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 Gazin, C. Lewis (1971). "Paleocene primates from the shotgun member of the Fort Union Formation in the Wind River Basin, Wyoming". Proceedings of the Biological Society of Washington. 84: 13–37. ISSN   0006-324X.
  8. 1 2 3 4 5 6 7 8 9 10 11 12 Burger, Benjamin J.; Honey, James G. (2008-09-12). "Plesiadapidae (Mammalia, Primates) from the late Paleocene Fort Union Formation of the Piceance Creek Basin, Colorado". Journal of Vertebrate Paleontology. 28 (3): 816–825. doi:10.1671/0272-4634(2008)28[816:pmpftl]2.0.co;2. ISSN   0272-4634. S2CID   128913932.
  9. 1 2 3 4 5 6 7 8 9 Wilson Mantilla, Gregory P.; Chester, Stephen G. B.; Clemens, William A.; Moore, Jason R.; Sprain, Courtney J.; Hovatter, Brody T.; Mitchell, William S.; Mans, Wade W.; Mundil, Roland; Renne, Paul R. (2021). "Earliest Palaeocene purgatoriids and the initial radiation of stem primates". Royal Society Open Science. 8 (2): 210050. Bibcode:2021RSOS....810050W. doi:10.1098/rsos.210050. ISSN   2054-5703. PMC   8074693 . PMID   33972886.
  10. 1 2 3 Burger, Benjamin John (2013-10-29). "A new species of the archaic primate Zanycteris from the late Paleocene of western Colorado and the phylogenetic position of the family Picrodontidae". PeerJ. 1: e191. doi: 10.7717/peerj.191 . ISSN   2167-8359. PMC   3817582 . PMID   24255808.
  11. 1 2 3 4 5 6 7 8 9 O'Leary, Maureen A.; Rose, Kenneth D. (1995-05-12). "New mesonychian dentitions from the Paleocene and Eocene of the Bighorn Basin, Wyoming". Annals of the Carnegie Museum. 64 (2): 147–172. doi: 10.5962/p.215127 . ISSN   0097-4463. S2CID   89955337.
  12. 1 2 Thewissen, J. G. M. (1990). "Evolution of Paleocene and Eocene Phenacodontidae (Mammalia, Condylarthra)". hdl:2027.42/48629.{{cite journal}}: Cite journal requires |journal= (help)
  13. Shelley, Sarah L.; Williamson, Thomas E.; Brusatte, Stephen L. (2018-07-18). "The osteology of Periptychus carinidens: A robust, ungulate-like placental mammal (Mammalia: Periptychidae) from the Paleocene of North America". PLOS ONE. 13 (7): e0200132. Bibcode:2018PLoSO..1300132S. doi: 10.1371/journal.pone.0200132 . ISSN   1932-6203. PMC   6051615 . PMID   30020948.
  14. 1 2 McComas, Katie M.; Eberle, Jaelyn J. (May 2015). "A new earliest Paleocene (Puercan) arctocyonid mammal from the Fort Union Formation, Great Divide Basin, Wyoming, and its phylogenetic position among early 'condylarths'". Journal of Systematic Palaeontology. 14 (6): 445–459. doi:10.1080/14772019.2015.1066886. S2CID   127411164.
  15. Longrich, N.R., Tokaryk, T. and Field, D.J. (2011). "Mass extinction of birds at the Cretaceous–Paleogene (K–Pg) boundary." Proceedings of the National Academy of Sciences, 108(37): 15253-15257. doi : 10.1073/pnas.1110395108
  16. Houde, Peter W. (1988). "Paleognathous Birds from the Early Tertiary of the Northern Hemisphere". The Auk. 107 (2): 455–456. doi:10.2307/4087644. ISSN   0004-8038. JSTOR   4087644.
  17. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 Estes, Richard (1975). "Lower Vertebrates from the Fort Union Formation, Late Paleocene, Big Horn Basin, Wyoming". Herpetologica. 31 (4): 365–385. ISSN   0018-0831. JSTOR   3891523.
  18. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 Sullivan, Robert M. (January 1982). "Fossil lizards from Swain Quarry "Fort Union Formation," middle Paleocene (Torrejonian), Carbon County, Wyoming". Journal of Paleontology. 56 (4): 996–1010.
  19. 1 2 3 4 Hutchison, J. Howard (2013), Brinkman, Donald B.; Holroyd, Patricia A.; Gardner, James D. (eds.), "New Turtles from the Paleogene of North America", Morphology and Evolution of Turtles, Vertebrate Paleobiology and Paleoanthropology, Dordrecht: Springer Netherlands, pp. 477–497, doi:10.1007/978-94-007-4309-0_26, ISBN   978-94-007-4309-0 , retrieved 2022-11-19
  20. 1 2 Vitek, Natasha S. (2012-03-11). "Giant fossil soft-shelled turtles of North America". Palaeontologia Electronica. 15 (16): 1–43. doi: 10.26879/299 . ISSN   1094-8074.
  21. 1 2 Joyce, Walter G.; Claude, Julien (2020-01-15). "An alternative interpretation of the Paleogene turtle Cardichelyon rogerwoodi as a hinged kinosternoid". Journal of Paleontology. 94 (3): 557–567. Bibcode:2020JPal...94..557J. doi: 10.1017/jpa.2019.92 . ISSN   0022-3360. S2CID   210976208.
  22. 1 2 Lyson, Tyler R.; Joyce, Walter G. (November 2009). "A revision of Plesiobaena (Testudines: Baenidae) and an assessment of baenid ecology across the K/T boundary". Journal of Paleontology. 83 (6): 833–853. doi:10.1666/09-035.1. ISSN   0022-3360. S2CID   85964417.
  23. 1 2 3 4 5 6 7 8 Joyce, Walter G.; Revan, Ariel; Lyson, Tyler R.; Danilov, Igor G. (2009). "Two New Plastomenine Softshell Turtles from the Paleocene of Montana and Wyoming". Bulletin of the Peabody Museum of Natural History. 50 (2): 307. doi:10.3374/014.050.0202. ISSN   0079-032X. S2CID   85505337.
  24. 1 2 3 4 5 Brownstein, Chase Doran (November 2022). "Evidence of large sturgeons in the Paleocene of North America". Journal of Paleontology. 97: 218–222. doi: 10.1017/jpa.2022.87 . ISSN   0022-3360. S2CID   253653018.
  25. 1 2 Brownstein, Chase D.; Near, Thomas J. (2024). "A giant bowfin from a Paleocene hothouse ecosystem in North America". Zoological Journal of the Linnean Society. doi:10.1093/zoolinnean/zlae042 . Retrieved 2024-04-30.
  26. 1 2 Brownstein, Chase Doran; Lyson, Tyler R. (2022). "Giant gar from directly above the Cretaceous–Palaeogene boundary suggests healthy freshwater ecosystems existed within thousands of years of the asteroid impact". Biology Letters. 18 (6): 20220118. doi:10.1098/rsbl.2022.0118. PMC   9198771 . PMID   35702983.
  27. 1 2 3 4 5 Murray, Alison M.; Brinkman, Donald B.; DeMar, David G.; Wilson, Gregory P. (2020-03-03). "Paddlefish and sturgeon (Chondrostei: Acipenseriformes: Polyodontidae and Acipenseridae) from lower Paleocene deposits of Montana, U.S.A." Journal of Vertebrate Paleontology. 40 (2): e1775091. Bibcode:2020JVPal..40E5091M. doi:10.1080/02724634.2020.1775091. ISSN   0272-4634. S2CID   222213273.
  28. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 Hanley, John H.; Flores, Romeo M. (1987). "Taphonomy and Paleoecology of Nonmarine Mollusca: Indicators of Alluvial Plain Lacustrine Sedimentation, Upper Part of the Tongue River Member, Fort Union Formation (Paleocene), Northern Powder River Basin, Wyoming and Montana". PALAIOS. 2 (5): 479–496. Bibcode:1987Palai...2..479H. doi:10.2307/3514619. ISSN   0883-1351. JSTOR   3514619.
  29. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 Manchester, Steven R.; Foster, Alyssa; Lott, Terry A. (2023-05-12). "The Paleocene Horse Creek florule, Tongue River Member of the Fort Union Formation, southeastern Montana, USA". Acta Palaeobotanica. 63 (1): 32–53. doi: 10.35535/acpa-2023-0003 . ISSN   0001-6594.
  30. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 Donovan, Michael P.; Wilf, Peter; Labandeira, Conrad C.; Johnson, Kirk R.; Peppe, Daniel J. (2014-07-24). "Novel Insect Leaf-Mining after the End-Cretaceous Extinction and the Demise of Cretaceous Leaf Miners, Great Plains, USA". PLOS ONE. 9 (7): e103542. Bibcode:2014PLoSO...9j3542D. doi: 10.1371/journal.pone.0103542 . ISSN   1932-6203. PMC   4110055 . PMID   25058404.
  31. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Peppe, Daniel J.; Hickey, Leo J. (November 2014). "Fort Union Formation Fossil Leaves (Paleocene, Williston Basin, North Dakota, USA) Indicate Evolutionary Relationships Between Paleocene and Eocene Plant Species". Bulletin of the Peabody Museum of Natural History. 55 (2): 171–189. doi:10.3374/014.055.0209. ISSN   0079-032X. S2CID   129724520.
  32. 1 2 3 Kvaček, Zlatko; Manchester, Steven R. (1999). "Eostangeria Barthel (Extinct Cycadales) from the Paleogene of Western North America and Europe". International Journal of Plant Sciences. 160 (3): 621–629. doi:10.1086/314152. ISSN   1058-5893. S2CID   83978433.