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Los Blanquitos Formation
The Los Blanquitos Formation is a geological formation in Salta Province, Argentina whose strata date back to the Campanian age of the Late Cretaceous Period. Dinosaur remains are among the fossils that have been recovered from the formation.Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Cretaceous, South America)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 600-604. . The formation consists of friable, micaceous, grayish-red sandstones with quartz pebbles containing small carbonate veins. In the base of this layer the remains of a titanosaurid dinosaur were discovered. Above the layer with bones appears a lens of thick, greenish-gray, calcareous, very hard sandstone with pebbles and gravel. The bones were covered by a "halo" of the same rock but of greenish or grayish color, especially visible because the normal sediment is red. The bed thickness is . [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geological Formation
A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics (lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exposed in a geographical region (the stratigraphic column). It is the fundamental unit of lithostratigraphy, the study of strata or rock layers. A formation must be large enough that it can be mapped at the surface or traced in the subsurface. Formations are otherwise not defined by the thickness (geology), thickness of their rock strata, which can vary widely. They are usually, but not universally, tabular in form. They may consist of a single lithology (rock type), or of alternating beds of two or more lithologies, or even a heterogeneous mixture of lithologies, so long as this distinguishes them from adjacent bodies of rock. The concept of a geologic formation goes back to the beginnings of modern scientific geology. The term was used by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guemesia
''Guemesia'' (named after Martín Miguel de Güemes, whose death bicentenary was in 2021) is a genus of abelisaurid dinosaur from the Late Cretaceous Los Blanquitos Formation of Salta Province, Argentina. The type and only species is ''Guemesia ochoai'', known from a nearly complete braincase. It is one of the smallest abelisaurids currently known. Discovery The holotype of ''Guemesia'', IBIGEO-P 103, is a small, nearly complete braincase. It was found in the Los Blanquitos Formation, in the Amblayo Valley of Salta Province, Argentina. The specimen was described in 2022 by Agnolín ''et al''. as belonging to a new genus and species of abelisaurid dinosaur, and the first dinosaur of its kind known from the area. Classification Agnolín ''et al.'' place ''Guemesia'' as a derived abelisaurid within the clade Brachyrostra. Paleoecology ''Guemesia'' is known from the Los Blanquitos Formation. The controversial tetanuran theropod ''Unquillosaurus'' is also known from this ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossiliferous Stratigraphic Units Of South America
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the absol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluvial Deposits
In geography and geology, fluvial processes are associated with rivers and streams and the deposits and landforms created by them. When the stream or rivers are associated with glaciers, ice sheets, or ice caps, the term glaciofluvial or fluvioglacial is used. Fluvial processes Fluvial processes include the motion of sediment and erosion or deposition on the river bed. The movement of water across the stream bed exerts a shear stress directly onto the bed. If the cohesive strength of the substrate is lower than the shear exerted, or the bed is composed of loose sediment which can be mobilized by such stresses, then the bed will be lowered purely by clearwater flow. In addition, if the river carries significant quantities of sediment, this material can act as tools to enhance wear of the bed ( abrasion). At the same time the fragments themselves are ground down, becoming smaller and more rounded ( attrition). Sediment in rivers is transported as either bedload (the coarser f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sandstone Formations
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) because they are the most resistant minerals to weathering processes at the Earth's surface. Like uncemented sand, sandstone may be any color due to impurities within the minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Since sandstone beds often form highly visible cliffs and other topographic features, certain colors of sandstone have been strongly identified with certain regions. Rock formations that are primarily composed of sandstone usually allow the percolation of water and other fluids and are porous enough to store large quantities, making them valuable aquifers and petroleum reservoirs. Quartz-bearing sandstone can be changed into quartzite through metamorphism, usually related to tec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Campanian Stage
The Campanian is the fifth of six ages of the Late Cretaceous Epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campanian spans the time from 83.6 (± 0.2) to 72.1 (± 0.2) million years ago. It is preceded by the Santonian and it is followed by the Maastrichtian. The Campanian was an age when a worldwide sea level rise covered many coastal areas. The morphology of some of these areas has been preserved: it is an unconformity beneath a cover of marine sedimentary rocks. Etymology The Campanian was introduced in scientific literature by Henri Coquand in 1857. It is named after the French village of Champagne in the department of Charente-Maritime. The original type locality was a series of outcrop near the village of Aubeterre-sur-Dronne in the same region. Definition The base of the Campanian Stage is defined as a place in the stratigraphic column where ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous Argentina
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin ''creta'', "chalk", which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation ''Kreide''. The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now- extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Earth by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Upper Cretaceous Series Of South America
Upper may refer to: * Shoe upper or ''vamp'', the part of a shoe on the top of the foot * Stimulant, drugs which induce temporary improvements in either mental or physical function or both * ''Upper'', the original film title for the 2013 found footage film ''The Upper Footage ''The Upper Footage'' (also known as ''Upper'') is a 2013 found footage film written and directed by Justin Cole. First released on January 31, 2013 to a limited run of midnight theatrical screenings at Landmark’s Sunshine Cinema in New York Cit ...'' See also {{Disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geologic Formations Of Argentina
Geology () is a branch of natural science concerned with Earth and other astronomical objects, the features or rocks of which it is composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth sciences, including hydrology, and so is treated as one major aspect of integrated Earth system science and planetary science. Geology describes the structure of the Earth on and beneath its surface, and the processes that have shaped that structure. It also provides tools to determine the relative and absolute ages of rocks found in a given location, and also to describe the histories of those rocks. By combining these tools, geologists are able to chronicle the geological history of the Earth as a whole, and also to demonstrate the age of the Earth. Geology provides the primary evidence for plate tectonics, the evolutionary history of life, and the Earth's past climates. Geologists broadly study the properties and processes of Earth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Dinosaur-bearing Rock Formations
This list of dinosaur-bearing rock formations is a list of geologic formations in which dinosaur fossils have been documented. Containing body fossils * List of stratigraphic units with dinosaur body fossils ** List of stratigraphic units with few dinosaur genera ** List of stratigraphic units with indeterminate dinosaur fossils Containing trace fossils * List of stratigraphic units with dinosaur trace fossils ** List of stratigraphic units with dinosaur tracks *** List of stratigraphic units with ornithischian tracks *** List of stratigraphic units with sauropodomorph tracks *** List of stratigraphic units with theropod tracks See also * Lists of fossiliferous stratigraphic units * List of fossil sites * Mesozoic The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Creta ... {{DE ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Titanosaurus
''Titanosaurus'' (; ) is a dubious genus of sauropod dinosaurs, first described by Richard Lydekker in 1877.R. Lydekker. (1877). Notices of new and other Vertebrata from Indian Tertiary and Secondary rocks. ''Records of the Geological Survey of India'' 10(1):30-43 It is known from the Maastrichtian (Upper Cretaceous) Lameta Formation of India. Discovery and naming ''Titanosaurus'', literally meaning 'titanic lizard', was named after the mythological Titans. ''Titanosaurus'' was the first Indian dinosaur to be named and properly described, having been recorded for the first time in 1877. The type species, ''T. indicus'', was named in 1877, and the second species, ''T. blanfordi'', was named in 1879.R. Lydekker. (1879). Fossil Reptilia and Batrachia. ''Memoirs of the Geological Survey of India. Palaeontologia Indica, Series IV. Indian Pretertiary Vertebrata'' 1(3):1-36 Both species were named by Richard Lydekker. ''T. indicus'' and ''T. blanfordi'' are 70 million years old. ''T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maniraptoran
Maniraptora is a clade of coelurosaurian dinosaurs which includes the birds and the non-avian dinosaurs that were more closely related to them than to ''Ornithomimus velox''. It contains the major subgroups Avialae, Deinonychosauria, Oviraptorosauria and Therizinosauria. ''Ornitholestes'' and the Alvarezsauroidea are also often included. Together with the next closest sister group, the Ornithomimosauria, Maniraptora comprises the more inclusive clade Maniraptoriformes. Maniraptorans first appear in the fossil record during the Jurassic Period (see ''Eshanosaurus''), and survive today as living birds. Description Maniraptorans are characterized by long arms and three-fingered hands (though reduced or fused in some lineages), as well as a "half-moon shaped" (semi-lunate) bone in the wrist (carpus). In 2004, Tom Holtz and Halszka Osmólska pointed out six other maniraptoran characters relating to specific details of the skeleton. Unlike most other saurischian dinosaurs, which have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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