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Baldy Hill Formation
The Baldy Hill Formation is a geologic formation in northeastern New Mexico and western Oklahoma. It preserves fossils dating back to the late Triassic period. Description The Baldy Hill Formation is a dark purple, reddish brown, or greenish gray silty to sandy mudstone with some fine-grained sandstone. Its base is not exposed at the type section, but it is at least . It is overlain by the Travesser Formation, with the contact marked by the Cobert Canyon Sandstone Bed, a persistent layer of conglomerate beds now assigned to the Baldy Hill Formation or possibly the overlying Travesser Formation (which in turn is sometimes regarded as equivalent to the Chinle Formation.) The formation may correlate with either the Garita Creek Formation or the Los Esteros Member of the Santa Rosa Formation. Fossils Fossils of amphibians and phytosaurs of Carnian to Norian age have been found in the Cobert Canyon Sandstone. History of investigation The formation was first named by Baldwin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formation (stratigraphy)
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 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 Abraham Gottlob W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Contact (geology)
A geological contact is a boundary which separates one rock body from another. A contact can be formed during deposition, by the intrusion of magma, or through faulting or other deformation of rock beds that brings distinct rock bodies into contact. The geologic subdiscipline of stratigraphy is primarily concerned with depositional contacts,Boggs 2006, p. 401 while faults and shear zones are of particular interest in structural geology. Faults and shear zones can be regarded as a form of secondary structure in the rock beds.Davis and Kluth 2011, p.21 Types of contacts Depositional Conformable Conformable contacts represent no time gap in the geologic record. They are usually planar, though they may have slightly irregular topography. These contacts represent continual, uninterrupted deposition and accumulation of sedimentary rocks, or represent lava flows. A conformable contact can be ''abrupt'', where the contact separates beds of distinct lithology. Abrupt contacts co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleontology In Oklahoma
Paleontology in Oklahoma refers to paleontological research occurring within or conducted by people from the U.S. state of Oklahoma. Oklahoma has a rich fossil record spanning all three eras of the Phanerozoic Eon. Oklahoma is the best source of Pennsylvanian fossils in the United States due to having an exceptionally complete geologic record of the epoch. From the Cambrian to the Devonian, all of Oklahoma was covered by a sea that would come to be home to creatures like brachiopods, bryozoans, graptolites and trilobites. During the Carboniferous, an expanse of coastal deltaic swamps formed in areas of the state where early tetrapods would leave behind footprints that would later fossilize. The sea withdrew altogether during the Permian period. Oklahoma was home a variety of insects as well as early amphibians and reptiles. Oklahoma stayed dry for most of the Mesozoic. During the Late Triassic, carnivorous dinosaurs left behind footprints that would later fossilize. During the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Fossiliferous Stratigraphic Units In Oklahoma
This article contains a list of fossil-bearing stratigraphic units in the state of Oklahoma, U.S. Sites See also * Paleontology in Oklahoma References * List of Formations in the National Geologic Map Database {{DEFAULTSORT:Fossiliferous stratigraphic units in Oklahoma Oklahoma Stratigraphic units Stratigraphy of Oklahoma Oklahoma geography-related lists United States geology-related lists ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cimarron River (Arkansas River Tributary)
The Cimarron River ( ; iow, Ñíxgu, script=Latn or , meaning 'Salt River'; chy, Hotóao'hé'e) extends across New Mexico, Oklahoma, Colorado, and Kansas. The headwaters flow from Johnson Mesa west of Folsom in northeastern New Mexico. Much of the river's length lies in Oklahoma, where it either borders or passes through eleven counties. There are no major cities along its route. The river enters the Oklahoma Panhandle near Kenton, Oklahoma, crosses the southeastern corner of Colorado into Kansas, reenters the Oklahoma Panhandle, reenters Kansas, and finally returns to Oklahoma where it joins the Arkansas River at Keystone Reservoir west of Tulsa, Oklahoma, its only impoundment. The Cimarron drains a basin that encompasses about .Larry O'Dell, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Norian
The Norian is a division of the Triassic Period. It has the rank of an age ( geochronology) or stage (chronostratigraphy). It lasted from ~227 to million years ago. It was preceded by the Carnian and succeeded by the Rhaetian. Stratigraphic definitions The Norian was named after the Noric Alps in Austria. The stage was introduced into scientific literature by Austrian geologist Edmund Mojsisovics von Mojsvar in 1869. The Norian Stage begins at the base of the ammonite biozones of '' Klamathites macrolobatus'' and '' Stikinoceras kerri'', and at the base of the conodont biozones of '' Metapolygnathus communisti'' and '' Metapolygnathus primitius''. A global reference profile for the base (a GSSP) had in 2009 not yet been appointed. The top of the Norian (the base of the Rhaetian) is at the first appearance of ammonite species '' Cochloceras amoenum''. The base of the Rheatian is also close to the first appearance of conodont species '' Misikella spp.'' and '' Epigondolell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carnian
The Carnian (less commonly, Karnian) is the lowermost stage of the Upper Triassic Series (or earliest age of the Late Triassic Epoch). It lasted from 237 to 227 million years ago (Ma). The Carnian is preceded by the Ladinian and is followed by the Norian. Its boundaries are not characterized by major extinctions or biotic turnovers, but a climatic event (known as the Carnian pluvial episode characterized by substantial rainfall) occurred during the Carnian and seems to be associated with important extinctions or biotic radiations. Stratigraphic definitions The Carnian was named in 1869 by Mojsisovics. It is unclear if it was named after the Carnic Alps or after the Austrian region of Carinthia (''Kärnten'' in German) or after the Carnia historical region in northwestern Italy. The name, however, was first used referring to a part of the Hallstatt Limestone cropping out in Austria. The base of the Carnian Stage is defined as the place in the stratigraphic record ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytosaurs
Phytosaurs (Φυτόσαυροι in greek) are an extinct group of large, mostly semiaquatic Late Triassic archosauriform reptiles. Phytosaurs belong to the order Phytosauria. Phytosauria and Phytosauridae are often considered to be equivalent groupings containing the same species, but some studies have identified non-phytosaurid phytosaurians. Phytosaurs were long-snouted and heavily armoured, bearing a remarkable resemblance to modern crocodilians in size, appearance, and lifestyle, as an example of convergence or parallel evolution. The name "phytosaur" means "plant reptile", as the first fossils of phytosaurs were mistakenly thought to belong to plant eaters. The name is misleading because the sharp teeth in phytosaur jaws clearly show that they were predators. For many years, phytosaurs were considered to be the most basal group of Pseudosuchia (crocodile-line archosaurs), meaning that they were thought to be more closely related to the crocodilians than to birds (the oth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphibians
Amphibians are four-limbed and ectothermic vertebrates of the class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terrestrial, fossorial, arboreal or freshwater aquatic ecosystems. Thus amphibians typically start out as larvae living in water, but some species have developed behavioural adaptations to bypass this. The young generally undergo metamorphosis from larva with gills to an adult air-breathing form with lungs. Amphibians use their skin as a secondary respiratory surface and some small terrestrial salamanders and frogs lack lungs and rely entirely on their skin. They are superficially similar to reptiles like lizards but, along with mammals and birds, reptiles are amniotes and do not require water bodies in which to breed. With their complex reproductive needs and permeable skins, amphibians are often ecological indicators; in recent decades there has been a dramati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Santa Rosa Formation, New Mexico
The Santa Rosa Formation is a geologic formation exposed in New Mexico that was deposited in the Carnian Age of the late Triassic Period. Description The formation consists mostly of white to brown sandstone and mudstone with some interbedded conglomerate. The formation lies on the Anton Chico Formation and is overlain by the Garita Creek Formation. The total thickness of the formation is . The formation is divided into (in ascending stratigraphic order) the ''Tecolotito Member'', which is primarily sandstone; the ''Los Esteros Member'', which is primarily mudstone; and the ''Tres Lagunas Member'', which is primarily sandstone. The sandstone members are interpreted as alluvial sheets deposited by braided streams. The Los Esteros Member is interpreted as a lacustrine deposit in lakes that formed due to local subsidence from dissolution of underlying Permian salt beds. Paleocurrents were primarily to the south in the Tecolotito Member and northeast in the Tres Lagunas Member ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Garita Creek Formation
The Garita Creek Formation is a geologic Formation (geology), formation in New Mexico that contains vertebrate fossils characteristic of the Carnian Age (geology), Age of the late Triassic .Lucas and Hunt 1989 The formation may be synonymous with the Tecovas Formation in Texas.Lehman 1994 Description The formation consists mostly of gray red to red or mottled gray green mudstone containing limestone nodules. About 25% of the formation is massive fine-grained laminar gray red sandstone. It rests Contact (geology)#Conformable, conformably on the Santa Rosa Formation, New Mexico, Santa Rosa Formation, and is overlain disconformably by the Trujillo Formation. The total thickness of the formation is . It is exposed throughout the drainage of the Conchas River and its tributaries west to the Sangre de Cristo Mountains.Lucas ''et al.'' 1990 Fossils The formation contains vertebrate fossils of ''Desmatosuchus'', ''Typothorax'', ''Paratypothorax'', ''Postosuchus'', rauisuchians, Metopos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Correlation (geology)
Biostratigraphy is the branch of stratigraphy which focuses on correlating and assigning relative ages of rock strata by using the fossil assemblages contained within them.Hine, Robert. “Biostratigraphy.” ''Oxford Reference: Dictionary of Biology'', 8th ed., Oxford University Press, 2019. The primary objective of biostratigraphy is ''correlation'', demonstrating that a particular horizon in one geological section represents the same period of time as another horizon at a different section. Fossils within these strata are useful because sediments of the same age can look completely different, due to local variations in the sedimentary environment. For example, one section might have been made up of clays and marls, while another has more chalky limestones. However, if the fossil species recorded are similar, the two sediments are likely to have been laid down around the same time. Ideally these fossils are used to help identify biozones, as they make up the basic biostratigrap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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