Stratigraphic range: Albian
|Unit of||Rolling Downs Group|
|Thickness||Up to 65 m (213 ft)|
The Toolebuc Formation is a geological formation that extends from Queensland across South Australia and the Northern Territory in Australia, whose strata date back to the Albian stage of the Early Cretaceous. Dinosaurs,pterosaurs, plesiosaurs, ichthyosaurs, protostegid turtles, sharks, chimaeroids and bony fish remains are among the fossils that have been recovered from the formation.
Deposition occurred in a cool to temperate inland sea setting and the present lithology is dominantly made up of limey shales with abundant Inoceramus bivalve shells. Ichthyosaurs and protostegid turtles were the most common marine reptiles at this time in the Eromanga Sea, in contrast to older Aptian deposits such as the Bulldog Shale of South Australia, which show that plesiosaurs were previously more abundant and also more diverse. The Toolebuc Formation is one of the richest known sources of Mesozoic vertebrate fossils in Australia, with notable collecting areas situated around the towns of Richmond, Julia Creek, Hughenden and Boulia.
Possible indeterminate ankylosaurid remains are present in Queensland, Australia.Indeterminate ornithopod remains have also been found in Queensland, Australia.
|Dinosaurs (including birds)|
|Nanantius||N. eos||Queensland||"Tibiotarsi and vertebra"|
|Polycotylidae indet.||Undescribed polycotylid (specimen QM F18041, nicknamed Penny)||Queensland||[ citation needed ]|
The Oxford Clay is a Jurassic marine sedimentary rock formation underlying much of southeast England, from as far west as Dorset and as far north as Yorkshire. The Oxford Clay Formation dates to the Jurassic, specifically, the Callovian and Oxfordian ages, and comprises two main facies. The lower facies comprises the Peterborough Member, a fossiliferous organic-rich mudstone. This facies and its rocks are commonly known as lower Oxford Clay. The upper facies comprises the middle Oxford Clay, the Stewartby Member, and the upper Oxford Clay, the Weymouth Member. The upper facies is a fossil poor assemblage of calcareous mudstones.
The Kimmeridge Clay is a sedimentary deposit of fossiliferous marine clay which is of Late Jurassic to lowermost Cretaceous age and occurs in southern and eastern England and in the North Sea. This rock formation is the major source rock for North Sea oil. The fossil fauna of the Kimmeridge Clay includes turtles, crocodiles, sauropods, plesiosaurs, pliosaurs and ichthyosaurs, as well as a number of invertebrate species.
Platypterygius is an ichthyosaur of the family Ophthalmosauridae. It is most closely related to the genera Caypullisaurus and Brachypterygius. The ichthyosaur lived from the Early Cretaceous (Hauterivian) to the earliest Late Cretaceous (Cenomanian) and had a cosmopolitan distribution.
The Bearpaw Formation, also called the Bearpaw Shale, is a geologic formation of Late Cretaceous (Campanian) age. It outcrops in the U.S. state of Montana, as well as the Canadian provinces of Alberta and Saskatchewan, and was named for the Bear Paw Mountains in Montana. It includes a wide range of marine fossils, as well as the remains of a few dinosaurs. It is known for its fossil ammonites, some of which are mined in Alberta to produce the organic gemstone ammolite.
The Maevarano Formation is a Late Cretaceous sedimentary rock formation found in the Mahajanga Province of northwestern Madagascar. It is most likely Maastrichtian in age, and records a seasonal, semiarid environment with rivers that had greatly varying discharges. Notable animal fossils recovered include the theropod dinosaur Majungasaurus, the early bird Vorona, the flying dromaeosaur Rahonavis, the titanosaurian sauropod Rapetosaurus, and the giant frog Beelzebufo.
The Kota Formation is a geological formation in India. The precise age of Kota Formation are uncertain, but it dates from the Early to Middle Jurassic, and is split into a Lower Member and Upper Member. The lower member is thought to be Hettangian-Pliensbachian. While the upper unit is thought to be Toarcian, but may possibly extend into the Aalenian. It conformably overlies the Dharmaram Formation which is Late Triassic to earliest Jurassic and is unconformably overlain by the Early Cretaceous Gangapur Formation. The lower member is approximately 100 m thick while the upper member is 490 m thick. Both subunits primarily consist of mudstone and sandstone, but near the base of the upper unit there is a 20-30 metre thick succession of limestone deposited in a freshwater setting.
The La Huérguina Formation is a geological formation in Spain whose strata date back to the Barremian stage of the Early Cretaceous. Las Hoyas is a Konservat-Lagerstätte within the formation, located near the city of Cuenca, Spain. The site is mostly known for its exquisitely preserved dinosaurs, especially enantiornithines. The lithology of the formation mostly consists of lacustarine limestone deposited in a freshwater wetland environment.
The Cerro Barcino Formation is a geological formation in South America whose strata span the Early Cretaceous. The top age for the formation has been estimated to be Albian. Earlier estimates placed the formation until the Campanian.
The Allaru Formation, also known as the Allaru Mudstone, is a geological formation in Queensland, Australia, whose strata date back to the Early Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation.
The Griman Creek Formation is a geological formation in northern New South Wales and southern Queensland, Australia whose strata date back to the Cenomanian of the Late Cretaceous. It is most notable for its fossils, including those of dinosaurs and primitive montremes, as well as being a major source of opal, both of which are found near Lightning Ridge, New South Wales
The Aguja Formation is a geological formation in North America, exposed in Texas, United States and Chihuahua and Coahuila in Mexico, whose strata date back to the Late Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation.
The Bissekty Formation is a geologic formation and Lagerstätte which crops out in the Kyzyl Kum desert of Uzbekistan, and dates to the Late Cretaceous Period. Laid down in the mid to late Turonian, it is dated to about 92 to 90 Ma.
During the time of the deposition of the Niobrara Chalk, much life inhabited the seas of the Western Interior Seaway. By this time in the Late Cretaceous many new lifeforms appeared such as mosasaurs, which were to be some of the last of the aquatic lifeforms to evolve before the end of the Mesozoic. Life of the Niobrara Chalk is comparable to that of the Dakota Formation, although the Dakota Formation, which was deposited during the Cenomanian, predates the chalk by about 10 million years.
The Birdrong Sandstone is an Early Cretaceous geologic formation of the Barrow Group in Western Australia. Dinosaur remains are among the fossils that have been recovered from the formation, although none have yet been referred to a specific genus.
The Miria Formation is a Late Cretaceous geologic formation. Possible indeterminate theropod remains have been recovered from it, as well as those of sea turtles, and possible azhdarchid pterosaurs. The lithology of the unit consists of calcarenite with abundant phosphatic nodules.
The Uberaba Formation is a Campanian geologic formation belonging to the Bauru Group of the Bauru Sub-basin, Paraná Basin located in Minas Gerais state of southeastern Brazil. The Uberaba Formation, intercalating the fossiliferous older Adamantina and younger Marília Formation, comprises limestones, sandstones, and conglomerates, often cemented by calcite with volcaniclastic sediments. The formation interfingers with the Adamantina Formation.
The Whitby Mudstone is a Toarcian geological formation in Yorkshire and Worcestershire, England. The formation, part of the Lias Group, is present in the Cleveland and Worcester Basins and the East Midlands Shelf.
The prehistory of the United States comprises the occurrences within regions now part of the United States of America during the interval of time spanning from the formation of the Earth to the documentation of local history in written form. At the start of the Paleozoic era, what is now "North" America was actually in the southern hemisphere. Marine life flourished in the country's many seas, although terrestrial life had not yet evolved. During the latter part of the Paleozoic, seas were largely replaced by swamps home to amphibians and early reptiles. When the continents had assembled into Pangaea drier conditions prevailed. The evolutionary precursors to mammals dominated the country until a mass extinction event ended their reign.
Leyvachelys is an extinct genus of turtles in the family Sandownidae from the Early Cretaceous of the present-day Altiplano Cundiboyacense, Eastern Ranges, Colombian Andes. The genus is known only from its type species, Leyvachelys cipadi, described in 2015 by Colombian paleontologist Edwin Cadena. Fossils of Leyvachelys have been found in the fossiliferous Paja Formation, close to Villa de Leyva, Boyacá, after which the genus is named. The holotype specimen is the oldest and most complete sandownid turtle found to date.
The Bulldog Shale is a formation of Early Cretaceous age that forms part of the Marree Subgroup of the Rolling Downs Group, located in the Eromanga Basin of South Australia, Queensland and New South Wales.