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Sandbian
The Sandbian is the first stage of the Upper Ordovician. It follows the Darriwilian and is succeeded by the Katian. Its lower boundary is defined as the first appearance datum of the graptolite species '' Nemagraptus gracilis'' around million years ago. The Sandbian lasted for about 5.4 million years until the beginning of the Katian around million years ago. Naming The name Sandbian is derived from the village Södra Sandby (Lund Municipality, Skåne County, Sweden). The name was proposed in 2006. GSSP The GSSP of the Sandbian is the Fågelsång section () at Sularp Brook, east of Lund (Skåne, Sweden). It is an outcrop of shale and mudstone. The lower boundary of the Sandbian is defined as the first appearance datum of graptolite Graptolites are a group of colonial animals, members of the subclass Graptolithina within the class Pterobranchia. These filter-feeding organisms are known chiefly from fossils found from the Middle Cambrian ( Miaolingian, Wuliuan) thro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Darriwilian
The Darriwilian is the upper stage of the Middle Ordovician. It is preceded by the Dapingian and succeeded by the Upper Ordovician Sandbian Stage. The lower boundary of the Darriwilian is defined as the first appearance of the graptolite species ''Undulograptus austrodentatus'' around million years ago. It lasted for about 10.8 million years until the beginning of the Sandbian around million years ago. This stage of the Ordovician was marked by the beginning of the Andean-Saharan glaciation. Naming The name Darriwilian is derived from Darriwil, a parish in County of Grant, Victoria (Australia). The name was proposed in 1899 by Thomas Sergeant Hall. GSSP The GSSP of the Darriwilian is the Huangnitang Section () near the village Huangnitang, 3.5 km southwest of Changshan County Town (Zhejiang, China). It is an outcrop of the Ningkuo Formation, consisting of mainly black shale. The lower boundary of the Darriwilian is defined as the first appearance datum of the graptolite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sularp Brook
Sularp Brook (), Lund Municipality, Skåne, Sweden, is the location of the Global Boundary Stratotype Section and Point (GSSP) which marks the boundary between the Middle and Late epochs of the Ordovician period on the geologic time scale. The First Appearance Datum, first appearance of the graptolite ''Nemagraptus gracilis'' defines the boundary. The rock section consists primarily of dark-gray shale and mudstone, except for a phosphorus, phosphorite marker bed 1.4 m above the GSSP, and was probably Deposition (sediment), deposited at a water depth exceeding 100 m. Drill cores have revealed almost identical stratigraphy across an area several km wide. Due to heating, possibly from an Intrusion, intrusive Dike (geology), dike, the stratotype is unfit for dating by magnetic analysis, but this lack is compensated by the diversity of Chemostratigraphy, chemostratigraphic and biostratigraphy, biostratigraphic options. References * * Geology of Sweden Stratigraphy of Europe Ordo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Södra Sandby
Södra Sandby () is the second largest locality in Lund Municipality, Skåne County, Sweden with 6,136 inhabitants in 2010. It is situated about 10 kilometers east of Lund and 30 kilometers northeast of Malmö. The Sandbian Age of the Ordovician Period of geological time is named for Södra Sandby where the Lindegård Formation crops out.Södra Sandby at Fossilworks
Fossilworks was a portal which provides query, download, and analysis tools to facilitate access to the Paleobiology Database, a large relational database assembled by hundreds of paleontologists from around the world.
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Katian
The Katian is the second stage of the Upper Ordovician. It is preceded by the Sandbian and succeeded by the Hirnantian Stage. The Katian began million years ago and lasted for about 7.6 million years until the beginning of the Hirnantian million years ago. During the Katian the climate cooled which started the Late Ordovician glaciation. Naming The name Katian is derived from Katy Lake ( Atoka County, Oklahoma, United States). GSSP The GSSP of the Katian Stage is the Black Knob Ridge Section in southeastern Oklahoma (United States). It is an outcrop of the Womble Shale and the Bigfork Chert, the latter containing the lower boundary of the Katian. The lower boundary is defined as the first appearance datum of the graptolite Graptolites are a group of colonial animals, members of the subclass Graptolithina within the class Pterobranchia. These filter-feeding organisms are known chiefly from fossils found from the Middle Cambrian ( Miaolingian, Wuliuan) through t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GSSP
A Global Boundary Stratotype Section and Point (GSSP), sometimes referred to as a golden spike, is an internationally agreed upon reference point on a stratigraphic section which defines the lower boundary of a stage on the geologic time scale. The effort to define GSSPs is conducted by the International Commission on Stratigraphy, a part of the International Union of Geological Sciences. Most, but not all, GSSPs are based on paleontological changes. Hence GSSPs are usually described in terms of transitions between different faunal stages, though far more faunal stages have been described than GSSPs. The GSSP definition effort commenced in 1977. As of 2024, 79 of the 101 stages that need a GSSP have a ratified GSSP. Rules A geologic section has to fulfill a set of criteria to be adapted as a GSSP by the ICS. The following list summarizes the criteria: * A GSSP has to define the lower boundary of a geologic stage. * The lower boundary has to be defined using a primary m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graptolite
Graptolites are a group of colonial animals, members of the subclass Graptolithina within the class Pterobranchia. These filter-feeding organisms are known chiefly from fossils found from the Middle Cambrian ( Miaolingian, Wuliuan) through the Lower Carboniferous ( Mississippian). A possible early graptolite, ''Chaunograptus'', is known from the Middle Cambrian. Recent analyses have favored the idea that the living pterobranch '' Rhabdopleura'' represents an extant graptolite which diverged from the rest of the group in the Cambrian. Fossil graptolites and ''Rhabdopleura'' share a colony structure of interconnected zooids housed in organic tubes (theca) which have a basic structure of stacked half-rings (fuselli). Most extinct graptolites belong to two major orders: the bush-like sessile Dendroidea and the planktonic, free-floating Graptoloidea. These orders most likely evolved from encrusting pterobranchs similar to ''Rhabdopleura''. Due to their widespread abundance, pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mudstone
Mudstone, a type of mudrock, is a fine-grained sedimentary rock whose original constituents were clays or muds. Mudstone is distinguished from ''shale'' by its lack of fissility.Blatt, H., and R.J. Tracy, 1996, ''Petrology.'' New York, New York, W. H. Freeman, 2nd ed, 529 pp. The term ''mudstone'' is also used to describe carbonate rocks (limestone or dolomite) that are composed predominantly of carbonate mud. However, in most contexts, the term refers to siliciclastic mudstone, composed mostly of silicate minerals. The NASA Curiosity rover has found deposits of mudstone on Mars that contain organic substances such as propane, benzene and toluene. Definition There is not a single definition of mudstone that has gained general acceptance,Boggs 2006, p.143 though there is wide agreement that mudstones are fine-grained sedimentary rocks, composed mostly of silicate grains with a grain size less than . Individual grains this size are too small to be distinguished without a micros ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shale
Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of Clay mineral, clay minerals (hydrous aluminium phyllosilicates, e.g., Kaolinite, kaolin, aluminium, Al2Silicon, Si2Oxygen, O5(hydroxide, OH)4) and tiny fragments (silt-sized particles) of other minerals, especially quartz and calcite.Blatt, Harvey and Robert J. Tracy (1996) ''Petrology: Igneous, Sedimentary and Metamorphic'', 2nd ed., Freeman, pp. 281–292 Shale is characterized by its tendency to split into thin layers (Lamination (geology), laminae) less than one centimeter in thickness. This property is called ''Fissility (geology), fissility''. Shale is the most common sedimentary rock. The term ''shale'' is sometimes applied more broadly, as essentially a synonym for mudrock, rather than in the narrower sense of clay-rich fissile mudrock. Texture Shale typically exhibits varying degrees of fissility. Because of the parallel orientation of clay mineral flakes in shale, it breaks in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lund
Lund (, ;"Lund" (US) and ) is a city in the provinces of Sweden, province of Scania, southern Sweden. The town had 94,393 inhabitants out of a municipal total of 130,288 . It is the seat of Lund Municipality, Scania County. The Öresund Region, which includes ''Lund'', is home to more than 4.2 million people. Archeologists date the founding of Lund to around 990, when Scania was part of Denmark. From 1103 it was the seat of the Catholic Metropolitan Archdiocese of Lund, and the towering Lund Cathedral, built –1145, still stands at the centre of the town. Denmark ceded the city to Sweden in the Treaty of Roskilde in 1658. Lund University, established in 1666, is one of Scandinavia's oldest and largest institutions for education and research. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skåne County
Skåne County ( ), sometimes referred to as Scania County or just Scania in English, is the southernmost Counties of Sweden, county, or , of Sweden, mostly corresponding to the traditional Provinces of Sweden, province of Scania. It borders the counties of Halland County, Halland, Kronoberg County, Kronoberg and Blekinge County, Blekinge and connects to Capital Region of Denmark, Capital Region, Denmark by the Öresund Bridge across the Øresund strait. The seat of residence for the Governors of Skåne County, Skåne Governor is the city of Malmö. The headquarters of Skåne Regional Council are located in both Kristianstad and Malmö. The present county was created in 1997 when Kristianstad County and Malmöhus County were merged; it covers around 3% of Sweden's total area, while its population of 1.3 million comprises 13% of Sweden's total population. Endonym and exonym When the new county was established in 1997, it was named ''Skåne län'' as its borders coincide with tho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lund Municipality
Lund Municipality () is a municipality in Scania County, southern Sweden. Its seat is the city of Lund. As most municipalities in Sweden, the territory of municipality consists of many former local government units, united in a series of amalgamations. The number of original entities (as of 1863) is 22. At the time of the nationwide municipal reform of 1952 the number had been reduced to six. In 1967 the rural municipality ''Torn'' (itself created in 1952) was added to Lund. The ''City of Lund'' was made a unitary municipality in 1971 and amalgamated with ''Dalby'', ''Genarp'', ''Södra Sandby'' and ''Veberöd'' in 1974 completing the process. Since 2016, the municipality is subdivided into 16 districts for the purposes of population and land registration. Dalby Söderskog, one of Sweden's national parks, is located within the municipality near Dalby. The municipal bird of Lund is the Eurasian penduline tit. Localities There are nine urban areas in Lund Municipality: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
