Cretaceous marine turtles from the Western Interior Seaway of Canada

1990 ◽  
Vol 27 (10) ◽  
pp. 1288-1298 ◽  
Author(s):  
Elizabeth L. Nicholls ◽  
Tim T. Tokaryk ◽  
Len V. Hills
Keyword(s):  
Relative Abundance ◽  
Late Cretaceous ◽  
Taxonomic Diversity ◽  
Western Interior Seaway ◽  
Niobrara Formation ◽  
Marine Turtles ◽  
Pierre Shale ◽  
Northern Areas ◽  
Lower Campanian ◽  
Upper Campanian

Late Cretaceous marine turtles are rare in Canada, but specimens are known from three formations: Toxochelys latiremis Cope and Protostega sp. from the Pierre Shale, Pembina Member (lower Campanian); Lophochelys niobrarae Zangerl and Chelonioidea genus indet. from the Bearpaw Formation (upper Campanian); Protostegidae genus indet. and one other taxon from the Niobrara Formation (Coniacian).The Canadian records of the listed taxa constitute the northernmost limits of their known range and may represent their northern limits in the Cretaceous inland sea. Taxonomic diversity and relative abundance of turtles in the Canadian samples are significantly less than in comparable faunas to the south. Cool marine climates may have excluded local nesting and discouraged migrations into northern areas.

scholarly journals Late Cretaceous non-marine turtles of Asia: a review of taxonomic diversity and paleobiogeography

2015 ◽  
Author(s):  
Igor Danilov ◽  
Ekaterina Obraztsova ◽  
Vladimir Sukhanov
Keyword(s):  
Late Cretaceous ◽  
Environmental Conditions ◽  
Geographical Area ◽  
Temporal Distribution ◽  
Taxonomic Diversity ◽  
Coastal Areas ◽  
Marine Turtle ◽  
Marine Turtles ◽  
Middle Asia ◽  
Different Ages

Background. This report reviews data on taxonomic diversity and paleobiogeography of Late Cretaceous (K2) non-marine turtles of Asia accumulated since latest reviews in 2000s. K2 non-marine turtles of Asia are known from four main geographical areas: Middle Asia-Kazakhstan (MAK), Mongolia (MO), China (CH) and Japan (JA). Methods. We critically reviewed composition of non-marine turtle assemblages of the K2 for each of the mentioned geographical area to make estimates of taxonomic diversity for different ages of the K2. Based on these data we analyzed temporal distribution of taxa of non-marine turtles and change in taxonomic diversity of turtle assemblages. Results. K2 turtles of MAK are represented by eight suprageneric taxa – Adocidae (Ad), Carettochelyidae (Ca), Lindholmemydidae (Li), Macrobaenidae (Ma), Nanhsiungchelyidae (Na), Trionychidae (Tr), Eucryptodira indet. (Eu), and Testudines indet. (Te), of which Ad, Li, Ma and Tr are known from the Cenomanian(CE) – early Campanian(CA), whereas other taxa only from the CE-early Turonian(TU). Taxonomic diversity changes from 10–12 species and genera, 6–8 suprageneric taxa in the CE to 7 species and genera, 4 families in the late TU early CA. K2 turtles of MO are represented by seven suprageneric taxa – Ad, Ca, Li, Ma, Meiolaniformes (Me), Na, and Tr, of which Li, Na and Tr are known from the CE-Maastrichtian(MA), Ad, Ca, and Ma, from the CE-Santonian(SA), and Me, only from the MA. Taxonomic diversity changes from 12 species, 10 genera, 6 families in the CE – SA, 8–9 species, 7–9 genera, 3 families in the CA, and 9 species, 7–8 genera, and 4 suprageneric taxa in the MA. K2 turtles of CH are represented by three suprageneric taxa (Li, Na, and Tr), but their precise temporal distribution is poorly known. Taxonomic diversity in the K2 is 12 species, 11–12 genera, and 3 families. K2 turtles of JA are represented by six suprageneric taxa (Ad, Ca, Na, Tr, Eu, and Te), of which Na are known from the CE-SA, Tr from the Coniacian(CO)-CA, and other taxa from the CO-SA. Taxonomic diversity changes from 1 species, genus, and family in the CE-TU to 7 species and genera, and 5–6 suprageneric taxa in the CO-SA. Discussion. In MAK, most significant transformation of turtle assemblages occurred in the CE-TU, whereas transformation in the SA-CA was less significant. On the contrary, in MO, most significant transformation occurred in the SA-CA, and less significant in the CA-MA.The patterns of transformation of the K2 turtle assemblages of CH and JA are not clear. The differences in the patterns of diversity and transformations of the K2 turtle assemblages in different geographical areas of Asia may be explained by different environmental conditions in these areas at that time and influence of such factors as transgressions in coastal areas (MAK and JA) and cooling and aridizations in inland areas (MO and CH).

Remains of Clidastes Cope, 1868, an unexpected mosasaur in the upper Campanian of NW Germany

2005 ◽  
Vol 84 (3) ◽  
pp. 213-220 ◽  
Author(s):  
M.W. Caldwell ◽  
C.G. Diedrich
Keyword(s):  
North America ◽  
Late Cretaceous ◽  
Vertebral Column ◽  
Gulf Coast ◽  
Anterior Part ◽  
Western Interior Seaway ◽  
Southern Sweden ◽  
Nw Germany ◽  
The Village ◽  
Upper Campanian

AbstractThe mosasaurine Clidastes sp. is recognised from cranial and post-cranial remains collected at four localities in NW Germany. Cranial material was found in pelagic turbiditic marls which crop out near the village of Beckum, while post-cranial skeletal elements were collected from sandy limestones exposed near the villages of Schöppingen, Coesfeld and Billerbeck. In stratigraphic order, the units producing these specimens of Clidastes are the Coesfeld, Baumberge and Beckum formations of late Campanian (Late Cretaceous) age. The cranial material comprises the anterior part of a skull and a single isolated tooth, while post-cranial bones comprise a few isolated vertebrae and a partial skeleton including forelimb bones and an articulated vertebral column. Clidastes is known to date from the western North Sea Basin (England), southern Sweden, as well as from North America (Western Interior Seaway and Gulf Coast).

Great Plains polygonal fault system as expressed in Saskatchewan: Late Cretaceous fault initiation and graben formation

2017 ◽  
Vol 54 (5) ◽  
pp. 477-493
Author(s):  
Andy St-Onge
Keyword(s):  
Great Plains ◽  
Late Cretaceous ◽  
Three Dimensional ◽  
Fault System ◽  
Western Interior Seaway ◽  
Niobrara Formation ◽  
Near Surface ◽  
M Current ◽  
Time Extension ◽  
Polygonal Fault

An extensive polygonal fault system (PFS) has been recognized in fine-grained Late Cretaceous sediments of the Western Interior Seaway of North America. Polygonal fault systems are pervasive organizations of nontectonic faults with fault traces that coalesce to form distinctive polygonal fault patterns. Interpretation of a three-dimensional seismic dataset from southeast Saskatchewan provides insight into fault initiation, timing, and geometry for the Great Plains PFS (GPPFS). Faulting initiates in the Niobrara Formation, with the largest fault throws occurring over Early Cretaceous Viking Formation sandstone accumulations, suggesting that drape compaction over the channel sand initiated some of the faulting. Above this, faulting increases in vertical offset, and the predominant fault strike angles change in the Lea Park, Belly River, and Bearpaw formations (all homotaxial to the Pierre Shale) throughout Campanian time. By late Bearpaw time, the initially almost random fault strike orientations change to well-defined northwest–southeast- and west–east-striking grabens. These grabens have up to 20 m of throw and can be 125 m wide and 900 m long at ∼400 m current depth. Predominant graben faults are the continuation of some of the deeper PFS faults. Moreover, the grabens are present over a Campanian clinoform bed and may be interpreted to indicate Bearpaw time extension tectonics that is local or regional in scale. The PFS helps to explain near-surface faulting observed in Late Cretaceous sediments in the Western Interior Seaway and could be used as a model to help explain Late Cretaceous geology, subsurface groundwater flow, and shallow natural gas reservoir continuity.

LATE CRETACEOUS METHANE SEEPS AS HABITATS FOR NEWLY HATCHED AMMONITES

Palaios ◽  
2020 ◽  
Vol 35 (3) ◽  
pp. 151-163 ◽  
Author(s):  
ALISON J. ROWE ◽  
NEIL H. LANDMAN ◽  
J. KIRK COCHRAN ◽  
JAMES D. WITTS ◽  
MATTHEW P. GARB
Keyword(s):  
Late Cretaceous ◽  
Isotope Composition ◽  
Anaerobic Oxidation Of Methane ◽  
Anaerobic Oxidation ◽  
Western Interior Seaway ◽  
Methane Seeps ◽  
Oxidation Of Methane ◽  
Pierre Shale ◽  
Size And Morphology ◽  
Δ13c And Δ18o

ABSTRACT Cold methane seeps were common in the Late Cretaceous Western Interior Seaway of North America. They provided a habitat for a diverse array of fauna including ammonites. Recent research has demonstrated that ammonites lived at these sites. However, it is still unknown if they hatched at the seeps or only arrived there later in ontogeny. To answer this question, we documented the abundance and size distribution of small specimens of Baculites and Hoploscaphites at eight seep sites in the Pierre Shale of South Dakota. The specimens of Hoploscaphites range from 0.8 to 8.1 mm in shell diameter, with most of them falling between 1 and 1.5 mm. The specimens of Baculites range from 0.7 to 19.2 mm in length, with most specimens falling between 6 and 8 mm. The small size and morphology of these specimens indicate that they are neanoconchs, that is, newly hatched individuals that lived for a short time after hatching. We also analyzed the isotope composition (δ13C and δ18O) of 12 small specimens of Baculites and one specimen of Hoploscaphites with excellent shell preservation from one seep deposit. The values of δ13C and δ18O range from -16.3 to -2.5‰ and -3.0 to -0.9‰, respectively. The values of δ18O translate into temperatures of 19–28°C, which are comparable to previous estimates of the temperatures of the Western Interior Seaway. The low values of δ13C suggest that the tiny animals incorporated carbon derived from anaerobic oxidation of 12C-enriched methane into their shells. Evidently, they must have lived in close proximity to seep fluids emerging at the sediment-water interface and the associated microbial food web. However, this may have contributed to their demise if they were exposed to elevated concentrations of H2S derived from the anaerobic oxidation of methane.

scholarly journals Late Cretaceous non-marine turtles of Asia: a review of taxonomic diversity and paleobiogeography

2015 ◽  
Author(s):  
Igor Danilov ◽  
Ekaterina Obraztsova ◽  
Vladimir Sukhanov
Keyword(s):  
Late Cretaceous ◽  
Environmental Conditions ◽  
Geographical Area ◽  
Temporal Distribution ◽  
Taxonomic Diversity ◽  
Coastal Areas ◽  
Marine Turtle ◽  
Marine Turtles ◽  
Middle Asia ◽  
Different Ages

Background. This report reviews data on taxonomic diversity and paleobiogeography of Late Cretaceous (K2) non-marine turtles of Asia accumulated since latest reviews in 2000s. K2 non-marine turtles of Asia are known from four main geographical areas: Middle Asia-Kazakhstan (MAK), Mongolia (MO), China (CH) and Japan (JA). Methods. We critically reviewed composition of non-marine turtle assemblages of the K2 for each of the mentioned geographical area to make estimates of taxonomic diversity for different ages of the K2. Based on these data we analyzed temporal distribution of taxa of non-marine turtles and change in taxonomic diversity of turtle assemblages. Results. K2 turtles of MAK are represented by eight suprageneric taxa – Adocidae (Ad), Carettochelyidae (Ca), Lindholmemydidae (Li), Macrobaenidae (Ma), Nanhsiungchelyidae (Na), Trionychidae (Tr), Eucryptodira indet. (Eu), and Testudines indet. (Te), of which Ad, Li, Ma and Tr are known from the Cenomanian(CE) – early Campanian(CA), whereas other taxa only from the CE-early Turonian(TU). Taxonomic diversity changes from 10–12 species and genera, 6–8 suprageneric taxa in the CE to 7 species and genera, 4 families in the late TU early CA. K2 turtles of MO are represented by seven suprageneric taxa – Ad, Ca, Li, Ma, Meiolaniformes (Me), Na, and Tr, of which Li, Na and Tr are known from the CE-Maastrichtian(MA), Ad, Ca, and Ma, from the CE-Santonian(SA), and Me, only from the MA. Taxonomic diversity changes from 12 species, 10 genera, 6 families in the CE – SA, 8–9 species, 7–9 genera, 3 families in the CA, and 9 species, 7–8 genera, and 4 suprageneric taxa in the MA. K2 turtles of CH are represented by three suprageneric taxa (Li, Na, and Tr), but their precise temporal distribution is poorly known. Taxonomic diversity in the K2 is 12 species, 11–12 genera, and 3 families. K2 turtles of JA are represented by six suprageneric taxa (Ad, Ca, Na, Tr, Eu, and Te), of which Na are known from the CE-SA, Tr from the Coniacian(CO)-CA, and other taxa from the CO-SA. Taxonomic diversity changes from 1 species, genus, and family in the CE-TU to 7 species and genera, and 5–6 suprageneric taxa in the CO-SA. Discussion. In MAK, most significant transformation of turtle assemblages occurred in the CE-TU, whereas transformation in the SA-CA was less significant. On the contrary, in MO, most significant transformation occurred in the SA-CA, and less significant in the CA-MA.The patterns of transformation of the K2 turtle assemblages of CH and JA are not clear. The differences in the patterns of diversity and transformations of the K2 turtle assemblages in different geographical areas of Asia may be explained by different environmental conditions in these areas at that time and influence of such factors as transgressions in coastal areas (MAK and JA) and cooling and aridizations in inland areas (MO and CH).

scholarly journals Evidence for the Cretaceous sharkCretoxyrhina mantellifeeding on the pterosaurPteranodonfrom the Niobrara Formation

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e6031 ◽  
Author(s):  
David W.E. Hone ◽  
Mark P. Witton ◽  
Michael B. Habib
Keyword(s):  
North America ◽  
Late Cretaceous ◽  
Fossil Record ◽  
Cervical Vertebra ◽  
Western Interior Seaway ◽  
Niobrara Formation ◽  
Intimate Association

A cervical vertebra of the large, pelagic pterodactyloid pterosaurPteranodonsp. from the Late Cretaceous Niobrara Formation of Kansas, USA is significant for its association with a tooth from the large lamniform shark,Cretoxyrhina mantelli. Though the tooth does not pierce the vertebral periosteum, the intimate association of the fossils—in which the tooth is wedged below the left prezygapophysis—suggests their preservation together was not mere chance, and the specimen is evidence ofCretoxyrhinabitingPteranodon. It is not possible to infer whether the bite reflects predatory or scavenging behaviour from the preserved material. There are several records ofPteranodonhaving been consumed by other fish, including other sharks (specifically, the anacoracidSqualicorax kaupi), and multiple records ofCretoxyrhinabiting other vertebrates of the Western Interior Seaway, but until now interactions betweenCretoxyrhinaandPteranodonhave remained elusive. The specimen increases the known interactions between large, pelagic, vertebrate carnivores of the Western Interior Seaway of North America during the Late Cretaceous, in addition to bolstering the relatively small fossil record representing pterosaurian interactions with other species.

The oldest occurrence of brachylophosaurin hadrosaurids in Canada

2021 ◽  
pp. 1-12
Author(s):  
Michael G.W. Thompson ◽  
Fern V. Bedek ◽  
Claudia Schröder-Adams ◽  
David C. Evans ◽  
Michael J. Ryan
Keyword(s):  
Sea Level ◽  
Sea Level Change ◽  
Distinct Pattern ◽  
Environmental Response ◽  
Western Interior Seaway ◽  
Level Change ◽  
Underlying Factor ◽  
Dinosaur Park Formation ◽  
Lower Campanian ◽  
Upper Campanian

Hadrosaurids are a diverse and widely distributed group of ornithischian dinosaurs that are particularly well represented in the upper Campanian Dinosaur Park Formation of the Belly River Group of Alberta. However, the origin of this hadrosaurid diversity in Alberta is poorly understood, as the lower Campanian terrestrial deposits of the underlying Oldman and Foremost formations of the group have produced comparatively few body fossils. Here we provide the first description of a partially articulated hadrosaurid and hadrosaurid material from a bonebed from the Foremost Formation and refer it to the brachylophosaurin Probrachylophosaurus sp. indet. The material represents the oldest occurrence of Brachylophosaurini in Alberta and the oldest known hadrosaurid diagnostic to the genus level from Canada. In Alberta, Hadrosaurinae display a distinct pattern of replacement with the tribes Brachylophosaurini and Kritosaurini being confined to the lower to middle Campanian strata (below the marine Bearpaw Formation) and replaced above the Bearpaw Formation by members of Saurolophini (Prosaurolophus, Saurolophus) and Edmontosaurini (Edmontosaurus), with the latter clade persisting to the end of the Maastrichtian. Although the worldwide stratigraphic distribution of the Hadrosaurinae is complex, this pattern generally holds true for northern Laramidian hadrosaurine tribes, suggesting that their pattern of evolution and replacement may be driven by some common underlying factor such as an environmental response to fluctuations in the margins of the Western Interior Seaway due to sea level change.

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