Herpetofauna of the Calf Creek Local Fauna (Lower Oligocene: Cypress Hills Formation) of Saskatchewan

1972 ◽  
Vol 9 (12) ◽  
pp. 1612-1631 ◽  
Author(s):  
J. Alan Holman
Keyword(s):  
Middle Eocene ◽  
Tropical Climate ◽  
Local Fauna ◽  
Lower Oligocene ◽  
Bridger Formation

A Lower Oligocene deposit, the Calf Creek local fauna of the Cypress Hills Formation, near Eastend, Saskatchewan, yielded the remains of one salamander, three anurans, three turtles, a crocodilian, six lizards, and three snakes. All of the 13 herpetological families identified are extant. The four amphibian genera identified are extant, but only two of nine reptilian genera identified are living today. One genus and species and one species of iguanid lizard, one species of xantusiid lizard, and one species of small boid snake are described as new. The Calf Creek local fauna herpetofauna indicates a subtropical or tropical climate. The herpetofauna of the Calf Creek local fauna shows several differences from the herpetofauna of the Middle Eocene Tabernacle Butte local fauna of the Bridger Formation of Wyoming.

Paleontology and stratigraphy of Middle Eocene rock units in the southern Green River and Uinta Basins, Wyoming and Utah

2017 ◽  
Vol 4 ◽  
pp. 1-53 ◽  
Author(s):  
Paul Murphey ◽  
K.E. Townsend ◽  
Anthony Friscia ◽  
James Westgate ◽  
Emmett Evanoff ◽  
...  
Keyword(s):  
Current Knowledge ◽  
Middle Eocene ◽  
Green River Basin ◽  
Green River ◽  
Scientific Exploration ◽  
History Of ◽  
Climatic History ◽  
Field Excursion ◽  
Land Mammal ◽  
Bridger Formation

The Bridger Formation is restricted to the Green River Basin in southwest Wyoming, and the Uinta and Duchesne River Formations are located in the Uinta Basin in Utah. These three rock units and their diverse fossil assemblages are of great scientific importance and historic interest to vertebrate paleontologists. Notably, they are also the stratotypes from oldest to youngest for the three middle Eocene North American Land Mammal Ages—the Bridgerian, Uintan, and Duchesnean. The fossils and sediments of these formations provide a critically important record of biotic, environmental, and climatic history spanning approximately 10 million years (49 to 39 Ma). This article provides a detailed field excursion through portions of the Green River and Uinta Basins that focuses on locations of geologic, paleontologic, and historical interest. In support of the field excursion, we also provide a review of current knowledge of these formations with emphasis on lithostratigraphy, biochronology, depositional, and paleoenvironmental history, and the history of scientific exploration.

An Early Oligocene age for the oldest known monkeys and rodents of South America

2021 ◽  
Vol 118 (37) ◽  
pp. e2105956118
Author(s):  
Kenneth E. Campbell ◽  
Paul B. O’Sullivan ◽  
John G. Fleagle ◽  
Dorien de Vries ◽  
Erik R. Seiffert
Keyword(s):  
South America ◽  
Amazon Basin ◽  
Middle Eocene ◽  
Detrital Zircons ◽  
Age Difference ◽  
Early Oligocene ◽  
Lower Oligocene ◽  
Upper Oligocene ◽  
Caviomorph Rodents ◽  
Age Estimates

The Santa Rosa fossil locality in eastern Perú produced the first Paleogene vertebrate fauna from the Amazon Basin, including the oldest known monkeys from South America. This diverse paleofauna was originally assigned an Eocene age based largely on the stage of evolution of the site’s caviomorph rodents and marsupials. Here, we present detrital zircon dates that indicate that the maximum composite age of Santa Rosa is 29.6 ± 0.08 Ma (Lower Oligocene), although several zircons from Santa Rosa date to the Upper Oligocene. The first appearance datum for Caviomorpha in South America is purported to be the CTA-27 site in the Contamana region of Perú, which is hypothesized to be ∼41 Ma (Middle Eocene) in age. However, the presence of the same caviomorph species and/or genera at both CTA-27 and at Santa Rosa is now difficult to reconcile with a >11-My age difference. To further test the Middle Eocene age estimate for CTA-27, we ran multiple Bayesian tip-dating analyses of Caviomorpha, treating the ages of all Paleogene species from Perú as unknown. These analyses produced mean age estimates for Santa Rosa that closely approximate the maximum 29.6 ± 0.08 Ma composite date provided by detrital zircons, but predict that CTA-27 is much younger than currently thought (∼30 Ma). We conclude that the ∼41 Ma age proposed for CTA-27 is incorrect, and that there are currently no compelling Eocene records of either rodents or primates in the known fossil record of South America.

scholarly journals Paleontology and stratigraphy of Middle Eocene rock units in the southern Green River and Uinta Basins, Wyoming and Utah

2017 ◽  
Vol 4 ◽  
pp. 1-53 ◽  
Author(s):  
Paul C. Murphey ◽  
K.E. Beth Townsend ◽  
Anthony R. Friscia ◽  
James Westgate ◽  
Emmett Evanoff ◽  
...  
Keyword(s):  
Current Knowledge ◽  
Middle Eocene ◽  
Green River Basin ◽  
Green River ◽  
Scientific Exploration ◽  
History Of ◽  
Climatic History ◽  
Field Excursion ◽  
Land Mammal ◽  
Bridger Formation

The Bridger Formation is restricted to the Green River Basin in southwest Wyoming, and the Uinta and Duchesne River Formations are located in the Uinta Basin in Utah. These three rock units and their diverse fossil assemblages are of great scientific importance and historic interest to vertebrate paleontologists. Notably, they are also the stratotypes from oldest to youngest for the three middle Eocene North American Land Mammal Ages—the Bridgerian, Uintan, and Duchesnean. The fossils and sediments of these formations provide a critically important record of biotic, environmental, and climatic history spanning approximately 10 million years (49 to 39 Ma). This article provides a detailed field excursion through portions of the Green River and Uinta Basins that focuses on locations of geologic, paleontologic, and historical interest. In support of the field excursion, we also provide a review of current knowledge of these formations with emphasis on lithostratigraphy, biochronology, depositional, and paleoenvironmental history, and the history of scientific exploration.

scholarly journals A crocodilian coprolite from the lower Oligocene Viborg Formation of Sofienlund Lergrav, Denmark

2018 ◽  
Vol 66 ◽  
pp. 181-187
Author(s):  
Jesper Milàn ◽  
Erik Skovbjerg Rasmussen ◽  
Karen Dybkjær
Keyword(s):  
Middle Eocene ◽  
Marine Clay ◽  
Dinoflagellate Cyst ◽  
Vertebrate Fauna ◽  
Lower Oligocene ◽  
Homogeneous Core ◽  
Important Addition ◽  
Size And Morphology ◽  
Warm Temperate

A large, well-preserved vertebrate coprolite found in the clay pit Sofienlund Lergrav, Jylland, is identified as crocodilian due to its size and morphology. The coprolite consists of several concentric layers wrapped around a more homogeneous core. Weak constriction marks are present on the surface. Dinoflagellate cyst contents of the coprolite indicate a mid-Lutetian to earliest Rupelian (middle Eocene to earliest Oligocene) age, which at Sofienlund Lergrav places it within the lower Oligocene Viborg Formation. The coprolite can thus be dated as approximately 33–34 Ma old. The Viborg Formation in Denmark represents a period with deposition of hemipelagic marine clay and formation of glaucony. The nearest shoreline was located c. 200 km north of the location of the present day Sofienlund Lergrav, and the climate was humid, warm-temperate to sub-tropical. The presence of a crocodilian coprolite is an important addition to the sparse Oligocene vertebrate fauna of Denmark, which previously only consisted of sharks and cetaceans.

scholarly journals PALAEOGRAPHIC EVOLUTION OF PINDOS BASIN DURING PALEOGENE USING CALCAREOUS NANNOFOSSILS

2018 ◽  
Vol 36 (2) ◽  
pp. 836 ◽  
Author(s):  
G. Ananiadis ◽  
I. Vakalas ◽  
A. Zelilidis ◽  
K. Stoykova
Keyword(s):  
Middle Eocene ◽  
Foreland Basin ◽  
Submarine Canyon ◽  
Basin Evolution ◽  
Calcareous Nannofossils ◽  
Upper Eocene ◽  
Subaerial Exposure ◽  
Early Oligocene ◽  
Lower Oligocene ◽  
Piggyback Basin

A different basin evolution is suggested between the northern and southern parts of the Pindos basin, based on biostratigraphic dating results. Characteristic nannofossils showed that flysch sedimentation in the whole basin started in the Paleocene and generally finished during the Eocene, with the exception of the Konitsa and Milia areas where sedimentation lasted until Early Oligocene. Although, basin depth increased southwards, Kastaniotikos and Sperchios faults affected the geometry of Pindos basin, creating ridges and troughs within the basin. Due to this segmentation of the basin, the continuity of the sedimentation in the northern part of the study area until Oligocene is suggested. Calcareous nannofossils recovered from this northern part indicate a Paleocene NP5 to early Cligocene (NP20-21) age. On the other hand, in the southern part, sedimentation of flysch was lasted until middle Eocene. According this model, sedimentation in the southern part, stopped during the middle Eocene, was followed by subaerial exposure and the migration of clastic sedimentation to the western part of Pindos zones (Pindos foreland basin of Ionian zone). At this time, in the northern part, a small-restricted basin was continuously active as a piggyback basin from upper Eocene to lower Oligocene and shallow deposits (slope and submarine canyon deposits, delta fan deposits) accumulated.

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