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Fusselman Formation
The Fusselman Formation is a geologic formation in westernmost Texas and southern New Mexico. It preserves fossils dating back to the early Silurian period. Description The formation consists mostly of medium to dark gray massive dolomite. It has a light and dark banded appearance due to alternating beds of light gray peritidal laminated carbonate mudstone and dark gray cherty wackestone or packstone containing abundant corals. The total thickness is over in the Florida Mountains but the formation varies greatly in thickness. The formations unconformably overlies the Montoya Group and is overlain by the Onate Formation. The upper contact shows that the area was tilted and eroded prior to the Devonian. The formation is divided into the Chamberino, Flag Hill, and Crazycat members in the Sacramento Mountains. Extensive dolomitization of the formation has obscured its primary depositional fabric and made interpretation of its depositional environment difficult. Fossi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geologic 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 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 Wer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Florida Mountains
The Florida Mountains are a small long, mountain range in New Mexico. The mountains lie in southern Luna County about southeast of Deming, and north of the state of Chihuahua, Mexico; the range lies in the north of the Chihuahuan Desert region, and extreme southwestern New Mexico. The Florida Mountains are east and adjacent to New Mexico State Road 11, the north–south route to Chihuahua; it becomes Highway 23 in Chihuahua and connects to Mexican Federal Highway 2, the major east–west route of the north Chihuahuan Desert adjacent the U.S.-Mexico border. Description The Florida Mountains are a small, compact range about long, with various peaks from . The range highpoint is Florida Peak, , which lies near the north. Other high peaks in the center-south, are Gym, Baldy, and South Peak. Four other peaks are in the extreme northwest; besides Florida Peak, the tallest of the other four is Capitol Dome, at . Most of the land surrounding the prominent rise of the mountain ran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastropod
The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. There are many thousands of species of sea snails and slugs, as well as freshwater snails, freshwater limpets, and land snails and slugs. The class Gastropoda contains a vast total of named species, second only to the insects in overall number. The fossil history of this class goes back to the Late Cambrian. , 721 families of gastropods are known, of which 245 are extinct and appear only in the fossil record, while 476 are currently extant with or without a fossil record. Gastropoda (previously known as univalves and sometimes spelled "Gasteropoda") are a major part of the phylum Mollusca, and are the most highly diversified class in the phylum, with 65,000 to 80,000 living snail and slug species. The anatomy, behavior, feeding, and re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heliolites
''Heliolites'' is a large and heterogenous genus of extinct tabulate corals in the family Heliolitidae. Specimens have been found in Ordovician to Devonian beds in North America, Europe, Africa, Asia, and Australia. The genus is particularly abundant in the Wellin Member of the Hanonet Formation of Belgium. Members of the genus are distinguished by a prominent tubular coenenchyme (the tissue linking neighboring polyps) with 14–17 tubules around each corallite A corallite is the skeletal cup, formed by an individual stony coral polyp, in which the polyp sits and into which it can retract. The cup is composed of aragonite, a crystalline form of calcium carbonate, and is secreted by the polyp. Corallit ... (the stony cup in which each polyp sits.) References Tabulata Prehistoric cnidarian genera Fossil taxa described in 1846 {{coral-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halysites
''Halysites'' (meaning ''chain coral'') is an extinct genus of tabulate coral. Colonies range from less than one to tens of centimeters in diameter, and they fed upon plankton. These tabulate corals lived from the Ordovician to the Devonian (from 449.5 to 412.3 Ma). Fossils of ''Halysites'' species have been found in the sediments of North America, Europe, Asia and Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma .... Species Species in the genus ''Halysites'' include: * ''Halysites catenularia'' Linnaeus, 1767 * ''Halysites encrustans'' Buehler * ''Halysites grandis'' Sharkova, 1981 * ''Halysites infundibuliformis'' Buehler * ''Halysites junior'' Klaamann, 1961 * ''Halysites louisvillensis'' Stumm * ''Halysites meandrina'' Troost * ''Halysites magnitubus'' Buehler * ''Hal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Favosites
''Favosites'' is an extinct genus of tabulate coral characterized by polygonal closely packed corallites (giving it the common name "honeycomb coral"). The walls between corallites are pierced by pores known as mural pores which allowed transfer of nutrients between polyps. ''Favosites'', like many corals, thrived in warm sunlit seas, feeding by filtering microscopic plankton with their stinging tentacles and often forming part of reef complexes. The genus had a worldwide distribution from the Late Ordovician to Late Permian. Distribution ''Favosites'' had a vast distribution, and its fossils can be found on every continent (except Antarctica). Species The following species of ''Favosites'' have been described:''Favosites'' at |
Stromatoporoid
Stromatoporoidea is an extinct clade of sea sponges common in the fossil record from the Ordovician through the Devonian. They were especially abundant and important reef-formers in the Silurian and most of the Devonian.Stock, C.W. 2001, Stromatoporoidea, 1926–2000: ''Journal of Paleontology'', v. 75, p. 1079–1089. The group was previously thought to be related to the corals and placed in the phylum Cnidaria. They are now classified in the phylum Porifera, specifically the sclerosponges. There are numerous fossil forms with spherical, branching or encrusting skeletons of laminated calcite with vertical ''pillars'' between the ''laminae''. Specimen of its oldest genus, ''Priscastroma'', have been found within the Middle Ordovician Sediments. This same genus has been referred to as the species ''P. gemina'' Khrom., and is known to have been known to branch off into two forms, A and B. Form A gave rise to the genus ''Cystostroma'' while form B gave rise to the genus ''Labechi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentamerida
Pentamerida is an order of biconvex, impunctate shelled, articulate brachiopods that are found in marine sedimentary rocks that range from the Middle Cambrian through the Devonian.Moore, Lalcker and Fischer, 1952, Invertebrate Fossils, McGraw-Hill Pentamerids are characterized by a short hinge line where the two valves articulate, inner areas above the hinge line that slope inwardly from the beak of each valve, and a well-developed spondylium on the pedicle valve. The spondylium is a raised platform for muscle attachment found in the middle of the interior pedicle valve, generally toward the hinge and beak. The pedicle valve is the one that the pedicle, or hold-fast stalk, attaches to. The brachidia, which hold the lophophore, the ciliated feeding arms, are looped, as in the Orthida. The Short hinge line helps distinguish the pentamerids from the ancestral orthids from which they are obviously derived. The hinge line is not as short as found in the Rhynchonellida or Athyridida ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
El Paso Formation
The El Paso Formation is a geologic formation that is exposed from the Permian Basin of New Mexico and Texas to southeastern Arizona. It preserves fossils dating back to the Ordovician period. Description The formation is composed of gray cherty dolomite, limestone, and smaller amounts of siltstone. The formation often has a mottled appearance. Total thickness is . It lies unconformably on the Bliss Formation, the Coronado Sandstone, or (in the Florida Mountains) Precambrian basement, and is overlain by the Montoya Group or Portal Formation. Fossils The formation is only sparsely fossiliferous, but contains fossils of echinoderms, gastropods, trilobites, sponge spicules, and ''Nuia''. Rare ostracods, cephalopods, and brachiopods are also found, as is the trace fossil ''Planolites''. Bioherms up to high are found in the McKelligon Member, built up of siliceous sponges and receptaculitid '' Calathium''. History of investigation The formation was first named by George Burr Ri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fabric (geology)
In geology, a rock's fabric describes the spatial and geometric configuration of all the elements that make it up. In sedimentary rocks, the fabric developed depends on the depositional environment and can provide information on current directions at the time of deposition. In structural geology, fabrics may provide information on both the orientation and magnitude of the strains that have affected a particular piece of deformed rock. Types of fabric * Primary fabric — a fabric created during the original formation of the rock, e.g. a preferred orientation of clast long axes in a conglomerate, parallel to the flow direction, deposited by a fast waning current. * Shape fabric — a fabric that is defined by the preferred orientation of inequant elements within the rock, such as platy- or needle-like mineral grains. It may also be formed by the deformation of originally equant elements such as mineral grains. * Crystallographic preferred orientation — in plastically deforme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dolomitization
Dolomitization is a geological process by which the carbonate mineral dolomite is formed when magnesium ions replace calcium ions in another carbonate mineral, calcite. It is common for this mineral alteration into dolomite to take place due to evaporation of water in the sabkha area. Dolomitization involves substantial amount of recrystallization. This process is described by the stoichiometric equation: :2 CaCO3(calcite) + Mg2+ ↔ CaMg(CO3)2(dolomite) + Ca2+ Dolomitization depends on specific conditions which include low Ca:Mg ratio in solution, reactant surface area, the mineralogy of the reactant, high temperatures which represents the thermodynamic stability of the system, and the presence of kinetic inhibitors such as sulfate. If the kinetic inhibitors and high temperatures are compatible, then dolomitization can take place in saline environments above thermodynamic and kinetic saturation with respect to dolomite. This type of environment includes, freshwater and seawate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sacramento Mountains (New Mexico)
The Sacramento Mountains are a mountain range in the south-central part of the U.S. state of New Mexico, lying just east of Alamogordo in Otero County (small portions of the range lie in Lincoln County and Chaves County). From north to south, the Sacramento Mountains extend for , and from east to west they encompass .These figures are derived from the official description of the range by the Board on Geographic Names, see the for the range. Geography The Sacramentos can be divided into two sections: a main, northern section, encompassing most of the land area and all of the terrain above , and a smaller southeastern section, contiguous with the Guadalupe Mountains. Neighboring ranges and landforms include the Tularosa Basin, immediately to the west of the main section of the range; Sierra Blanca and the Capitan Mountains to the northwest and northeast; the Border Hills and the western edge of the broad Pecos River valley to the east; the Guadalupe Mountains to the southeast; ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
