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Bone Spring Limestone
The Bone Spring Formation is a geologic formation found in the Delaware Basin in Texas and New Mexico. It preserves fossils dating back to the Leonardian Age of the Permian Period. Description The formation consists of dark gray deep marine limestone interbedded with shale and sandstone interpreted as turbidites. The total thickness is about . The base of the formation is largely concealed in the subsurface, and the formation is overlain by the Cutoff Shale. The formation grades laterally into the Victorio Peak Formation. The uppermost shale beds of the formation have been assigned to the Avalon Shale. Fossils The formation contains fossils of the brachiopods ''Productus leonardensis'', '' Marginifera cristobalensis'', '' Pugnoides texanus'', ''P. bidentatus'', and '' Composita mexicana''; the ammonites '' Peritrochia erebus'', '' Paracelites elegans'', ''Agathiceras texanum'', and ''Perrinites''. History of investigation The formation was first designated the Bone Springs L ... [...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 (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] |
Turbidite
A turbidite is the geologic deposit of a turbidity current, which is a type of amalgamation of fluidal and sediment gravity flow responsible for distributing vast amounts of clastic sediment into the deep ocean. Sequencing Turbidites were first properly described by Arnold H. Bouma (1962), who studied deepwater sediments and recognized particular "fining-up intervals" within deep water, fine-grained shales, which were anomalous because they started at pebble conglomerates and terminated in shales. This was anomalous because within the deep ocean it had historically been assumed that there was no mechanism by which tractional flow could carry and deposit coarse-grained sediments into the abyssal depths. Bouma cycles begin with an erosional contact of a coarse lower bed of pebble to granule conglomerate in a sandy matrix, and grade up through coarse then medium plane parallel sandstone; through cross-bedded sandstone; rippled cross-bedded sand/silty sand, and finally lami ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Fossiliferous Stratigraphic Units In New Mexico
This article contains a list of fossil-bearing stratigraphic units in the state of New Mexico, U.S. Sites See also * Paleontology in New Mexico References * {{DEFAULTSORT:Fossiliferous stratigraphic units in New Mexico New Mexico Stratigraphic units A stratigraphic unit is a volume of Rock (geology), rock of identifiable origin and relative age range that is defined by the distinctive and dominant, easily mapped and recognizable petrology, petrographic, lithology, lithologic or paleontology, p ... Stratigraphy of New Mexico New Mexico geography-related lists United States geology-related lists ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petroleum Reservoir
A petroleum reservoir or oil and gas reservoir is a subsurface accumulation of hydrocarbons contained in porous or fractured rock formations. Such reservoirs form when kerogen (ancient plant matter) is created in surrounding rock by the presence of high heat and pressure in the Earth's crust. Petroleum reservoirs are broadly classified as ''conventional'' and '' unconventional'' reservoirs. In conventional reservoirs, the naturally occurring hydrocarbons, such as crude oil or natural gas, are trapped by overlying rock formations with lower permeability, while in unconventional reservoirs, the rocks have high porosity and low permeability, which keeps the hydrocarbons trapped in place, therefore not requiring a cap rock. Reservoirs are found using hydrocarbon exploration methods. Oil field An oil field is an area of accumulation of liquid oil underground in multiple (potentially linked) reservoirs, trapped as it rises by impermeable rock formations. In industrial terms, an o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perrinites
Perrinitinae is one of two subfamilies of the Perrinitidae family. They are an extinct group of ammonoid, which are shelled cephalopods related to squids, belemnite Belemnitida (or the belemnite) is an extinct order of squid-like cephalopods that existed from the Late Triassic to Late Cretaceous. Unlike squid, belemnites had an internal skeleton that made up the cone. The parts are, from the arms-most to ...s, octopuses, and cuttlefish, and more distantly to the nautiloids. References The Paleobiology Database accessed on 10/01/07 Shumarditaceae Prehistoric animal subfamilies {{Goniatitida-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agathiceras
''Agathiceras'' is a subglobose goniatitid from the family Agathiceratidae, widespread and locally abundant in Lower Pennsylvanian to Middle Permian sediments, e.g. the Urals, Sicily, and Texas. ''Agathiceras'', named by Gemmellaro in 1887 from the Middle Permian Sicilian species, '' A. suessi'', has a broadly rounded outer edge, known as the venter, being at the lower side of the animal during life, and a deeply impressed innerside, the dorsum which corresponds with the back or dorsal side of the animal. The sutures are goniatitic with three lateral and one dorsolateral lobes on either side. Those that are external are spatulate, those hidden are V-shaped. The siphuncle is primitive with the septal necks pointing to the rear, a condition known as retrosiphonate. ''Agathiceras'' is thought to be derived from ''Proshumardites'' according to Saunders ''et al''. (1999), which is thought to be derived from ''Dombarites''; all of which are included in the Agathiceratidae. ''Dombar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peritrochia
Peritrochia is an extinct genus of ammonite belonging to the order Goniatitida and family Vidrioceratidae. Specimens have been recovered from Permian beds in North America and East Timor East Timor (), also known as Timor-Leste (), officially the Democratic Republic of Timor-Leste, is an island country in Southeast Asia. It comprises the eastern half of the island of Timor, the exclave of Oecusse on the island's north-weste .... References Goniatitida {{Goniatitida-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonite
Ammonoids are a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda. These molluscs, commonly referred to as ammonites, are more closely related to living coleoids (i.e., octopuses, squid and cuttlefish) than they are to shelled nautiloids such as the living ''Nautilus'' species. The earliest ammonites appeared during the Devonian, with the last species vanishing during the Cretaceous–Paleogene extinction event. Ammonites are excellent index fossils, and linking the rock layer in which a particular species or genus is found to specific geologic time periods is often possible. Their fossil shells usually take the form of planispirals, although some helically spiraled and nonspiraled forms (known as heteromorphs) have been found. The name "ammonite", from which the scientific term is derived, was inspired by the spiral shape of their fossilized shells, which somewhat resemble tightly coiled rams' horns. Pliny the Elder ( 79 AD near Pomp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Composita Mexicana
''Composita'' is an extinct brachiopod genus that lived from the Late Devonian to the Late Permian.''Composita'' at .org ''Composita'' had a cosmopolitan global distribution, having lived on every except . [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marginifera
''Marginifera'' is an extinct genus of brachiopod belonging to the order Productida. Specimens have been found in Carboniferous to Triassic The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period ... beds in Asia, Europe, Madagascar, and North America. Species *''M. altimontana'' Sestini 1965 *''M. andreai'' Angiolini 1995 *''M. bicostala'' Lee and Gu 1980 *''M. brevisulcata'' Cooper 1957 *''M. carniolica'' Schellwien 1900 *''M. costellata'' Cooper 1957 *''M. elongatoides'' Zeng et al. 1995 *''M. ganota'' Grant 1993 *''M. gobiensis'' Chao 1927 *''M. haydenensis'' Girty 1903 *''M. hubeiensis'' Ni 1977 *''M. involuta'' Tschernyschew 1902 *''M. jalaidensis'' Lee and Gu 1980 *''M. juresanensis'' Tschernyschew 1902 *''M. lebedevi'' Tschernyschew 1902 *''M. longispina'' Sowerby 1814 *''M. mad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
