Oolite or oölite (from Ancient Greek ᾠόν (ōión) 'egg stone') is a sedimentary rock formed from ooids , spherical grains composed of concentric layers. Strictly, oolites consist of ooids of diameter 0.25–2 millimetres; rocks composed of ooids larger than 2 mm are called pisolites . The term oolith can refer to oolite or individual ooids.
17-575: The Miami Rock Ridge is an oolitic , continuous outcrop of limestone , part of the Miami Formation , which formerly encompassed a large extent of southernmost South Florida ; as part of an ecosystem it formed portions of the Everglades . The traditional base of the elevation, which rises 7 to 8.6 m (23 to 28 ft) above sea level, ranges from northern Miami-Dade County —the approximate latitude of North Miami Beach —southward to
34-444: A 'seed', such as a piece of a shell. Strong intertidal currents wash the 'seeds' around on the seabed, where they accumulate layers of chemically precipitated calcite from the supersaturated water. The oolites are commonly found in large current bedding structures that resemble sand dunes. The size of the oolites reflect the time that they were exposed to the water before they were covered with later sediment. Oolites are often used in
51-545: A 6-foot-2.5-inch (1.892 m) waterfall and 450-foot-long (140 m) rapids until 1908, when it was progressively bypassed by the Miami Canal and partly dredged. Being one of the few areas sited above pre-drainage sea level, the Miami Rock Ridge was heavily exploited for agriculture and real estate . The coastal ridge was traditionally a component of the endangered pine rocklands , which grew upon
68-875: A lot of surface area, which promotes high bacterial growth. Some exemplar oolitic limestone was formed in England during the Jurassic period, and forms the Cotswold Hills , the Isle of Portland with its famous Portland Stone , and part of the North York Moors . A particular type, Bath Stone , gives the buildings of the World Heritage City of Bath their distinctive appearance. Carboniferous Hunts Bay Oolite lies under much of south Wales . The Miami Rock Ridge of southeastern Florida,
85-477: Is a common name for many species of small to medium sized ray-finned fish , normally with large heads and tapered bodies, which are found in marine, brackish and freshwater environments. Traditionally most of the species called gobies have been classified in the order Perciformes as the suborder Gobioidei but in the 5th Edition of Fishes of the World this suborder is elevated to an order Gobiiformes within
102-996: Is also found in Indiana in the United States . The town of Oolitic, Indiana , was founded for the trade in limestone and bears its name. Quarries in Oolitic, Bedford , and Bloomington contributed the materials for such U.S. landmarks as the Empire State Building in New York and the Pentagon in Arlington, Virginia . Many of the buildings on the Indiana University campus in Bloomington are built with native oolitic limestone material, and
119-674: The Soldiers' and Sailors' Monument in downtown Indianapolis , Indiana, is built mainly of grey oolitic limestone. Oolites also appear in the Conococheague limestone , of Cambrian age, in the Great Appalachian Valley in Pennsylvania , Maryland , West Virginia , and Virginia . Rogenstein is a term describing a specific type of oolite in which the cementing matter is argillaceous . Goby Goby
136-553: The clade Percomorpha . Not all the species in the Gobiiformes are referred to as gobies and the "true gobies" are placed in the family Gobiidae , while other species referred to as gobies have been placed in the Oxudercidae . Goby is also used to describe some species which are not classified within the order Gobiiformes, such as the engineer goby or convict blenny Pholidichthys leucotaenia . The word goby derives from
153-614: The Miami Rock Ridge. Today the original communities have been largely removed by development, and the remaining pieces of the ecosystems are scattered into tiny fragments in extreme southeast Florida; they now encompass small fractions of their original range. Simpson Park Hammock and Alice Wainwright Park contain small fragments of tropical hardwood hammock. Oolite Ooids are most commonly composed of calcium carbonate ( calcite or aragonite ), but can be composed of phosphate, clays, chert , dolomite or iron minerals, including hematite . Dolomitic and chert ooids are most likely
170-496: The Plain formed the bed of Lake Idaho . Wave action in the lake washed sediments back and forth in the shallows on the southwestern shore, forming ooids and depositing them on steeper benches near the shore in 2- to 40-foot thicknesses. When the lake drained (2 to 4 million years ago), the oolite was left behind, along with siltstone , volcanic tuffs and alluvium from adjacent mountain slopes. The other sediments eroded away, while
187-470: The home aquarium industry because their small grain size (0.2 to 1.22 mm) is ideal for shallow static beds and bottom covering of up to 1" in depth. Also known as "oolitic" sand, the sugar-sized round grains of this sand pass easily through the gills of gobies and other sand-sifting organisms. This unusually smooth sand promotes the growth of bacteria, which are important biofilters in home aquaria. Because of its extremely small grain size, oolitic sand has
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#1732769105463204-693: The islands of the Lower Florida Keys , and much of the Everglades , are underlain by Miami Oolite . This limestone was formed by deposition when shallow seas covered the area between periods of glaciation . The material consolidated and eroded during later exposure above the ocean surface. One of the world's largest freshwater lakebed oolites is the Shoofly Oolite, a section of the Glenns Ferry Formation on southwestern Idaho 's Snake River Plain . 10 million years ago,
221-462: The length of the ridge. The environmental community consisted of a large and continuous expanse of South Florida slash pines (Pinus elliottii var. densa) , which was interspersed by tropical hardwood hammocks . The globally imperiled pine rockland community , which also encompassed the Florida Keys and The Bahamas , supported numerous endemic plant species; 20 percent occur nowhere else in
238-517: The more resistant oolite weathered into hummocks, small arches and other natural "sculptures". The Shoofly Oolite lies on public land west of Bruneau, Idaho managed by the Bureau of Land Management (BLM). The physical and chemical properties of the Shoofly Oolite are the setting for a suite of rare plants, which the BLM protects through land use management and on-site interpretation. This type of limestone
255-399: The result of the replacement of the original texture in limestone. Oolitic hematite occurs at Red Mountain near Birmingham, Alabama , along with oolitic limestone. They are usually formed in warm, supersaturated, shallow, highly agitated marine water intertidal environments, though some are formed in inland lakes. The mechanism of formation starts with a small fragment of sediment acting as
272-546: The upper Florida Keys and extends southwestward into Everglades National Park , creating a karst -dominated landscape. A series of tidal channels, dubbed transverse glades , formed within valleys in the ridge and served as conduits for freshwater from the Everglades, thereby modulating the estuarine environment of Biscayne Bay. One of these glades enclosed the Miami River , a section of whose course featured
289-405: The world. The communities of the Miami Rock Ridge are maintained by wildfires, including natural fires caused by lightning strikes; this affects the vegetation and its associated inhabitants, thus maintaining a diverse ecosystem. The substrate—often consisting of marl —and climate also affects the height of vegetation; thus a mature subtropical hammock typically does not exceed 59 feet (18 m) on
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